Study Note: macOS Server Security

Initially, security was not the primary focus for the website hosting an open-source hemodynamic software package. However, the addition of a federated learning server and web-based deep learning operations has underscored the importance of implementing robust security protocols. Leveraging the capabilities of Mac Studio with its Silicon chip remains a goal to enhance the performance of custom-built, web-based deep learning algorithms. Although this system is not essential, enthusiasm for Apple products has contributed to a commitment to this investment in the future. Currently, a Linux Debian server is in use; however, to gain a thorough understanding of security protocols, an initial transition to an older Mac Mini as a macOS server has been implemented. This allows for familiarity with macOS server operations before moving to the more advanced Mac Studio setup, which is planned as the dedicated machine learning server.

The transition to macOS aims to achieve more refined control over CPU memory and network resources, ensuring efficient management and preventing overuse by any single user. This shift ultimately supports the broader objective of facilitating and accelerating advancements in clinical hemodynamic research and development.

While sharing security strategies openly might not appear advisable, the limited availability of macOS security resources makes it worthwhile to contribute insights. After extensive trial and error on the current setup, a plan is in place to document and share successful security and optimization measures, following the final server transition. This documentation is intended to assist others who may encounter similar challenges in their server setups.

Homebrew

How to Install Homebrew on macOS

Homebrew is a popular package manager for macOS that allows you to install and manage software packages easily. Here’s a step-by-step guide on how to install Homebrew and why each step is necessary.

Step 1: Install Homebrew

To begin the installation process, open the Terminal application on your Mac. Then, run the following command:

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

• /bin/bash -c: Runs the subsequent script using the Bash shell.
• curl -fsSL: Downloads the Homebrew installation script silently.
• URL: The script at this URL installs Homebrew, setting up the necessary files and directories.

Step 2: Configure Homebrew Environment

After installing Homebrew, you'll need to configure your shell environment so that you can use Homebrew commands globally on your system.

(1) Make Homebrew Configuration Persistent

Run the following command:

(echo; echo 'eval "$(/opt/homebrew/bin/brew shellenv)"') >> /Users/frank/.zprofile

• (echo; echo 'eval "$(/opt/homebrew/bin/brew shellenv)"'): This command creates the string eval "$(/opt/homebrew/bin/brew shellenv)", which is needed to set up the Homebrew environment.
• >> /Users/frank/.zprofile: Appends the string to the .zprofile file in the user's home directory (/Users/frank/). This ensures that the Homebrew environment is configured every time a new terminal session starts.

• Persistence: By adding the command to your .zprofile, the configuration persists across terminal sessions. This means you don't have to manually configure Homebrew every time you open a new terminal window.

(2) Apply Homebrew Configuration Immediately

Next, run this command to apply the configuration immediately:

eval "$(/opt/homebrew/bin/brew shellenv)"

• eval: This command evaluates and executes the command string that follows.
• $(): Runs the command inside the parentheses and returns its output.
• /opt/homebrew/bin/brew shellenv: Outputs the environment variables required by Homebrew, allowing you to use Homebrew commands right away.

• Environment Setup: This command ensures that your current shell session knows where to find Homebrew and its installed packages. It sets the necessary environment variables, such as PATH, so you can use Homebrew commands without any issues immediately after installation.

Homebrew Directory Structure

Once installed, Homebrew uses a specific directory structure to organize its files and installed packages:

• Key Directories:
  • /opt/homebrew/bin: Contains executable binaries for the installed packages. This directory is included in your PATH, allowing you to run commands without specifying the full path.
  • /opt/homebrew/Library: Contains Homebrew's core libraries and formulae that describe how to install each package.
  • /opt/homebrew/etc: Contains configuration files for installed packages.
  • /opt/homebrew/var: Stores variable data, such as databases or log files, related to installed packages.

macOS Python Environment Setup and Package Installation

(A) Check if Python is Managed by Homebrew

To determine if the Python installation on your macOS system is managed by Homebrew, follow these steps:

which python3

• If the path returned is something like /usr/local/bin/python3 (for Intel Macs) or /opt/homebrew/bin/python3 (for Apple Silicon Macs), then Python is managed by Homebrew.
• If the path is something else, such as /usr/bin/python3 or within a virtual environment like /Users/username/path/to/venv/bin/python3, then Python is not managed by Homebrew.

(B) Installing Python Packages if Python is Not Managed by Homebrew

If Python is not managed by Homebrew, you should use a virtual environment to install Python packages to avoid conflicts with the system-wide Python installation. Here’s how to do that:

Create a Virtual Environment

python3 -m venv path/to/venv

• This command creates a virtual environment in the specified directory (path/to/venv). The venv directory will contain a copy of the Python interpreter and a local installation of pip. You can replace path/to/venv with your desired directory path.
• A virtual environment is an isolated environment that includes its own Python interpreter and libraries, allowing you to manage dependencies separately for each project.

Activate the Virtual Environment

source path/to/venv/bin/activate

• The source command runs the activate script, which modifies your shell’s environment variables to point to the Python interpreter and libraries within the virtual environment.
• Activating the virtual environment ensures that all Python commands (like python3, pip, etc.) will use the Python interpreter and packages within the virtual environment.

Install Python Packages

python3 -m pip install PACKAGE_NAME

• This command installs the specified Python package (PACKAGE_NAME) into the virtual environment.
• Installing packages in the virtual environment ensures that they are only available within that environment.

python3 -m pip install flask flask_cors numpy matplotlib networkx pandas

python3 -m pip install flask==2.1.2 flask_cors==3.1.0 numpy==1.21.2 matplotlib==3.4.3 networkx==2.6.3 pandas==1.3.3

Deactivate the Virtual Environment (Optional)

deactivate

• This command restores your shell’s environment variables to their original state, effectively turning off the virtual environment.
• Deactivating the virtual environment helps prevent accidental use of the isolated environment when you’re working on other projects.

Apple Remote Desktop

Configuring a Mac for Apple Remote Desktop

To ensure smooth access and control using Apple Remote Desktop (ARD), the Mac intended for hosting must undergo specific configurations. The following guidance provides a step-by-step outline for enabling remote management, configuring permissions, and ensuring necessary network accessibility.

(A) Enable Remote Management

Access System Settings: In System Settings (or System Preferences on earlier macOS versions), navigate to General and select Sharing.

Activate Remote Management: Check the box labeled Remote Management to enable the feature on the Mac.

Specify Remote Permissions: Selecting Options within the Remote Management settings allows for detailed control over remote capabilities. Options include allowing the remote user to observe, control, generate reports, or manage files.

(B) Set Permissions for Remote Access

Define User Permissions: Within the Remote Management settings, the Options button can be used to select specific permissions, such as Observe, Control, Generate Reports, and other available controls. Selecting OK finalizes the choice of permissions.

Restrict Access to Specific Accounts: For environments where remote access must be limited to certain individuals, selecting Only these users allows for the restriction of access to specific user accounts or groups.

(C) Required Network Ports for Apple Remote Desktop

To ensure uninterrupted functionality, the following ports must be opened on network firewalls and in relevant macOS firewall configurations:

These configurations and settings collectively ensure that the Mac is accessible via Apple Remote Desktop for authorized users, enabling smooth management and screen sharing capabilities based on the permissions established.

SSH

macOS SSH Security Setup

This guide outlines the essential steps to secure SSH access on a macOS server using public key authentication.

1. Enable Remote Login on the Server

• Navigate to System Preferences > General > Sharing.
• Select Remote Login to enable SSH access.

2. Generate an SSH Key Pair on the Client

• Open Terminal and execute the following command to generate an SSH key pair:

ssh-keygen -t rsa -b 4096 -C "your_email@example.com"

• Accept the default location (~/.ssh/id_rsa) when prompted.
• Set a secure passphrase.

• Store the key pair in C:\Users\YourUsername\.ssh.
• Remove any existing SSH keys for the server:

ssh-keygen -R SERVER_ADDRESS

• Test the SSH connection:

ssh SERVER_ADDRESS

• If the username differs on the server, specify it as follows:

ssh USERID@SERVER_ADDRESS

1. Key Storage Location

   Store your SSH key pair in your user’s .ssh folder. For example, if your username is ngene, use:

   C:\Users\ngene\.ssh

2. Unzipping and Verifying Key Files
   • After unzipping your SSH key files, open a Command Prompt.
   • Navigate to the .ssh folder and run the command below to display all files, including hidden ones:

     dir /a

   • This step confirms that all key files have been extracted correctly.
3. Copying Key Files

   If you encounter issues copying the files via the command line (for example, using copy .ssh C:\Users\ngene\. didn't work), use Windows Explorer to manually copy the four key files into the folder:

   C:\Users\ngene\.ssh

4. Cleaning Up Old Keys

   Before connecting, remove any existing SSH keys for the server to avoid conflicts:

   ssh-keygen -R SERVER_ADDRESS

   Replace SERVER_ADDRESS with your server’s address.

5. Testing the SSH Connection
   • Default Username:

     Test the connection using:

     ssh SERVER_ADDRESS

   • Different Username:

     If your server username differs from your local one, specify it like so:

     ssh USERID@SERVER_ADDRESS

     Replace USERID with the appropriate username for the server.

3. Copy the Public Key to the Server

• Transfer the public key to the server:

ssh-copy-id SPECIFIC_ID@SERVER_ADDRESS

• Replace SPECIFIC_ID with the appropriate username.
• Replace SERVER_ADDRESS with the server's address.

4. Configure SSH on the Server

• Open the SSH configuration file with a text editor:

sudo emacs /etc/ssh/sshd_config

• Update the following settings:

PermitRootLogin no
AllowUsers SPECIFIC_ID
AuthorizedKeysFile .ssh/authorized_keys
PasswordAuthentication no
ChallengeResponseAuthentication no
PermitEmptyPasswords no
UsePAM no

• Ensure that SPECIFIC_ID is replaced with the desired username.

5. Restart the SSH Service

• Apply the changes by rebooting the system:

sudo shutdown -r now

ssh -p 2222 ID@SERVER

ssh -i ~/.ssh/id_rsa ID@SERVER

ssh -v ID@SERVER

nginx

macOS nginx Security Setup

# /opt/homebrew/etc/nginx/nginx.conf

# Run worker processes as a non-privileged user for security
user nobody;

# Define the number of worker processes based on CPU cores
worker_processes auto;

# Events block configuration
events {
      worker_connections 1024; # Maximum number of simultaneous connections per worker
}

# Main HTTP block
http {
      # Log file paths for error and access logs
      error_log /opt/homebrew/etc/nginx/error.log;
      access_log /opt/homebrew/etc/nginx/access.log;
      # access_log /opt/homebrew/etc/nginx/access.log main;
      

      # Security headers to protect against common web vulnerabilities
      add_header X-Content-Type-Options nosniff;
      add_header X-Frame-Options SAMEORIGIN;
      add_header X-XSS-Protection "1; mode=block";
      add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;

      # Hide Nginx version to prevent targeted attacks based on known vulnerabilities
      server_tokens off;

      # Limit the maximum allowed size of client requests
      client_max_body_size 10M;

      # Rate limiting zone definition to control traffic and protect against DoS attacks
      # Define a rate limiting zone with a rate of 1 request per second
      # limit_req_zone $binary_remote_addr zone=one:10m rate=1r/s;

      # Define a rate limiting zone with an increased rate of 20 requests per second
      limit_req_zone $binary_remote_addr zone=one:10m rate=20r/s;

      # HTTP Server Block
      server {
           listen 80;
           server_name localhost;

           # Deny access to sensitive locations
           location /secret {
                deny all;
           }

           # Main location configuration with rate limiting
           location / {
                root   html;
                index  index.html;

                # Apply rate limiting to this location
                limit_req zone=one burst=10 nodelay;
           }

           # Error page for server errors
           error_page 500 502 503 504 /50x.html;
           location = /50x.html {
                root html;
           }
      }

      # HTTPS Server Block
      server {
           listen 443 ssl;
           server_name www.ngene.org;

           # SSL/TLS settings for secure HTTPS connections
           ssl_certificate      /opt/homebrew/etc/nginx/ssl/ngene.crt;
           ssl_certificate_key  /opt/homebrew/etc/nginx/ssl/ngene.key;
           ssl_session_cache    shared:SSL:1m;
           ssl_session_timeout  5m;
           ssl_ciphers  HIGH:!aNULL:!MD5;
           ssl_prefer_server_ciphers  on;

           # Deny access to sensitive locations
           location /secret {
                deny all;
           }

           # Main location with enhanced security settings
           location / {
                root   html;
                index  index.html;

                # Rate limiting configuration
                limit_req zone=one burst=10 nodelay;
           }
      }
}

Detailed Explanation of Key Directives

user nobody;

worker_processes auto;
events {
	worker_connections 1024;
}

error_log /opt/homebrew/etc/nginx/error.log;
access_log /opt/homebrew/etc/nginx/access.log main;

add_header X-Content-Type-Options nosniff;
add_header X-Frame-Options SAMEORIGIN;
add_header X-XSS-Protection "1; mode=block";
add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;

server_tokens off;

client_max_body_size 10M;

# Define a rate limiting zone with a rate of 1 request per second
# limit_req_zone $binary_remote_addr zone=one:10m rate=1r/s;

# Define a rate limiting zone with an increased rate of 20 requests per second
limit_req_zone $binary_remote_addr zone=one:10m rate=20r/s;

limit_req zone=one burst=5;

server {
	listen 80;
	server_name localhost;

	# Deny access to sensitive locations
	location /secret {
	      deny all;
	}

	# Main location configuration with rate limiting
	location / {
	      root   html;
	      index  index.html;

	      # Apply rate limiting to this location
              limit_req zone=one burst=10 nodelay;
	}

	# Error page for server errors
	error_page 500 502 503 504 /50x.html;
	location = /50x.html {
	      root html;
	}
}

server {
	listen 443 ssl;
	server_name www.ngene.org;

	# SSL/TLS settings for secure HTTPS connections
	ssl_certificate      /opt/homebrew/etc/nginx/ssl/ngene.crt;
	ssl_certificate_key  /opt/homebrew/etc/nginx/ssl/ngene.key;
	ssl_session_cache    shared:SSL:1m;
	ssl_session_timeout  5m;
	ssl_ciphers  HIGH:!aNULL:!MD5;
	ssl_prefer_server_ciphers  on;

	# Deny access to sensitive locations
	location /secret {
	     deny all;
	}

	# Main location with enhanced security settings
	location / {
	     root   html;
	     index  index.html;

	     # Rate limiting configuration
	     limit_req zone=one burst=10 nodelay;
	}
}

Steps to Follow After Modifying nginx.conf

After you've made changes to your Nginx configuration file (nginx.conf), you'll need to verify, restart, and monitor your Nginx server to ensure everything is working correctly. Here’s how to do it:

Step 1: Test the Nginx Configuration

This command checks the syntax of your nginx.conf file to ensure there are no errors. It is a safe way to confirm that your changes are correctly formatted and won't cause Nginx to crash.

sudo nginx -t

Step 2: Restart the Nginx Service

This command restarts the Nginx server using Homebrew's service management tool. It applies the changes you've made in the nginx.conf file and restarts the service to ensure those changes take effect.

sudo brew services restart nginx

Step 3: Monitor Access and Error Logs

These commands allow you to view real-time updates to the Nginx access and error logs. This monitoring helps you track server activity and quickly identify issues that may arise after changes.

tail -f /opt/homebrew/etc/nginx/access.log

tail -f /opt/homebrew/etc/nginx/error.log

• Access Log (tail -f /opt/homebrew/etc/nginx/access.log): Displays incoming requests to your server, including IP addresses, request types, response statuses, and more. It's useful for understanding traffic patterns and user interactions with your site.
• Error Log (tail -f /opt/homebrew/etc/nginx/error.log): Shows error messages and warnings generated by the server. It helps in diagnosing problems, such as configuration errors or server crashes, that might occur after applying changes.

Step 4: Verify the Website's Response

This command sends a request to your website to retrieve the HTTP headers. It's a quick way to verify that your site is accessible and that the server is responding correctly after the restart.

curl -I https://ngene.org

Verifying the HTTP response ensures that your site is reachable and that the server is functioning as expected. If the response includes a status code like 200 OK, it means the server is correctly handling requests. If you receive errors like 404 Not Found or 500 Internal Server Error, it indicates issues that need addressing.

Setting Up Log Rotation for nginx Logs Using logrotate

This guide provides comprehensive instructions to configure log rotation for Nginx logs on macOS using logrotate. The process includes adjusting the system's PATH, creating necessary configuration files, testing the setup, and scheduling regular rotations to ensure efficient log management.

(A) Adjusting the System PATH

After installing logrotate via Homebrew, it may be observed that logrotate is not placed in the typical Homebrew installation paths (/usr/local/bin or /opt/homebrew/bin on Apple Silicon Macs). Instead, it is located in /usr/local/sbin. To make logrotate accessible from the command line, the system's PATH environment variable needs to include this directory.

1. Determine the Installation Path

   Use the whereis command to locate logrotate:

   whereis logrotate
   

   The output should indicate the path as /usr/local/sbin/logrotate.

2. Update the PATH Environment Variable

   Edit the shell profile to include /usr/local/sbin by using emacs to modify the .zprofile file:

   emacs ~/.zprofile
   

   Add the following line to the file:

   export PATH="/usr/local/sbin:$PATH"
   

   Save and exit the editor.

3. Reload the Shell Profile

   Apply the changes by sourcing the profile:

   source ~/.zprofile
   

(B) Creating Logrotate Configuration for Nginx

B-1) Creating Configuration Directories and Files

To set up logrotate after installation:

1. Create the Configuration Directory

   Use the mkdir command with the -p option to create the necessary directories, including any parent directories that do not exist:

   sudo mkdir -p /usr/local/etc/    

   Explanation: The -p option stands for "parents" and allows the creation of nested directories without error if they already exist.

2. Create the Main Configuration File

   Create and edit the main configuration file using emacs:

   sudo emacs /usr/local/etc/logrotate.conf    

3. Define the Main Configuration

   In logrotate.conf, include the following line to incorporate configurations from the logrotate.d directory:

   # Example main configuration file for logrotate
   include /usr/local/etc/logrotate.d    

4. Create an Additional Directory for Modular Configurations

   (Optional but recommended for organized configurations):

   sudo mkdir -p /usr/local/etc/logrotate.d    

5. Create the Nginx Logrotate Configuration File

   ```bash sudo emacs /usr/local/etc/logrotate.d/nginx.conf ```

B-2) Configuring Log Rotation for Nginx Logs

Add the following configuration to nginx.conf:

sudo emacs /usr/local/etc/logrotate.d/nginx.conf

/opt/homebrew/etc/nginx/*.log {
    daily
    rotate 7
    compress
    delaycompress
    missingok
    notifempty
    create 644 root wheel
    sharedscripts
    postrotate
    /usr/local/bin/nginx -s reopen
    endscript
}

• /opt/homebrew/etc/nginx/*.log: Specifies the log files to rotate.
• daily: Rotate logs daily.
• rotate 7: Keep seven rotated logs.
• compress: Compress rotated logs to save disk space.
• delaycompress: Delay compression until the next rotation cycle.
• missingok: Do not issue an error if the log file is missing.
• notifempty: Do not rotate empty log files.
• create 644 root wheel: Create new log files with specified permissions and ownership.
• sharedscripts: Run post-rotation scripts only once, not per log file.
• postrotate / endscript: Commands to execute after rotation, such as reopening Nginx logs.

Note: Adjust the path to the Nginx executable (/usr/local/bin/nginx or /opt/homebrew/bin/nginx) if it is installed in a different location.

B-3) Example Configurations for Various Scenarios

/opt/homebrew/etc/nginx/*.log {
    weekly
    rotate 4
    compress
    delaycompress
    missingok
    notifempty
    create 644 root wheel
    sharedscripts
    postrotate
    /usr/local/bin/nginx -s reopen
    endscript
}

• weekly: Rotate logs on a weekly basis.
• rotate 4: Retain four weeks of rotated logs.
• Other directives remain as previously explained.

This configuration rotates the logs weekly and retains logs for four weeks.

/opt/homebrew/etc/nginx/*.log {
    size 100M
    rotate 0
    compress
    delaycompress
    missingok
    notifempty
    create 644 root wheel
    sharedscripts
    postrotate
    /usr/local/bin/nginx -s reopen
    endscript
}

• size 100M: Rotate logs when they reach 100 megabytes in size.
• rotate 0: Do not limit the number of rotated logs; retain all rotated logs.
• Other directives remain as previously explained.

This configuration rotates the logs when they reach 100MB and does not limit the number of rotated logs.

/opt/homebrew/etc/nginx/*.log {
    monthly
    rotate 12
    compress
    delaycompress
    missingok
    notifempty
    create 644 root wheel
    sharedscripts
    postrotate
    /usr/local/bin/nginx -s reopen
    endscript
}

• monthly: Rotate logs on a monthly basis.
• rotate 12: Retain twelve months of rotated logs.
• Other directives remain as previously explained.

This configuration rotates the logs monthly and retains logs for twelve months.

Note: Adjust the path to the Nginx executable (/usr/local/bin/nginx or /opt/homebrew/bin/nginx) if it is installed in a different location.

(C) Testing the Logrotate Configuration

1. Run Logrotate in Debug Mode

   Use the -d flag to check the configuration without making any changes:

   sudo logrotate -d /usr/local/etc/logrotate.conf    

   Note: The debug mode prints messages to verify that the configuration is read correctly and shows what actions would be taken.

2. Force a Log Rotation

   If the configuration is correct, force a log rotation:

   sudo logrotate -f /usr/local/etc/logrotate.conf    

   Explanation: The -f flag forces logrotate to rotate the logs regardless of whether it thinks it needs to.

3. Verify Log Rotation

   List the contents of the Nginx log directory to confirm that logs have been rotated:

   ls -lh /opt/homebrew/etc/nginx/    

   Rotated log files such as access.log.1.gz and error.log.1.gz should be present.

(D) Scheduling Logrotate to Run Periodically

Scheduling logrotate to run automatically is essential to ensure that log files are rotated regularly without manual intervention. Regular log rotation prevents log files from consuming excessive disk space, maintains system performance, and ensures that log data is organized and manageable.

Understanding Logrotate's Operation

1. Logrotate as a Non-Daemon Process

   Logrotate does not run continuously in the background as a daemon. Instead, it operates as a command-line tool that performs log rotation tasks when invoked. This design means that logrotate relies on external mechanisms to trigger its execution at desired intervals.

2. Execution Mechanism

   When logrotate is executed, it reads its configuration files to determine which log files to process and how to handle them (e.g., rotation frequency, compression, retention). After performing the necessary actions, logrotate exits until it is called again.

Necessity of Scheduling Logrotate

1. Automatic Invocation

   To achieve automatic and regular log rotation, logrotate must be scheduled to run periodically. Without scheduling, logrotate will not perform any log rotation tasks unless it is manually executed each time.

2. Role of Scheduling Tools

   Scheduling tools like cron (or launchd on macOS) are responsible for invoking logrotate at specified intervals. These tools ensure that logrotate runs consistently without manual intervention, adhering to the rotation policies defined in its configuration files.

Why Scheduling is Essential

• Consistency: Ensures that log rotation occurs regularly (e.g., daily, weekly), preventing log files from growing indefinitely.
• Automation: Eliminates the need for manual execution, reducing the risk of human error and oversight.
• System Performance: Helps maintain optimal system performance by managing disk space consumed by log files.
• Compliance and Maintenance: Facilitates compliance with data retention policies and simplifies log management.

Implementing Scheduling with Cron

Given that logrotate does not operate as a daemon, setting up a scheduled task is crucial. Below is a concise overview of how to schedule logrotate using cron on macOS:

1. Edit the Crontab

   Open the crontab editor:

   EDITOR=emacs crontab -e    

2. Add a Daily Cron Job

   Insert the following line to schedule logrotate to run daily at midnight:

   0 0 * * * /usr/local/sbin/logrotate /usr/local/etc/logrotate.conf    

   Explanation of the Cron Schedule:

   • 0 0 * * *: Specifies that the job runs daily at 00:00 (midnight).
   • /usr/local/sbin/logrotate /usr/local/etc/logrotate.conf: Command to execute logrotate with the specified configuration file.
3. Save and Exit

   After adding the cron job, save the changes and exit the editor. The cron daemon will now handle the periodic execution of logrotate based on the defined schedule.

fail2ban

Configuring fail2ban on macOS Silicon

fail2ban is a crucial security tool that helps protect your server from various types of brute force and malicious attacks by monitoring log files and banning IPs that show suspicious behavior.

fail2ban is an intrusion prevention software framework that protects computer servers from brute-force attacks. It works by scanning log files and banning IPs that exhibit malicious behaviors, such as too many password failures, seeking for exploits, etc.

Installation and Basic Setup

Installation Steps

1. Install fail2ban using Homebrew:

brew install fail2ban

2. Directory Structure:

• Configuration files typically reside in /usr/local/etc/fail2ban/
• Logs can be found at /usr/local/var/log/fail2ban.log

Configuration

(A) Copy the Default Configuration File

Create a local copy of the default configuration file.

sudo cp /usr/local/etc/fail2ban/jail.conf /usr/local/etc/fail2ban/jail.local

(B) SSH

Open the jail.local file and enable the SSH jail by adding or modifying the following section:

[sshd]
      enabled = true
      port = ssh
      filter = sshd
      logpath = /var/log/auth.log
      maxretry = 5

(C) nginx

[Choice 1 of 2] Separated Configuration

You can add separate sections for monitoring authentication errors and access logs if they are for different types of issues or combine them if you want a unified approach. Here's an example configuration that includes both log files:

    [nginx-http-auth]
    enabled = true
    port = http,https
    filter = nginx-http-auth
    logpath = /opt/homebrew/etc/nginx/error.log
    maxretry = 3
    bantime = 3600

    [nginx-access]
    enabled = true
    port = http,https
    filter = nginx-access
    logpath = /opt/homebrew/etc/nginx/access.log
    maxretry = 5
    bantime = 3600
  

Filter Definitions

nginx-http-auth Filter:
Create or edit the filter file /opt/homebrew/etc/fail2ban/filter.d/nginx-http-auth.conf to match patterns related to authentication issues.

Example filter configuration for nginx-http-auth:

    [Definition]
    failregex = ^<HOST> - .* "GET .* HTTP/.*" 401 .*
    ignoreregex =
  

nginx-access Filter:
Create or edit the filter file /opt/homebrew/etc/fail2ban/filter.d/nginx-access.conf to match patterns related to access issues.

Example filter configuration for nginx-access:

    [Definition]
    failregex = ^<HOST> - .* "GET .* HTTP/.*" 404 .*
    ignoreregex =
  

[Choice 2 of 2] Combined Configuration

If you prefer to combine the monitoring of both logs under a single section, you can specify multiple log paths in the logpath directive. Here’s an example:

    [nginx]
    enabled = true
    port = http,https
    filter = nginx
    logpath = /opt/homebrew/etc/nginx/error.log /opt/homebrew/etc/nginx/access.log
    maxretry = 5
    bantime = 3600
  

Combined Filter Definition

Create or edit the filter file /opt/homebrew/etc/fail2ban/filter.d/nginx.conf to include patterns from both error.log and access.log.

Example combined filter configuration for nginx:

    [Definition]
    failregex = ^<HOST> - .* "GET .* HTTP/.*" 401 .*  # Unauthorized access
    ^<HOST> - .* "GET .* HTTP/.*" 404 .*  # Not found
    ignoreregex =
  

Advanced Configuration

Persistent Bans

To make bans persistent across reboots, add the following:

[DEFAULT]
      bantime = -1

Ensure bans persist across reboots by using a database.

dbfile = /var/lib/fail2ban/fail2ban.sqlite3

Whitelist Trusted IPs

To whitelist certain IPs, add:

ignoreip = 127.0.0.1/8 ::1 192.168.1.0/24

Avoid banning trusted IPs.

ignoreip = 127.0.0.1/8 ::1 192.168.1.0/24

Integration with Firewalls

Integrate fail2ban with your firewall, e.g., pf on macOS:

[DEFAULT]
      banaction = pf

Integrate fail2ban with firewalls like iptables or pf to enhance security:

[DEFAULT]
      banaction = iptables-multiport

(A) Core Components

A-1) Jails

Definition: A jail specifies the combination of a filter and an action.

Configuration: Jails are defined in the configuration file (/usr/local/etc/fail2ban/jail.conf or /usr/local/etc/fail2ban/jail.local).

Example:

[sshd]
      enabled = true
      port = ssh
      filter = sshd
      logpath = /var/log/auth.log
      maxretry = 5
      bantime = 3600

A-2) Filters

Definition: Filters define the patterns to search for in log files.

Location: Filters are stored in the /usr/local/etc/fail2ban/filter.d/ directory.

Example:

[Definition]
      failregex = ^<HOST> - .* "GET .* HTTP/.*" 404 .*
      ignoreregex =

Custom Filters:

Create custom filters by defining regex patterns:

Custom filter file: /usr/local/etc/fail2ban/filter.d/custom.conf

[Definition]
      failregex = <custom-regex-pattern>

Create custom filters for unique log patterns. Create a file in /etc/fail2ban/filter.d/custom.conf:

[Definition]
      failregex = <CUSTOM_REGEX>
      ignoreregex =

A-3) Actions

Definition: Actions define what to do when a filter catches an event.

Common Actions: Banning an IP via iptables, sending email notifications, etc.

Example:

action = iptables[name=HTTP, port=http, protocol=tcp]

Custom Actions:

Create custom actions to integrate with other security tools or logging systems.

action = %(action_mwl)s

Define custom actions in /usr/local/etc/fail2ban/action.d/:

Create custom.conf:

[Definition]
      actionstart = <custom-start-command>
      actionstop = <custom-stop-command>
      actioncheck = <custom-check-command>

(B) SSH

B-1) Rate-Limiting and SSH Specifics

Invalid User Attempts:

[sshd-invalid]
      enabled = true
      logpath = /var/log/auth.log
      filter = sshd-invalid
      maxretry = 3

Non-standard Port:

[sshd]
      port = 2222

Brute-force Detection:

[sshd]
      enabled = true
      logpath = /var/log/auth.log
      maxretry = 5

B-2) Custom Patterns for SSH

SSH Invalid User Attempts

[ssh-invalid-user]
      enabled = true
      filter = sshd-invalid-user
      logpath = /var/log/auth.log
      maxretry = 3
      bantime = 3600

      [Definition]
      failregex = ^<HOST> .* Invalid user .*$

      ignoreregex =

SSH Connection Attempts with Non-Standard Port

[ssh-non-standard-port]
      enabled = true
      filter = sshd-non-standard-port
      logpath = /var/log/auth.log
      maxretry = 3
      bantime = 3600

      [Definition]
      failregex = ^<HOST> .* Failed password for .* from <HOST> port [^22].*$

      ignoreregex =

SSH Brute-Force Detection

[ssh-brute-force]
      enabled = true
      filter = sshd-brute-force
      logpath = /var/log/auth.log
      maxretry = 5
      bantime = 3600

      [Definition]
      failregex = ^<HOST> .* Received disconnect from <HOST>: 3: .* Too many authentication failures for .*$

      ignoreregex =

Implement rate limiting to mitigate abuse

[http-get-dos]
      enabled = true
      port = http,https
      filter = http-get-dos
      logpath = /var/log/nginx/access.log
      maxretry = 300
      findtime = 300
      bantime = 600

      action = iptables[name=HTTP, port=http, protocol=tcp]

(C) nginx

C-1) NGINX Specifics

404 Error Pattern:

[nginx-404]
      enabled = true
      logpath = /opt/homebrew/etc/nginx/access.log
      maxretry = 10

Multiple Failed Login Attempts:

[nginx-login]
      enabled = true
      logpath = /opt/homebrew/etc/nginx/error.log
      maxretry = 3

SQL Injection Attempts:

[nginx-sqli]
      enabled = true
      logpath = /opt/homebrew/etc/nginx/error.log
      maxretry = 1
      filter = nginx-sqli

C-2) Custom Patterns for NGINX

NGINX 404 Error Pattern

[nginx-404-errors]
      enabled = true
      filter = nginx-404
      logpath = /opt/homebrew/etc/nginx/access.log
      maxretry = 10
      bantime = 3600

      [Definition]
      failregex = ^<HOST> - .* "GET .* HTTP/.*" 404 .*$

      ignoreregex =

NGINX Multiple Failed Login Attempts

[nginx-login-fail]
      enabled = true
      filter = nginx-login-fail
      logpath = /opt/homebrew/etc/nginx/error.log
      maxretry = 5
      bantime = 3600

      [Definition]
      failregex = ^<HOST> - .* "POST /login.*" 401 .*$

      ignoreregex =

NGINX SQL Injection Attempts

[nginx-sql-injection]
      enabled = true
      filter = nginx-sql-injection
      logpath = /opt/homebrew/etc/nginx/access.log
      maxretry = 1
      bantime = 86400

      [Definition]
      failregex = ^<HOST> - .* "GET .*select.*from.* HTTP/.*" 403 .*$

      ignoreregex =

(D) Granular Ban

D-1) Granular Ban Settings

Define ban times and retry limits:

[DEFAULT]
      bantime = 1h
      findtime = 10m
      maxretry = 3

D-2) Granular Ban Settings'

Ban Time: Duration for which an IP is banned.

bantime = 3600  # 1 hour

Find Time: Time window within which maxretry attempts are counted.

findtime = 600  # 10 minutes

Max Retry: Number of attempts allowed before banning.

maxretry = 5

Starting and Managing fail2ban

(A) Start fail2ban

sudo fail2ban-client start

Enable fail2ban at Startup

To ensure fail2ban starts at boot, create a LaunchDaemon. Save the following as /Library/LaunchDaemons/com.fail2ban.plist:

<?xml version="1.0" encoding="UTF-8"?>
      <!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
      <plist version="1.0">
      <dict>
      <key>Label</key>
      <string>com.fail2ban</string>
      <key>ProgramArguments</key>
      <array>
      <string>/usr/local/bin/fail2ban-client</string>
      <string>start</string>
      </array>
      <key>RunAtLoad</key>
      <true/>
      <key>KeepAlive</key>
      <true/>
      </dict>
      </plist>

Load the Daemon

sudo launchctl load /Library/LaunchDaemons/com.fail2ban.plist

(B) Monitoring and Logs

Check fail2ban Status

sudo fail2ban-client status

Check Specific Jail Status

sudo fail2ban-client status sshd
      sudo fail2ban-client status nginx-http-auth

Unban an IP

sudo fail2ban-client set sshd unbanip <IP_ADDRESS>

View Logs

Check fail2ban logs:

tail -f /usr/local/var/log/fail2ban.log

Restart fail2ban

sudo brew services restart fail2ban

Web Security

DevTools Detection: Methods, Challenges, and Solutions for Securing Client-Side Interactions

(A) Detection Methods

A-1) Detecting DevTools via Window Dimensions

When DevTools are activated, especially when docked to the side or bottom of the browser window, they occupy a portion of the viewport. By continuously monitoring the discrepancy between window.outerWidth and window.innerWidth (as well as their height counterparts), it becomes feasible to infer the presence of DevTools based on significant differences in these dimensions.

(function() {
	  const threshold = 160; // Approximate width or height of DevTools pane
	  let devtoolsOpen = false;

	  const detectDevTools = () => {
	  const widthDifference = window.outerWidth - window.innerWidth;
	  const heightDifference = window.outerHeight - window.innerHeight;

	  if (widthDifference > threshold || heightDifference > threshold) {
          if (!devtoolsOpen) {
          devtoolsOpen = true;
          alert("Developer tools detected! Access is restricted.");
          }
	  } else {
          devtoolsOpen = false;
	  }
	  };

	  window.addEventListener('resize', detectDevTools);
	  detectDevTools();
	  setInterval(detectDevTools, 1000);
	  })();  

Why It's Popular

• Simplicity: The method is straightforward to implement, requiring minimal code without complex logic.
• Non-Intrusiveness: Monitoring window dimensions does not directly interfere with user interactions unless DevTools are detected.
• Cross-Browser Compatibility: This approach functions reasonably well across major browsers such as Chrome, Firefox, and Edge.

Caveats

• False Positives: Users resizing their browser window or utilizing devices with varying screen sizes may inadvertently trigger detections.
• DevTools Positioning: If DevTools are undocked into a separate window, this method may fail to detect them since the main browser window's dimensions remain unchanged.
• Evasion Techniques: Advanced users can employ scripts or browser extensions to mask dimension changes, rendering this detection ineffective.

(function() {
	    let devtoolsOpen = false;
	    const threshold = 160; // Adjust based on testing

	    const detectDevTools = () => {
	    const start = performance.now();
	    debugger; // Triggers DevTools to pause
	    const end = performance.now();

	    if (end - start > threshold) {
            devtoolsOpen = true;
            alert("Developer tools detected! Access is restricted.");
	    }
	    };

	    // Periodically check for DevTools
	    setInterval(detectDevTools, 1000);
	    })();  

(function() {
	    let devtoolsOpen = false;

	    const element = new Image();
	    Object.defineProperty(element, 'id', {
	    get: function() {
	    devtoolsOpen = true;
	    alert("Developer tools detected! Access is restricted.");
	    }
	    });

	    console.log(element);
	    })();  

(function() {
	    const element = new Image();
	    Object.defineProperty(element, 'id', {
	    get: function() {

	    // DevTools opened
	    alert("Developer tools detected! Access is restricted.");
	    }
	    });

	    // Trigger the getter by logging the element
	    console.log(element);
	    })();  

(function() {
	    let devtoolsOpen = false;
	    const threshold = 160;

	    const checkDevTools = () => {
	    const start = performance.now();
	    debugger;
	    const end = performance.now();

	    if (end - start > threshold) {
            devtoolsOpen = true;
            alert("Developer tools detected! Access is restricted.");
	    }
	    };

	    setInterval(checkDevTools, 1000);
	    })();  

(B) Combining Multiple Techniques for Enhanced Detection

(function() {
	  const threshold = 160;
	  let devtoolsOpen = false;

	  const detectByDimensions = () => {
	  const widthDifference = window.outerWidth - window.innerWidth;
	  const heightDifference = window.outerHeight - window.innerHeight;
	  return widthDifference > threshold || heightDifference > threshold;
	  };

	  const detectByTiming = () => {
	  const start = performance.now();
	  debugger;
	  const end = performance.now();
	  return end - start > threshold;
	  };

	  const detectDevTools = () => {
	  if (detectByDimensions() || detectByTiming()) {
          if (!devtoolsOpen) {
          devtoolsOpen = true;
          alert("Developer tools detected! Access is restricted.");
          }
	  } else {
          devtoolsOpen = false;
	  }
	  };

	  window.addEventListener('resize', detectDevTools);
	  detectDevTools();
	  setInterval(detectDevTools, 1000);
	  })();  

• Increased Complexity: Combining methods elevates the complexity of the detection script, potentially introducing new vulnerabilities or unintended behaviors.
• User Experience Impact: Enhanced detection mechanisms may further disrupt the user experience, particularly if multiple detections are triggered simultaneously.

(C) Responding to Detected DevTools Usage

C-1) Redirecting to an "Access Denied" Page

Instead of attempting to close the browser window, redirecting the user to a dedicated "Access Denied" page provides a controlled and informative response to detected DevTools usage.

(function() {
	const threshold = 160; // Approximate width or height of DevTools pane
	let devtoolsOpen = false;

	const detectDevTools = () => {
	const widthDifference = window.outerWidth - window.innerWidth;
	const heightDifference = window.outerHeight - window.innerHeight;

	if (widthDifference > threshold || heightDifference > threshold) {
        if (!devtoolsOpen) {
        devtoolsOpen = true;
	alert("Developer tools detected! Access is restricted.");
	window.location.href = "https://yourdomain.com/access-denied.html";
        }
	} else {
        devtoolsOpen = false;
	}
	};
	
	window.addEventListener('resize', detectDevTools);
	detectDevTools();
	setInterval(detectDevTools, 1000);
	})();  

Advantages:

• User-Friendly: Provides a clear and controlled message without forcibly disrupting the browser session.
• Guidance: Directs users to a specific page where further explanations or instructions can be provided.

Considerations:

• User Experience: Ensure that legitimate users, such as developers or accessibility testers, are not inadvertently redirected.
• Bypass Potential: Users with advanced knowledge may find ways to circumvent client-side detections, rendering redirection ineffective.

C-2) Displaying an Overlay or Modal Message

Implementing an overlay or modal can effectively block interaction with the underlying content, conveying a message to the user without redirecting them to another page.

(function() {
	const threshold = 160;
	let devtoolsOpen = false;

	const detectDevTools = () => {
	const widthDifference = window.outerWidth - window.innerWidth;
	const heightDifference = window.outerHeight - window.innerHeight;

	if (widthDifference > threshold || heightDifference > threshold) {
        if (!devtoolsOpen) {
        devtoolsOpen = true;
        document.getElementById('devtools-overlay').style.display = 'flex';
        }
	} else {
        if (devtoolsOpen) {
        devtoolsOpen = false;
        document.getElementById('devtools-overlay').style.display = 'none';
        }
	}
	};

	window.addEventListener('resize', detectDevTools);
	detectDevTools();
	setInterval(detectDevTools, 1000);
	})();  

Advantages:

• Immediate Feedback: Users receive instant notification without leaving the current page.
• Customization: The overlay can be styled to align with the website's design and messaging requirements.

Considerations:

• Accessibility: Ensure that the overlay is accessible to all users, including those utilizing assistive technologies.
• False Positives: Users resizing their windows or employing multiple monitors may unintentionally trigger the overlay.

C-3) Informing Users Without Blocking Access

In certain scenarios, informing users about DevTools usage without restricting their access can maintain a positive user experience while conveying important messages.

(function() {
	const threshold = 160;
	let devtoolsOpen = false;

	const notifyDevTools = () => {
	const widthDifference = window.outerWidth - window.innerWidth;
	const heightDifference = window.outerHeight - window.innerHeight;

	if (widthDifference > threshold || heightDifference > threshold) {
        if (!devtoolsOpen) {
        devtoolsOpen = true;
        console.warn("Developer tools detected.");
        showNotification();
        }
	} else {
        devtoolsOpen = false;
	}
	};

	   const showNotification = () => {
	  const notification = document.createElement('div');
	  notification.id = 'devtools-notification';
	  notification.style.position = 'fixed';
	  notification.style.bottom = '20px';
	  notification.style.right = '20px';
	  notification.style.padding = '10px 20px';
	  notification.style.backgroundColor = '#333';
	  notification.style.color = '#fff';
	  notification.style.borderRadius = '5px';
	  notification.style.boxShadow = '0 0 10px rgba(0,0,0,0.5)';
	  notification.innerText = 'Developer tools detected. Please refrain from inspecting the site.';
	  document.body.appendChild(notification);

	  setTimeout(() => {
          if (document.getElementById('devtools-notification')) {
          document.getElementById('devtools-notification').remove();
          }
	  }, 5000);
	  };

	window.addEventListener('resize', notifyDevTools);
	notifyDevTools();
	setInterval(notifyDevTools, 1000);
	})();  

Advantages:

• Non-Intrusive: Users are informed without being blocked or redirected, preserving access.
• User-Friendly: Maintains a positive user experience while still conveying important messages.

Considerations:

• Visibility: Ensure that notifications are noticeable without being disruptive.
• Customization: Tailor the notification's appearance and messaging to align with the website's tone and purpose.

Restricting Access to Webpages

Below is a structured comparison of commonly employed approaches for allowing only authorized users to view specific webpages. The methods are arranged from easiest to most complex, with a focus on highlighting security implications, scalability, and setup requirements.

Written on December 16th, 2024

Client-Side Scripts in JavaScript

Client-side scripts rely on the browser’s capability to execute JavaScript to determine whether access should be granted. This approach is inherently limited and insecure, as the underlying logic can be inspected and bypassed by individuals with basic knowledge of browser developer tools. Nevertheless, client-side restriction can serve as a lightweight gating mechanism for non-sensitive content or for demonstration purposes.

1. The Basic Concept

Client-side scripts typically utilize JavaScript functions that evaluate certain conditions, such as a password prompt or a localStorage token, before displaying the page content. Should a visitor fail the check, the script can redirect to another page or display an “Access Denied” message.

2. Example File Structure

A minimal HTML file (s1.html) might appear as follows:

<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>s1.html - Client-Side Restricted Page</title>
    <script>
        function checkAccess() {
            // Simple prompt-based approach (not secure)
            var userResponse = prompt("Enter the secret code to view this page:");
            
            // Compare user input with the 'secret code'
            if (userResponse !== "SECRET123") {
                alert("Access Denied");
                window.location.href = "error.html"; 
            }
        }
    </script>
</head>
<body onload="checkAccess()">
    <h1>Secured Content</h1>
    <p>This is the protected content of s1.html.</p>
</body>
</html>

• onload="checkAccess()": Triggers the checkAccess function upon loading the page.
• prompt: Requests a password or code, which is compared to a hard-coded value, SECRET123.
• alert and window.location.href: Redirect the user if the check fails.

3. Possible Refinements

• Storing Credentials in localStorage: A script might store a token or pseudo-password in localStorage once the user is “validated.” Subsequent page loads would check for this token instead of re-prompting for credentials each time. However, this remains insecure, as localStorage is easily manipulated by knowledgeable users.
• Hiding Content with JavaScript: Instead of redirecting, some implementations dynamically hide page elements until access is confirmed. While feasible, the hidden content still exists in the page source code and is thus discoverable with minimal effort.
• Obfuscating the JavaScript: Basic obfuscation tools can convert the script into a less readable form. This measure adds a trivial layer of obscurity but does not offer true security.

4. Security Considerations

• View Source: Browsers allow viewing and editing of client-side code, making any embedded credentials or logic visible.
• Lack of Encryption: Communication of the “secret code” is not encrypted unless the page is served over HTTPS. Even then, the code is easily discovered in the HTML/JavaScript source.
• Easily Bypassed: A simple removal or modification of the JavaScript check will grant access, meaning a determined user can bypass client-side protection with little effort.

Written on December 16th, 2024

HTTP Basic Authentication in Nginx on macOS

HTTP Basic Authentication presents a straightforward means of safeguarding web content by prompting for user credentials before granting access. On macOS, Homebrew installations of Nginx provide a convenient environment to apply this security mechanism to specific files, such as s1.html and s2.html, or to entire websites. The following sections outline the installation of Nginx, creation of a password file, configuration for protecting individual pages or an entire domain, troubleshooting permission-related issues, and managing htpasswd for user credentials.

1. Generating a Password File

The .htpasswd file holds usernames and password hashes for HTTP Basic Authentication. Various tools can create and modify this file; htpasswd from the Apache utilities is a common choice.

1. Install Apache Utilities (if not already present):

   brew install httpd
   

2. Create the .htpasswd File in the Nginx configuration directory or another secure location:

   htpasswd -c /opt/homebrew/etc/nginx/.htpasswd exampleuser
   

   This command prompts for a password and generates a file that stores exampleuser's credentials in hashed form.

3. Set Appropriate Permissions to restrict unauthorized access:

   sudo chmod 640 /opt/homebrew/etc/nginx/.htpasswd
   sudo chown $(whoami):staff /opt/homebrew/etc/nginx/.htpasswd
   

2. Applying HTTP Basic Authentication to Individual Webpages

Securing specific files, such as s1.html and s2.html, involves adding location blocks within the server {} context in the Nginx configuration file. Typically, the main configuration file resides at /opt/homebrew/etc/nginx/nginx.conf.

1. Open the Configuration File:

   sudo emacs /opt/homebrew/etc/nginx/nginx.conf
   

2. Insert Location Directives for each page that requires protection. For instance:

   server {
       listen       80;
       server_name  example.com;
   
       location = /s1.html {
           auth_basic           "Restricted Content";
           auth_basic_user_file /opt/homebrew/etc/nginx/.htpasswd;
       }
   
       location = /s2.html {
           auth_basic           "Restricted Content - Page 2";
           auth_basic_user_file /opt/homebrew/etc/nginx/.htpasswd;
       }
   }
   

   • auth_basic defines the realm name shown in the authentication prompt.
   • auth_basic_user_file specifies the path to the .htpasswd file created earlier.
3. Save the Configuration and exit the text editor.

3. Applying HTTP Basic Authentication to the Entire Website

Instead of protecting individual files, the same directives may be placed in the main location / block to require credentials for all site resources:

server {
    listen 80;
    server_name example.com;

    location / {
        auth_basic           "Restricted Content";
        auth_basic_user_file /opt/homebrew/etc/nginx/.htpasswd;
    }
}

4. Managing the .htpasswd File

Adding or Modifying User Credentials

To add new users or update passwords for existing users in the same .htpasswd file, run htpasswd without the -c (create) flag (omitting -c prevents overwriting the file):

htpasswd /opt/homebrew/etc/nginx/.htpasswd newuser

Entering a new username with this command inserts a fresh record. Invoking it again for an existing username updates the corresponding password.

Removing Users

To remove a user, open .htpasswd in a text editor and delete the relevant line containing the username and hashed password:

sudo emacs /opt/homebrew/etc/nginx/.htpasswd

Each line follows the format:

username:hashedpassword

Removing the line effectively revokes access for that user.

5. Testing and Verification

1. Validate Nginx Configuration:

   sudo nginx -t

   Successful syntax checks display “syntax is ok” without emerg errors.

2. Restart Nginx:

   sudo brew services restart nginx

   This applies the new settings and ensures the PID file is properly handled by Homebrew.

3. Access Protected Pages:
   • Navigate to http://localhost/s1.html or http://localhost/s2.html.
   • Expect a login prompt. Enter valid credentials from the .htpasswd file to confirm proper authentication.

6. Troubleshooting Permission Errors

1. nginx -t

   Generates the following example error:

   nginx: the configuration file /opt/homebrew/etc/nginx/nginx.conf syntax is ok
   nginx: [emerg] open() "/opt/homebrew/var/run/nginx.pid" failed (13: Permission denied)
   nginx: configuration file /opt/homebrew/etc/nginx/nginx.conf test failed

   Though the syntax is correct, Nginx cannot access or create the PID file at /opt/homebrew/var/run/nginx.pid due to permission restrictions. The following steps often resolve the issue:

   1. Confirm Directory Existence:

      ls -ld /opt/homebrew/var/run/
      

      If the directory does not exist, create it:

      sudo mkdir -p /opt/homebrew/var/run/
      

   2. Adjust Ownership and Permissions:

      sudo chown -R $(whoami) /opt/homebrew/var/run/
      sudo chmod -R 755 /opt/homebrew/var/run/
      

   3. Use Homebrew Services

      Managing Nginx with Homebrew’s service commands ensures correct permissions and avoids conflicts:

      sudo brew services restart nginx

2. nginx -t

   Generates the following example error:

   nginx: the configuration file /opt/homebrew/etc/nginx/nginx.conf syntax is ok
   nginx: [emerg] open() "/opt/homebrew/etc/nginx/error.log" failed (13: Permission denied)
   nginx: configuration file /opt/homebrew/etc/nginx/nginx.conf test failed

   The following step may resolve the issue:

   sudo nginx -t

Written on December 16th, 2024

HTTP Basic Authentication Persistence in Nginx on macOS

HTTP Basic Authentication is a straightforward and stateless method of controlling access to web resources. When enabled in Nginx—particularly on macOS—this protocol prompts for a username and password. Once valid credentials are provided, browsers often cache them to minimize repeated prompts. However, administrators and users may be uncertain about how Nginx (and the system itself) handles caching, whether the server “remembers” specific IP addresses or browsers, and how to reset cached credentials. This integrated guide compiles and refines multiple perspectives on Basic Authentication, covering its mechanics, security implications, and methods to reset cached credentials on macOS.

1. Clarification on HTTP Basic Authentication Persistence in Nginx

Nature of HTTP Basic Authentication

1. Statelessness
   • The mechanism does not maintain sessions. Each request to a protected resource must include the Authorization header containing Base64-encoded credentials.
   • The server (Nginx) treats each request independently.
2. Credential Transmission
   • Base64 encoding is used, but without encryption. HTTPS is strongly recommended to prevent credential interception.
   • Browsers typically auto-include the Authorization header for subsequent requests within the same session.
3. Security Considerations
   • Use TLS/SSL (HTTPS) to protect credentials in transit.
   • Without HTTPS, credentials can be intercepted, decoded, and exploited by malicious actors.
   • Basic Authentication on its own does not offer session management, token-based features, or multi-factor workflows.

2. Persistence of Authorized IP Addresses and Web Browsers

No IP-Based Authorization Memory

• No Built-In IP Tracking
  • Nginx’s Basic Authentication module does not record or store IP addresses. Authorization decisions are based solely on the validity of the credentials in the Authorization header.
• Separate IP-Based Access Control
  • IP-based allow/deny directives can be configured, but these are distinct from Basic Authentication and require explicit settings. For example, allow and deny directives can be added to the server block. This functionality does not integrate with Basic Authentication caching.

Browser Credential Caching

• Session Caching
  • Browsers cache the provided username and password for the duration of the browsing session. This explains why a prompt appears once, and subsequent requests do not require the user to re-enter credentials.
• Inherent Browser Behavior
  • Each request from the same browser session automatically includes the saved credentials. Closing or restarting the browser (or entering private/incognito mode) typically clears or bypasses that cache.
• No Server Memory of Browser Type
  • Nginx does not track which browser or version a user is running. Authentication depends strictly on the credentials passed via the HTTP request headers.

3. Understanding Credential Persistence on macOS

How Credential Persistence Works

1. Browser Credential Caching
   • Modern browsers store credentials for the session, preventing repeated prompts.
   • The credentials remain cached until the session ends or the user clears browsing data.
2. Impact of Changing Computers or Browsers
   • Credentials entered on one machine do not carry over to another.
   • Different browsers on the same computer maintain separate caches. Using a different browser triggers a fresh login prompt.
3. IP Address Considerations
   • Stateless Authentication: Basic Authentication itself is not dependent on IP addresses.
   • Optional IP Restrictions: Nginx can be configured to permit or deny access from specified IPs, but this is a separate mechanism from Basic Authentication.

Security Implications

1. Convenience vs. Security
   • Browser caching reduces repeated prompts, improving user experience.
   • If a device is shared and credentials are cached, unauthorized users might gain access to protected resources.
2. Mitigation Strategies
   • Always enable HTTPS to encrypt credentials in transit.
   • Consider session-based or token-based authentication for advanced security needs (e.g., session expiration, multi-factor authentication).
3. Credential Updates
   • Modifying, adding, or removing authorized users is managed within the Nginx .htpasswd file. Updates immediately impact all clients attempting to access the resource.

4. Implications for Security and Management

1. No Permanent Memory of Clients
   • Because Basic Authentication is stateless, Nginx does not retain any memory or state about individual clients. Authentication is validated upon each request.
2. Enhanced Security Practices
   • Use HTTPS: Ensures credentials are not easily intercepted.
   • Consider More Advanced Authentication: For applications needing detailed session management or more robust security, methods such as OAuth, JWT, or other token-based systems are recommended.
3. Managing Credentials
   • Updates to the .htpasswd File: Revising user credentials in the .htpasswd file is necessary for changing access privileges.

5. Resetting Credential Caching in Nginx on macOS

Resetting credential caching ensures proper functionality when testing or validating HTTP Basic Authentication. Confirming the browser re-prompts for credentials is crucial when verifying security setups.

5.1. Use a Private/Incognito Window

Opening the protected resource in a private or incognito window prevents the browser from using previously cached credentials.

• Google Chrome: File → New Incognito Window or Command + Shift + N
• Mozilla Firefox: File → New Private Window or Command + Shift + P
• Safari: File → New Private Window or Command + Shift + N
• Microsoft Edge: File → New InPrivate Window or Command + Shift + N

5.2. Clear Browser Cache and Stored Credentials

Clearing cached data forces the browser to request new credentials:

Google Chrome

1. Settings → Privacy and security → Clear browsing data
2. Select All time and check Cookies and other site data and Cached images and files
3. Confirm by selecting Clear data

Mozilla Firefox

1. Settings → Privacy & Security → Cookies and Site Data → Clear Data
2. Check Cookies and Site Data and Cached Web Content

Safari

1. Safari (menu) → Preferences → Privacy → Manage Website Data → Remove All
2. Alternatively, remove only data for the specific site

Microsoft Edge

1. Settings → Privacy, search, and services → Choose what to clear
2. Select All time and check Cookies and other site data and Cached images and files

5.3. Restart the Browser

Completely closing the browser and reopening it may remove session-level cached credentials.

5.4. Use Different Browsers or Devices

Testing access from alternate browsers (Chrome vs. Firefox vs. Safari, etc.) or different devices ensures the credentials cache on one setup does not affect another.

• Different Browsers: If initially using Chrome, try accessing the protected page with Firefox, Safari, or Edge.
• Different Devices: Access the protected page from another computer or mobile device to ensure that the authentication prompt appears as expected.

5.5. Clear Saved Passwords (If Applicable)

Some browsers can store Basic Authentication credentials in their password managers:

• Google Chrome: Settings → Autofill → Passwords → Remove relevant entries
• Mozilla Firefox: Settings → Privacy & Security → Saved Logins → Remove relevant entries
• Safari: Safari → Preferences → Passwords → Remove relevant entries
• Microsoft Edge: Settings → Profiles → Passwords → Remove relevant entries

5.6. Restart the Computer

Restarting macOS ensures all system processes (including the browser) terminate, clearing any stored authentication in RAM.

1. Save all work and close applications.
2. Restart the macOS system.
3. Open the browser and navigate to the protected webpage.

Written on December 17th, 2024

Token-Based Authentication

Token-based authentication (commonly using JSON Web Tokens, JWT) allows stateless verification of client requests. On macOS, Homebrew streamlines the installation of essential tools—such as Nginx, Python, and Node.js—while Emacs can serve as a capable text editor. When combined with HTTPS, token-based authentication ensures that credentials and tokens remain encrypted in transit. Below is a refined guide structured for macOS users leveraging Homebrew, Emacs, and Nginx.

1. Prerequisites

1. Homebrew
   • Ensure Homebrew is installed on macOS:

     bash /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

2. Nginx
   • Install via Homebrew:

     brew install nginx

3. Python 3 and Node.js
   • Python (system version may already be present, but Homebrew provides the latest):

     brew install python        

   • Node.js:

     brew install node

4. Emacs (Optional)
   • If Emacs is not already installed:

     brew install emacs

   • Open Emacs to edit configuration or application files with:

     emacs filename

5. SSL/TLS Certificates
   • Acquire SSL/TLS certificates (e.g., self-signed for development or from Let’s Encrypt for production).
6. JWT Libraries
   • Python: PyJWT
   • Node.js: jsonwebtoken

2. Configure Nginx for HTTP and HTTPS

1. Nginx Homebrew Location
   • Homebrew usually places the main configuration file in /usr/local/etc/nginx/nginx.conf or /opt/homebrew/etc/nginx/nginx.conf depending on the Apple Silicon or Intel environment.
2. Generate or Obtain SSL Certificates
   • For testing (self-signed):

     openssl req -x509 -newkey rsa:4096 -sha256 -days 365 -nodes \
       -keyout server.key -out server.crt        

   • Place server.crt and server.key in a secure folder (e.g., /usr/local/etc/nginx/ssl/).
3. Create or Edit the Nginx Configuration
   • Open nginx.conf in Emacs:

     emacs /usr/local/etc/nginx/nginx.conf        

   • Insert a server block for HTTPS:

     server {
         listen 443 ssl http2;
         server_name example.local;
     
         ssl_certificate /usr/local/etc/nginx/ssl/server.crt;
         ssl_certificate_key /usr/local/etc/nginx/ssl/server.key;
     
         location / {
             proxy_pass http://127.0.0.1:5000; # Adjust for Python or Node.js server port
             proxy_http_version 1.1;
             proxy_set_header Upgrade $http_upgrade;
             proxy_set_header Connection "upgrade";
             proxy_set_header Host $host;
         }
     }
     
     server {
         listen 80;
         server_name example.local;
         return 301 https://$host$request_uri;
     }        

4. Reload or Restart Nginx

   brew services restart nginx        

   • Alternatively, to run Nginx manually:

     nginx -s reload        

3. Implement JWT Logic

JWT is language-agnostic and can be implemented in Python or Node.js. Any editing can be done through Emacs.

3.1. Node.js (server.js)

1. Initialize Project

   mkdir node-jwt-app && cd node-jwt-app
   npm init -y
   npm install express jsonwebtoken body-parser        

2. Create Server File (server.js)

   emacs server.js        

   const express = require('express');
   const jwt = require('jsonwebtoken');
   const bodyParser = require('body-parser');
   const app = express();
   
   app.use(bodyParser.json());
   
   const SECRET_KEY = 'replace_with_secure_key';
   
   // Login endpoint issues JWT
   app.post('/login', (req, res) => {
       const { username, password } = req.body;
       // Validate credentials here (e.g., check database)
       if (username === 'demo' && password === 'demo') {
           const token = jwt.sign({ user: username }, SECRET_KEY, { expiresIn: '1h' });
           return res.json({ token });
       }
       return res.status(401).send('Unauthorized');
   });
   
   // Middleware to verify token
   function verifyToken(req, res, next) {
       const bearerHeader = req.headers['authorization'];
       if (!bearerHeader) {
           return res.status(403).send('No token provided');
       }
       const token = bearerHeader.split(' ')[1];
       jwt.verify(token, SECRET_KEY, (err, decoded) => {
           if (err) {
               return res.status(403).send('Token invalid or expired');
           }
           req.user = decoded.user;
           next();
       });
   }
   
   // Protected route
   app.get('/protected', verifyToken, (req, res) => {
       return res.send(`Access granted. Welcome, ${req.user}`);
   });
   
   app.listen(5000, () => {
       console.log('Node.js JWT server running on port 5000');
   });        

3. Start Node.js App

   node server.js        

4. Verify with HTTP or HTTPS
   • Send a POST request to /login over HTTPS.
   • Provide valid credentials to obtain a JWT.
   • Include the token in Authorization: Bearer <token> for protected endpoints.

3.2. Python (Flask: app.py)

1. Setup Virtual Environment

   brew install python   # if not installed
   python3 -m venv venv
   source venv/bin/activate
   pip install flask PyJWT        

2. Create Server File (app.py)

   emacs app.py        

   from flask import Flask, request, jsonify
   import jwt
   import datetime
   
   app = Flask(__name__)
   SECRET_KEY = 'replace_with_secure_key'
   
   @app.route('/login', methods=['POST'])
   def login():
       data = request.json
       username = data.get('username')
       password = data.get('password')
   
       # Validate username/password (e.g., checking a database)
       if username == 'demo' and password == 'demo':
           token = jwt.encode(
               {
                   'user': username,
                   'exp': datetime.datetime.utcnow() + datetime.timedelta(hours=1)
               },
               SECRET_KEY,
               algorithm='HS256'
           )
           return jsonify({'token': token})
       return 'Unauthorized', 401
   
   def verify_token(token):
       try:
           payload = jwt.decode(token, SECRET_KEY, algorithms=['HS256'])
           return payload['user']
       except jwt.ExpiredSignatureError:
           return None
       except jwt.InvalidTokenError:
           return None
   
   @app.route('/protected', methods=['GET'])
   def protected():
       auth_header = request.headers.get('Authorization')
       if not auth_header:
           return 'No token provided', 403
       token = auth_header.split(" ")[1]
       user = verify_token(token)
       if not user:
           return 'Token invalid or expired', 403
       return f'Access granted. Welcome, {user}'
   
   if __name__ == '__main__':
       app.run(port=5000)        

3. Start Python Flask App

   python app.py        

4. Verify HTTPS Handling
   • Ensure Nginx proxies inbound HTTPS requests to port 5000.
   • Obtain tokens through the /login route and include them in Authorization headers for /protected calls.

4. Testing and Validation

1. Nginx Logs
   • Monitor /usr/local/var/log/nginx/access.log and /usr/local/var/log/nginx/error.log for HTTP status codes and error messages.
2. API Client Tools
   • Use tools like curl, Postman, or HTTPie to confirm successful token issuance and token-based access to protected endpoints.
   • Verify calls proceed over HTTPS by specifying https://example.local/login or similar domain.
3. Emacs for Ongoing Edits
   • Continue to manage configuration files (nginx.conf, server.js, app.py) from Emacs.
   • Reload Nginx and restart the Node.js or Flask application as code changes are made.

5. Best Practices

1. Encryption
   • Always serve content over HTTPS.
   • Use strong ciphers and modern SSL protocols.
2. JWT Security
   • Use robust secrets (e.g., environment variables) or a dedicated key management system.
   • Employ short token expiration times.
   • Consider implementing token refresh strategies and revocation lists for enhanced security.
3. Version Control
   • Keep configuration files (e.g., nginx.conf, application files) under version control (Git) for rollbacks and collaboration.
4. Scaling
   • Stateless JWT flows simplify horizontal scaling, as each server node only needs the same signing key.
   • Ensure load-balancer or reverse proxy configurations remain consistent.

Written on December 17th, 2024

Exploring Alternatives to NAS Solutions

Synology NAS vs. Custom Linux FTP Server

This guide offers a thorough comparison between Network Attached Storage (NAS) devices, such as Synology NAS, and custom-built Linux FTP servers. It carefully examines their features, security protocols, ease of use, and other essential factors to support well-considered decisions on secure and efficient data storage. Additionally, it provides a comparative overview of Synology NAS models, recommends suitable hard drives, outlines other NAS competitors, and presents insights into RAID configurations and best practices for enhancing server security when accessed externally.

NAS vs. Custom Linux FTP Servers

Network Attached Storage (NAS)

NAS devices are dedicated file storage units connected to a network, allowing multiple users and client devices to retrieve data from centralized disk capacity. Synology NAS stands out with its user-friendly interface, robust security features, and a range of applications for various needs.

• Ease of Use: Simplifies setup and management with an intuitive interface.
• Integrated Security Features: Offers built-in encryption, regular updates, and security applications.
• Additional Applications: Provides multimedia streaming, backup solutions, and cloud synchronization.
• Community and Support: Extensive documentation and an active user community for assistance.

Custom Linux FTP Server

Setting up a custom FTP server on Linux offers greater control and flexibility over system configurations and software choices. This option is ideal for users with advanced technical skills who require a tailored environment for specific applications.

• Flexibility: Full control over software and hardware configurations.
• Customization: Ability to tailor the system to specific needs, including custom scripts and applications.
• Cost Efficiency: Potentially lower initial costs if repurposing existing hardware.

Security Considerations

Data Security in Synology NAS

Synology NAS devices come equipped with the DiskStation Manager (DSM) operating system, offering multiple layers of security:

• Encryption: Supports data encryption at rest, securing stored files even if physical disks are compromised.
• Secure Protocols: Utilizes FTPS, SFTP, and HTTPS to encrypt data during transmission.
• Multi-Factor Authentication (MFA): Adds extra security by requiring multiple verification methods.
• Regular Updates: Provides timely firmware and software updates to patch vulnerabilities.
• Snapshot and Versioning: Allows point-in-time recovery of data, protecting against accidental deletions or ransomware attacks.

Security in Custom Linux FTP Servers

While a Linux FTP server can be secured, it requires manual configuration:

• Secure Protocols: Implementation of SFTP or FTPS to encrypt data during transfer.
• Firewall Configuration: Requires setting up firewalls to protect against unauthorized access.
• System Hardening: Involves manual updates and security patches to maintain system integrity.
• User Access Control: Needs careful management of user permissions and access rights.

Protocols and Their Security Implications

A variety of file transfer protocols are available, each with strengths and weaknesses. The following table compares these protocols to aid in selecting the most appropriate one for specific needs.

Synology Drive

• Security: Encrypted connections, end-to-end encryption, and multi-factor authentication.
• Features: File versioning, cross-device synchronization, collaboration tools.
• Advantages: Seamless integration within the Synology ecosystem, enhanced security features.

FTP/SFTP

• FTP: Lacks encryption, making it vulnerable to interception.
• SFTP: Secure alternative using SSH for encrypted data transfer.
• Advantages: Widely supported and suitable for secure file transfers outside proprietary systems.

Synology NAS vs. Competitors

Several notable competitors provide NAS solutions with varying features, performance, and price points.

*Relative Pricing: Low (< $300), Moderate ($300 - $600), High (> $600)

Synology NAS Models Comparison

2-Bay Synology NAS Models Side-by-Side Comparison: DS223j vs. DS224+

• "j": Entry-level models aimed at basic functionality and affordability, typically for home use.
• "+": Higher-end models designed for enhanced performance, advanced features, and expandability, suitable for small businesses or advanced users.

RAID 1 Compatibility: Both models support RAID 1 configurations, allowing data mirroring across the two bays for redundancy and protection against data loss due to drive failure.

DS223j: Ideal for home users seeking a budget-friendly option for basic file storage and backups. It offers essential features but lacks the performance of higher-end models.

DS224+: Suited for small offices and advanced home users requiring enhanced performance, multimedia streaming, and expandability. Its more powerful CPU and expandable RAM make it versatile for demanding tasks.

Hard Drive Recommendations for NAS

Selecting the right hard drives is crucial for NAS performance and reliability. Drives designed specifically for NAS environments are recommended due to their enhanced durability and features.

Considerations When Choosing HDDs:

• NAS-Specific Drives: Regular desktop drives are not recommended due to lower reliability in NAS environments.
• Workload Rate: Ensure the drive supports the required workload rate for continuous operation.
• Capacity Needs: Balance between current storage needs and future expansion.
• Warranty and Support: Consider drives with longer warranties for added peace of mind.

Detailed Comparison of 8TB Hard Drives

The table below provides a comprehensive comparison of five 8TB drives from Seagate, Western Digital, and Synology, each offering unique features for different usage environments. This comparison includes key technical specifications, workload ratings, and other features to assist in selecting the most appropriate drive for NAS, enterprise, or desktop use.

• Best for NAS: The Seagate IronWolf ST8000VN004 and Western Digital Red Plus WD80EFZZ are ideal for NAS applications, particularly in small to medium-sized setups. Both drives are optimized for 24×7 operation and include NAS-specific firmware (AgileArray for Seagate, NASware 3.0 for WD), enhancing compatibility and reliability within NAS environments.
• Best for Synology NAS: For Synology NAS systems, the Synology HAT3310 offers seamless integration with Synology’s DiskStation Manager (DSM), making it the most compatible option. As an enterprise-grade drive, it also ensures durability and performance in demanding conditions.
• Best for High Workloads and Enterprise Use: The Western Digital Ultrastar WD80EAAZ is designed for data centers and high-demand enterprise environments, with a high workload rating (550TB/year) and advanced vibration protection, which are essential for continuous, intensive RAID configurations.
• Avoid Desktop Drives in NAS: While the Seagate Barracuda ST8000DM004 offers high capacity at a lower price, it lacks NAS-specific optimizations and vibration protection, essential for multi-drive NAS environments. This drive is better suited to desktop or single-drive environments rather than NAS use.

Detailed Comparison of 8TB Hard Drives

Seagate Barracuda ST8000DM004: Designed primarily for desktop use, this drive offers high capacity at a competitive price. It operates at 5400 RPM and is suitable for standard workloads. However, it lacks the features optimized for NAS environments, such as vibration resistance and firmware tailored for RAID configurations.

Western Digital Red Plus WD80EFZZ: Specifically engineered for NAS systems with up to 8 bays, this drive includes NASware 3.0 technology, enhancing reliability and compatibility. It operates at 5640 RPM and supports 24×7 operation, making it well-suited for continuous use in NAS setups.

Seagate IronWolf ST8000VN004: Built for NAS applications, this drive features AgileArray technology for optimized NAS performance. With a rotational speed of 7200 RPM, it offers higher performance, and supports continuous 24×7 operation. It includes vibration sensors to maintain reliability in multi-drive systems.

Synology HAT3310: An enterprise-grade hard drive designed by Synology for seamless integration with its NAS systems. Operating at 7200 RPM, it is optimized for use with Synology's DiskStation Manager (DSM) software. It offers high reliability and performance, tailored specifically for Synology NAS environments.

• Best for NAS: Western Digital Red Plus and Seagate IronWolf are ideal for most NAS setups due to their NAS-specific optimizations.
• Synology Integration: Synology HAT3310 is recommended for users seeking maximum compatibility and performance with Synology NAS systems.
• Avoid Desktop Drives: Using desktop drives like the Seagate Barracuda in a NAS is not recommended due to potential reliability issues.

Common RAID Configurations for Data Storage

Redundant Array of Independent Disks (RAID) technology combines multiple disk drives to enhance redundancy, improve performance, or both. Below are commonly used RAID levels and their primary attributes.

RAID 0 (Striping)

Data is striped across multiple disks without redundancy, enhancing performance but offering no data protection. Suitable for scenarios where speed is prioritized over data security.

RAID 1 (Mirroring)

Data is duplicated across disks, providing high redundancy. Ideal for critical data storage where data loss prevention is essential. Requires identical disks for optimal performance.

Using two identical disks is optimal for RAID 1 configurations to ensure:

• Optimal Performance: Consistent read/write speeds without bottlenecks.
• Storage Efficiency: Full utilization of disk capacity.
• Reliability: Similar durability and lifespan reduce failure risks.
• Ease of Maintenance: Simplifies replacement and ensures compatibility.

RAID 5 (Striping with Parity)

Data and parity are distributed across at least three disks, allowing recovery from a single disk failure. Balances performance, storage efficiency, and redundancy.

RAID 6 (Striping with Double Parity)

Similar to RAID 5 but with double parity, tolerating up to two disk failures. Suitable for enterprise storage requiring high data protection.

RAID 10 (Combination of RAID 1 and RAID 0)

Combines mirroring and striping, requiring at least four disks. Offers high performance and redundancy but at a higher cost and reduced storage efficiency.

Enhancing Security for Servers with External IP Access

When exposing a server to the internet via an external IP address, several measures should be implemented to enhance security:

Security Measures

1. Firewall and Port Restrictions:
   • Allow only necessary ports and services.
   • Implement IP whitelisting where possible.
2. Authentication and Access Control:
   • Enforce strong passwords and multi-factor authentication (MFA).
   • Use SSH key-based authentication and disable root login.
   • Implement role-based access control (RBAC).
3. VPN for Secure Remote Access:
   • Set up a VPN to prevent direct exposure to the internet.
4. Data Encryption (SSL/TLS):
   • Use SSL/TLS certificates for web services.
   • Encrypt all remote connections.
5. Regular Updates and Patching:
   • Keep the operating system and software up to date.
   • Enable automatic updates for critical patches.
6. Change Default Ports and Disable Default Accounts:
   • Change default service ports to non-standard ports.
   • Disable or rename default admin accounts to reduce attack vectors.

NAS Setup Without a Dedicated Computer

A NAS device does not require a dedicated computer and can operate as a standalone unit connected directly to a router.

Connecting NAS to a Router

• Direct Connection: Connect the NAS to the router via Ethernet, making it accessible to all network devices.
• Internet Access: The NAS can access the internet through the router for remote access and cloud services.
• Router's Bandwidth: Utilizes the router's capacity for efficient data transfer across the network and internet.
• Advantages: Provides centralized storage, reduces complexity, and leverages the router's capabilities without needing a dedicated computer.

Upgrading RAM in Synology DS224+

Expanding the RAM in the DS224+ can enhance performance for multitasking and handling larger data volumes.

Compatible RAM Module

• Synology D4NESO-2666-4G: 4GB DDR4-2666 Non-ECC SO-DIMM (official Synology module).

Specifications

• Type: DDR4 Non-ECC SO-DIMM.
• Speed: 2666 MHz.
• Maximum Supported Memory: Up to 6GB total (2GB built-in + 4GB expansion).

Using official Synology memory modules is recommended to ensure compatibility and support.

Written on October 29th, 2024

Setting Up a Mac mini with Nginx as a Combined Web and File Server

Configuring a Mac mini to function as both a web server and a file server using Nginx optimizes resource utilization and enhances accessibility. This guide provides a structured approach to integrating file-sharing capabilities into the existing Nginx web server setup, ensuring secure and efficient access from macOS and Windows devices.

• Objective: Reuse the current Nginx web server on the Mac mini to serve files, effectively creating a personal file server.
• Benefits: Centralized management, efficient use of existing resources, and simplified access to files over the network or internet.

Step 1: Verify the Existing Nginx Web Server Setup

Ensure that the Nginx server on the Mac mini is properly configured and operational.

• Check Server Status:
  • Open a web browser and navigate to http://localhost or the Mac mini's IP address.
  • Confirm that the default web page or any existing hosted content is visible.

Step 2: Organize Files for Sharing

• Locate the Nginx Document Root:
  • The default Nginx document root is typically located at /usr/local/var/www or another specified directory in the Nginx configuration file (/usr/local/etc/nginx/nginx.conf).
  • To confirm, open the Nginx configuration file and locate the root directive, which indicates the document root.
• Create a Directory for Shared Files:
  • Within the document root, create a new folder to store files for sharing:

  mkdir /usr/local/var/www/shared_files

  • Organize files into subdirectories if needed for easy navigation.
• Add Files to the Directory:
  • Copy or move files into the shared_files directory.
  • Organize further into subdirectories if desired.

Step 3: Adjust Permissions

• Set Read Permissions:
  • Ensure that the Nginx server has the appropriate permissions to serve the files.
  • In Terminal, adjust the directory permissions:

  sudo chmod -R o+rX /usr/local/var/www/shared_files

  • This command grants read access to others, allowing the web server to serve the files.

Step 4: Configure Nginx to Allow Directory Listing (Optional)

• Modify Nginx Configuration:
  • Open the Nginx configuration file in a text editor:

  sudo emacs /usr/local/etc/nginx/nginx.conf

  • Add the following location block to configure directory listing for the shared_files folder:

  location /shared_files/ {
      autoindex on;
      alias /usr/local/var/www/shared_files/;
  }

  • Save the changes and exit the editor.
• Restart Nginx:
  • Apply changes by restarting Nginx:

  sudo nginx -s reload

Step 5: Accessing the Shared Files

• Local Access:
  • On the same network, open a web browser and enter http://[Mac_mini_IP]/shared_files/ to access files.
• Remote Access:
  • If remote access is required, configure the router to allow external connections to the Mac mini’s IP on port 80 (HTTP) or port 443 (HTTPS if SSL is enabled).
  • Consider setting up a Dynamic DNS (DDNS) service to assign a domain name to the Mac mini's IP, facilitating easier remote access.

Step 6: Implementing Security Measures

• Basic Authentication:
  • Enable basic password protection by creating a .htpasswd file and configuring Nginx for restricted access.
  • Create Password File:
    • Execute the following command in Terminal to create a password file:

    sudo htpasswd -c /usr/local/etc/nginx/.htpasswd username

    • Enter the password when prompted.
    • For additional users, omit the -c flag to avoid overwriting the file:

    sudo htpasswd /usr/local/etc/nginx/.htpasswd anotheruser

  • Update Nginx Configuration:
    • Add authentication to the location block for shared_files:

    location /shared_files/ {
        autoindex on;
        alias /usr/local/var/www/shared_files/;
        auth_basic "Restricted Access";
        auth_basic_user_file /usr/local/etc/nginx/.htpasswd;
    }

    • Save and exit the configuration file.
  • Restart Nginx:
    • Apply changes by restarting Nginx:

    sudo nginx -s reload

• Enable HTTPS for Secure Access (Optional):
  • To encrypt access, set up SSL by obtaining an SSL certificate (e.g., from Let’s Encrypt) and configuring Nginx for HTTPS.
  • Obtain SSL Certificate:
    • Use a service like Let's Encrypt to obtain a free SSL certificate.
  • Configure Nginx for SSL:
    • Edit the Nginx configuration to include SSL settings within the server block:

    server {
        listen 443 ssl;
        server_name your_domain.com;
    
        ssl_certificate /path/to/fullchain.pem;
        ssl_certificate_key /path/to/privkey.pem;
    
        location /shared_files/ {
            autoindex on;
            alias /usr/local/var/www/shared_files/;
            auth_basic "Restricted Access";
            auth_basic_user_file /usr/local/etc/nginx/.htpasswd;
        }
    }

    • Save the changes.
  • Restart Nginx:
    • Apply the changes by restarting Nginx:

    sudo nginx -s reload

Step 7: Alternative File Access Methods (SMB)

• Enable SMB File Sharing:
  • Consider enabling SMB (Server Message Block) protocol for file sharing alongside HTTP.
  • Activate File Sharing:
    • Open System Preferences > Sharing and check the box next to File Sharing.
  • Configure Shared Folders:
    • Click the Options button and ensure that Share files and folders using SMB is selected.
    • Add the shared_files folder to the list of shared folders.
  • Set Permissions:
    • Specify user access levels (Read Only, Read & Write) for each shared folder.
  • Access via SMB:
    • On macOS, access via Finder by navigating to smb://[Mac_mini_IP]/shared_files.
    • On Windows, open File Explorer and enter \\[Mac_mini_IP]\shared_files.

Step 8: Remote Access Configuration

• Dynamic DNS Setup:
  • Register with a DDNS provider to associate a domain name with the Mac mini's IP address.
• Router Configuration:
  • Port Forwarding:
    • Forward necessary ports (e.g., 80 for HTTP, 443 for HTTPS, 445 for SMB) to the Mac mini's local IP address.
  • Firewall Settings:
    • Adjust firewall settings to allow incoming connections on the forwarded ports.

Step 9: Maintenance and Monitoring

• Regular Updates:
  • Keep macOS and Nginx updated to the latest versions to ensure security and performance.
• Monitor Logs:
  • Check Nginx logs located in /usr/local/var/log/nginx/access.log and /usr/local/var/log/nginx/error.log for any errors or unauthorized access attempts.
• Backup:
  • Regularly back up shared files and Nginx configurations to prevent data loss.

Written on November 10th, 2024

DS723+

Synology DS723+ Expansion and Configuration

The Synology DS723+ is a versatile 2-bay Network Attached Storage (NAS) device, ideally suited for the needs of small to medium-sized businesses. It offers options to expand and enhance its capabilities. This guide outlines the steps to expand storage capacity, optimize performance using SSD caching, compare it with similar NAS models, and mitigate data risks.

Expanding DS723+ Storage with Synology DX517

The DS723+ provides seamless expansion through Synology's DX517 expansion unit. The DX517 offers five additional drive bays, expanding the DS723+ to a total of seven bays, thereby enabling significant storage growth.

Purchase and Connect the DX517: The DX517 connects to the DS723+ via an eSATA cable and integrates into the Synology DiskStation Manager (DSM) environment. This setup offers plug-and-play functionality, allowing for immediate use and management.

Setup in DSM: Upon connecting the DX517, access the Storage Manager within DSM. The new drives will be detected, permitting configuration for additional storage volumes, RAID arrays, or backup purposes. DSM supports flexible RAID configurations, enabling the expansion of existing RAID volumes (where compatible) or the creation of new volumes with various RAID types for enhanced data security or performance.

Supported Configurations: The DX517 can be configured to support RAID levels compatible with the DS723+, offering flexibility for tasks such as archiving or high-performance storage.

Advantages of DX517 Expansion:

• Enhanced Storage Capacity: Adding five more bays allows substantial storage expansion and provides increased data redundancy options with RAID.
• Seamless Integration: Managed directly through DSM, the DX517 operates as if it were a native part of the NAS.
• Hot-Swappable Drives: Drives in the DX517 can be replaced without downtime, facilitating maintenance and drive upgrades.

DS723+ SSD Caching Options

The DS723+ includes two M.2 NVMe slots specifically designed for SSD caching, which enhances performance in data-intensive environments:

• Synology SNV3400 Series: Available in 400GB and 800GB models, these SSDs offer high endurance and reliability, optimized for NAS environments.
• Third-Party Options: While third-party SSDs in the M.2 2280 NVMe form factor may be used, Synology’s SNV3400 is recommended for optimal DSM integration and reliability.

Installation and Setup: After inserting the SSDs into the M.2 slots, access Storage Manager > SSD Cache in DSM to configure the cache in read-only mode (for single SSDs) or read-write mode (for dual SSDs), based on performance requirements and risk tolerance.

When to Use SSD Caching

• High Read-Write Workloads: Applications involving large file access, databases, or virtual machines benefit from SSD caching by reducing latency.
• Multi-User Environments: Environments accessed by multiple users experience minimized bottlenecks through faster data retrieval.
• Data-Heavy Applications: Demanding applications such as video editing or rendering gain increased speed and responsiveness.

When SSD Caching May Not Be Necessary

For users primarily utilizing the DS723+ for simple file storage, backups, or as a media server, the benefits of SSD caching are minimal, as standard HDDs can effectively handle such tasks.

Recommendations:

• For High Performance: Pairing the DS723+ with Synology SNV3400 SSDs in a read-write configuration can effectively support demanding workloads.
• For Data Safety: A read-only cache enhances read speed without the data loss risks inherent to write caching.

Ensuring Data Integrity with SSD Caching

SSD caching in write-cache mode presents certain risks, such as data corruption during unexpected shutdowns. Understanding these risks and implementing preventive measures is essential.

Potential Causes of Data Corruption

• Power Outages: During a power loss, data temporarily stored in the write cache may be lost.
• SSD Endurance and Failure: High write intensities can wear down SSDs, potentially leading to data inconsistency.
• System Crashes: Incomplete data transfers due to crashes can result in corrupted or unusable files.

Mitigating Data Risks

• Use ECC RAM: ECC (Error-Correcting Code) RAM, included in the DS723+, corrects minor errors in memory and is essential for data integrity in caching environments.
• Enable Uninterruptible Power Supply (UPS): A UPS provides backup power, allowing the DS723+ to complete cache-to-disk transfers during power loss.
• Select High-Endurance SSDs: Synology’s SNV3400 series includes power loss protection and high endurance, mitigating write failures.
• Opt for Read-Only Caching: For read-heavy applications, read-only caching enhances speed without the write-cache risks, reducing the likelihood of corruption.
• Regularly Monitor SSD Health: DSM offers health monitoring tools to track SSD wear, facilitating timely replacements when necessary.
• Maintain Scheduled Backups: Regular data backups provide recovery options in case of hardware failure, offering an additional layer of protection beyond caching.

Comparison of Synology DS224+, DS723+, DS423+, and DS923+

The following comparison highlights four Synology NAS models, emphasizing their unique features and ideal use cases:

• DS224+: A cost-effective solution for home or small office use, featuring 4K transcoding and moderate performance for basic tasks.
• DS423+: Suited for small offices with increased storage needs, providing four drive bays for larger media collections or shared files.
• DS723+: Ideal for advanced users or small businesses requiring high-performance storage and expandability, suitable for virtualization and intensive applications.
• DS923+: Excellent for medium businesses necessitating high-capacity storage, supporting up to nine bays and equipped with features for virtualization and high-demand environments.

Written on October 31st, 2024

Optimizing Synology DiskStation DS723+ with Memory and Cache Upgrades

The Synology DiskStation DS723+ is a versatile and upgradeable NAS solution, ideal for users seeking to enhance performance, responsiveness, and data handling efficiency. By upgrading both the RAM and SSD cache, the DS723+ can better handle demanding applications and deliver improved system functionality. The following offers a refined guide to optimizing the DS723+ with recommended memory and cache upgrades.

Memory (RAM) Upgrades: Specifications and Benefits

The DS723+ comes equipped with 2 GB of DDR4 ECC SODIMM memory by default. This can be expanded up to 32 GB by utilizing two memory slots, supporting a maximum of 16 GB per slot. The recommended specifications are:

Type and Voltage

• Type: DDR4-2666 ECC Unbuffered SODIMM, 260-pin
• Voltage: 1.2V

Recommended Memory Brands

• Synology: The D4ES01-16G (16 GB) module is Synology’s official option, tailored for optimal performance and seamless integration.
• Kingston: The Kingston Server Premier 16 GB DDR4-2666 ECC SODIMM (KSM26SED8/16HD) is widely compatible with the DS723+ and offers reliable performance.
• Crucial: The Crucial 16 GB DDR4-2666 SODIMM (CT16G4SFD8266) is also known to function effectively within this system.

Users may choose to upgrade gradually by replacing the pre-installed 2 GB module with a single 16 GB module now, with the flexibility to add a second 16 GB module in the future to reach the 32 GB limit. Additional memory enables the DS723+ to handle increased workloads, improve multitasking, and enhance performance for virtual machines, Docker containers, and high-demand applications, offering smoother system operation and faster response times.

NVMe SSD Cache Upgrades: Specifications and Expected Improvements

The DS723+ includes two M.2 2280 NVMe SSD slots for optional SSD caching or high-speed storage expansion. Unlike the memory, there is no pre-existing SSD cache included with the DS723+, leaving these slots available for users who wish to enhance data access speeds. Synology recommends using their SNV3400 series NVMe SSDs for compatibility and optimal performance. The SNV3400 series is available in:

Available Capacities

• 400 GB and 800 GB capacities

Installing two equal-sized SNV3400 SSDs in the DS723+ provides several advantages:

1. Enhanced Data Access with SSD Caching

Using two SSDs as a read-write cache reduces latency and improves access times, especially for frequently accessed files. This is beneficial for users who require fast data retrieval in applications such as database hosting, file sharing, and multimedia streaming.

2. System Resilience with RAID Configurations

Configuring two SSDs in a RAID 1 setup offers data redundancy, protecting against data loss in case of drive failure. Alternatively, the SSDs can be combined for greater storage capacity if redundancy is not a priority.

3. Optimized Virtual Machines and Container Performance

Virtual Machine Manager and Docker benefit significantly from SSD caching, providing faster loading times and smoother operation. This setup is especially useful for users who rely on VMs or containers for application development or complex data processing tasks.

4. Efficient Multimedia Streaming and File Management

SSD caching greatly improves multimedia streaming quality by reducing buffering times and allows faster handling of large files, which is advantageous for media-centric environments.

5. Faster Backup and Restoration

By reducing read/write times, SSD caching speeds up backup and restoration processes, enhancing overall data management efficiency.

Adding two equal-sized Synology SNV3400 SSDs transforms the DS723+ into a high-performance storage solution capable of handling intensive tasks while offering flexibility to scale with future needs. This approach allows users to select configurations that best suit their demands, whether through SSD caching, data redundancy, or additional high-speed storage.

Conclusion

In conclusion, upgrading both memory and cache in the Synology DS723+ provides a versatile means of maximizing system performance and efficiency, making it an ideal solution for users with demanding storage and data access needs.

Written on November 5th, 2024

File System

Understanding Disks, Storage Pools, and Volumes in NAS Systems

A Network Attached Storage (NAS) system employs a hierarchical structure comprising disks, storage pools, and volumes to efficiently manage and safeguard data. Comprehending these components is essential for optimizing storage solutions and ensuring data integrity.

(A) Disks

Disks refer to the physical hard drives or solid-state drives (SSDs) installed within the NAS device. They provide the raw storage capacity necessary for data storage.

Disks serve as the foundational hardware elements upon which storage pools and volumes are constructed. The number and type of disks determine the overall storage capacity and potential performance of the NAS.

(B) Storage Pools

A storage pool is a logical grouping of one or more disks combined to create a substantial storage space. It abstracts the physical disks into a manageable entity.

• Data Protection: Storage pools facilitate the implementation of RAID (Redundant Array of Independent Disks) configurations, offering data redundancy and fault tolerance.

• Flexibility: They enable efficient management and expansion of storage resources by grouping disks together.

(C) Volumes

A volume is a logical partition within a storage pool, formatted with a file system where data such as shared folders, applications, and system files are stored.

• Organization: Volumes aid in data organization by segregating different types of data or applications.

• Management: They allow for setting quotas, permissions, and enabling features like snapshots and data deduplication.

Artificial Scenario: Creating Multiple Storage Pools with Different Disk Sizes

Initial Setup:

• Disks: 2 x 12 TB disks.
• Storage Pool 1:
  • Configured in RAID 1 with the 2 x 12 TB disks.
  • Volume(s): Created for critical data requiring high redundancy.

Adding New Disks:

• Added Disks: 3 x 16 TB disks.
• Storage Pool 2:
  • Configured in RAID 5 with the 3 x 16 TB disks.
  • Volume(s): Multiple volumes created for different purposes, such as media storage, backups, or less critical data.

Benefits:

• Segmentation: Separation of data based on importance and access requirements.

• Optimization: Utilization of larger disks for data benefiting from increased capacity.

• Flexibility: Different RAID levels tailored to specific needs.

Written on November 2nd, 2024

Configuring Synology NAS for Internal-Only Access to Home and Homes Directories While Allowing Selective External Access

The home and homes directories on Synology NAS are intended as user-specific storage, separate from general shared folders. Designed primarily for internal use, these directories are restricted from external access by default, ensuring secure storage for individual data within the NAS. Meanwhile, access to other shared folders, such as nGeneNAS_Shared, can be selectively enabled for external connections. This guide provides a comprehensive approach to configure permissions, verify internal access, and allow external access only for specific shared folders.

Step 1: Enabling User Home Service for Internal Access

To ensure that each user’s home directory is accessible within the homes directory in File Station, the User Home service must be enabled. This service restores internal visibility of home directories following a system reset or configuration change:

Activate User Home Service

• Go to Control Panel > User & Group.
• Select Advanced on the sidebar.
• Check Enable user home service and click Apply. This creates the home and homes directories if they were previously disabled, enabling access for authorized users in File Station.

Step 2: Configuring Permissions for Internal-Only Access

Permissions need to be configured carefully to maintain internal access for authorized users while restricting external access to homes.

Setting Permissions for Guest and External Users

• Open Control Panel > Shared Folder and select homes.
• Click Edit and navigate to the Permissions tab.
• For Guest and any users designated for external access, set No Access. This ensures that external users cannot view or modify any contents within homes.

Assigning Permissions for Internal Users and Administrators

Ensure that internal users and administrators, including Frank, retain Read/Write access to the homes folder. This configuration allows each user to access their personal home directories while securing the homes directory from any external visibility or modifications.

In this setup, Guest and external users will be blocked from accessing homes as a whole, while internal users will retain access to their respective home directories within homes.

Step 3: Configuring External Access for Specific Shared Folders

To allow external access to nGeneNAS_Shared (or other shared folders designated for remote use), permissions and access controls can be configured separately:

Setting Permissions for External Access

• Go to Control Panel > Shared Folder and select nGeneNAS_Shared.
• Adjust permissions to grant external access only to trusted users or specific IP addresses. This approach allows selected shared folders to be accessible remotely, without compromising the security of the homes directory.

Step 4: Reinforcing External Access Restrictions

Additional security settings can further prevent unauthorized access to home and homes while allowing external access to designated shared folders:

Firewall Configuration

• Navigate to Control Panel > Security > Firewall.
• Set firewall rules to block external IPs from accessing home and homes, ensuring that these directories remain limited to internal access only. Configure exceptions as needed for shared folders intended for external access.

DSM Access Control Profile (DSM 7.0 and Above)

• For DSM 7.0 and later, go to Control Panel > Application Portal and create an access control profile.
• Configure the profile to restrict DSM access to LAN or trusted IPs, keeping home and homes inaccessible externally while selectively permitting access to other folders.

Limiting File Services for External Networks

• In Control Panel > File Services, disable any file-sharing protocols (e.g., SMB, AFP, NFS) not needed for external networks. This ensures that only the designated shared folders, such as nGeneNAS_Shared, are accessible remotely, while internal directories like homes remain protected.

VPN Configuration for Secure Remote Access (Optional)

If remote access to NAS is required for internal directories, consider enabling a VPN server. This setup allows trusted users to access NAS directories over an encrypted connection, keeping internal folders like home and homes secure without direct internet exposure.

Step 5: Confirming Internal-Only Visibility in File Station

Once these configurations are complete, verify that the home and homes directories are visible only within the internal network and inaccessible to external IPs. To ensure settings are correctly applied:

• Clear the browser cache, log out, and log back into File Station, or reboot the NAS if necessary. This refreshes permissions and visibility settings in File Station.

Written on November 2nd, 2024

Understanding the Distinction Between Admin and Frank Directories in Synology NAS’s Homes Directory

In Synology NAS, the homes directory serves as a centralized parent folder containing individual home directories for each user, including those with administrative privileges. When a user with administrative rights, such as Frank, is created, two specific directories within homes are noteworthy: the admin directory and the frank directory. Despite Frank’s administrative role, each directory has distinct purposes and access controls.

The Frank Directory: A Personal Home Folder for User-Specific Storage

Within the homes directory, the frank folder acts as a personalized home directory specifically for Frank. This folder is unique to Frank’s user account and is intended for storing his individual files, settings, and data. Access to this directory is restricted to Frank himself and any administrators authorized with the appropriate permissions, ensuring that Frank’s personal files remain secure and isolated from other users.

The Admin Directory: A Separate Home Folder for the Admin Account

The admin directory, also located within homes, is distinct from the frank directory. This folder serves as the home directory for the admin account, which is often created by default on Synology NAS systems. The admin folder is designated exclusively for the admin user account and holds data or settings specific to that account. Although Frank possesses administrative privileges, his personal data resides in his own frank directory, separate from the admin folder.

Key Distinction: Administrative Privileges vs. User-Specific Directories

This structure highlights the difference between having administrative rights and the organization of user-specific storage. Frank’s administrative privileges enable him to manage the NAS but do not alter the separation between his personal home directory (frank) and the system-created admin directory. This arrangement allows administrators to maintain individualized storage within their respective home directories while providing a secure and structured environment for data management on Synology NAS.

Written on November 2nd, 2024

External Access

Configuring External Access to Shared Folders on Synology NAS

A Synology Network Attached Storage (NAS) device facilitates the configuration of shared folders for external access. These shared folders serve as the primary means by which data is made available to users outside the local network. Files and directories not placed within these explicitly shared folders remain inaccessible to external Internet Protocol (IP) addresses, thereby enhancing the security of the system.

Understanding "home" and "homes" Directories

The Synology NAS features two distinct directories related to user data:

"homes" Directory: This directory acts as a centralized repository for individual users' personal folders. When the User Home Service is enabled, the "homes" directory is created. Within it, each user possesses a unique folder named after their username, ensuring the isolation of personal files.

"home" Directory: This refers to each user's personal folder within the "homes" directory. Upon logging in, users access their own "home" directory without visibility into other users' folders or the broader "homes" directory, thereby maintaining privacy.

An administrator account, such as "frank" with administrative privileges, has access to both the "home" and "homes" directories. This account can view and manage all user folders within "homes," while standard users can access only their individual "home" directories.

Making a User's Folder Accessible Externally

To provide external access to a specific user's folder (e.g., "frank"), it is advisable to create a separate shared folder rather than exposing the user's "home" directory directly. The following steps outline this process, substituting "FrankExternal" with nGeneNAS_Shared:

1. Create a New Shared Folder

• Navigate to the Control Panel, select Shared Folder, and click Create.
• Name the folder appropriately, such as nGeneNAS_Shared, and configure it as a new shared directory.

2. Set Folder Permissions

• Assign read and write permissions to the user "frank" for the new shared folder.
• Restrict permissions for other users unless additional access is required.

3. Enable External Access

• In the Control Panel, go to External Access.
• Configure remote access settings using methods such as QuickConnect, Dynamic DNS (DDNS), or port forwarding through the network router.
• Ensure that the new shared folder is included in the external access configuration.

4. Link or Copy Files

• Optionally, create a symbolic link (symlink) or manually copy files from "home/frank" to nGeneNAS_Shared.
• This approach allows external access to specific files without exposing the entire "homes" directory.

By following these steps, the nGeneNAS_Shared folder becomes accessible to external IP addresses, providing controlled and secure access to the user's data.

Behavior of Shared Folders Outside "home" and "homes"

Shared folders created outside of the "home" and "homes" directories operate independently of the User Home Service. These folders:

• Can be customized with specific permissions and access settings.
• Are not associated with any particular user's "home" directory.
• Can be configured for external access directly.
• Serve as versatile storage locations for general data, collaborative projects, or files intended for a broader audience.

Placing data intended for external access into these shared folders helps maintain the integrity and privacy of the "home" and "homes" directories.

Methods for External Access

Several methods are available for enabling external access to a Synology NAS. Below is a comprehensive comparison, with the methods presented as header columns and various attributes compared across them.

Security Considerations

• Shared Folder Access: Only files within explicitly shared folders are accessible externally. System directories, personal "home" folders, and other non-shared areas remain inaccessible unless specifically configured.
• Potential Vulnerabilities:
  • DDNS with Port Forwarding: Misconfiguration can expose NAS services. Open ports must be secured with strong authentication and up-to-date protocols.
  • WebDAV: Without proper HTTPS configuration and authentication, data may be vulnerable.

Access to Non-Shared Directories

Even if a security breach occurs via DDNS with port forwarding or WebDAV, typically only the files within shared folders are accessible. Directories such as "home," "homes," and system files remain protected unless explicitly shared. However, if an attacker gains administrative access, there is a risk of altered permissions and broader data exposure. Therefore, maintaining robust security practices is crucial.

Configuring "homes" or System Directories for Sharing

Sharing the "homes" or system directories is generally discouraged due to inherent security risks. If necessary, the following steps outline how to configure these directories securely, ensuring that the "homes" directory remains protected:

1. Enable User Home Service

• Access Control Panel > User > Advanced.
• Enable User Home Service to create the "homes" directory.
• This service ensures that each user has a personal "home" folder within the "homes" directory, maintaining privacy and isolation of user data.

2. Avoid Direct Sharing of "homes" Directory

• Refrain from directly sharing the "homes" directory via Control Panel > Shared Folder.
• Direct sharing can expose all user folders and sensitive system files to external access, increasing the risk of unauthorized access and data breaches.

3. Create Separate Shared Folders Outside "homes"

• For data intended for external access, create specific shared folders outside of the "homes" directory.
• Navigate to Control Panel > Shared Folder and create folders such as nGeneNAS_Shared.
• Assign appropriate permissions to these folders, ensuring that only intended users have access.

4. Implement Symbolic Links (Advanced Users)

• If access to specific data within the "homes" directory is necessary, consider creating symbolic links within the newly created shared folders.
• Use Secure Shell (SSH) to create symbolic links pointing to specific directories or files.
• Example Command:

  ln -s /volume1/homes/frank /volume1/nGeneNAS_Shared/frank_home

• Caution: Symbolic links can expose linked directories. Ensure that permissions are tightly controlled and that only trusted users have access to the shared folders containing symbolic links.

5. Restrict Permissions Strictly

• In the Control Panel, carefully manage permissions for shared folders.
• Grant read and write access only to necessary users.
• Utilize features such as Two-Factor Authentication (2FA) to enhance security for accounts with access to shared folders.

6. Regularly Monitor and Update Security Settings

• Keep the NAS firmware and applications up-to-date to protect against known vulnerabilities.
• Regularly review access logs and permissions to ensure that no unauthorized access is granted.
• Implement firewall rules and IP restrictions where applicable to limit access to trusted sources.

Recommendations

• Use Designated Shared Folders: For external access, create specific shared folders like nGeneNAS_Shared and manage permissions accordingly.
• Avoid Exposing Sensitive Directories: Do not share "home," "homes," or system directories unless absolutely necessary.
• Implement Strong Security Measures:
  • Use strong, unique passwords and enable two-factor authentication.
  • Keep the NAS firmware and applications updated.
  • Use HTTPS with valid SSL certificates.
  • Configure firewalls and access controls appropriately.

Written on November 1st, 2024

A Step-by-Step Guide to Identifying Unauthorized Login Attempts on Synology NAS

To monitor and identify possible unauthorized login attempts on a Synology NAS, several logs and settings are available for effective tracking and management. Synology NAS includes tools for monitoring suspicious activities such as failed login attempts and access from unauthorized IP addresses. The following step-by-step guide outlines methods to identify potential login hacking attempts and enhance security measures.

1. Enable and Review Security Logs

• Navigate to Control Panel > Log Center. (Install Log Center, if not available.)
• Under Log Center, go to Log > System and examine the logs related to account activities.
• Pay particular attention to repetitive failed login attempts or login activities from unexpected IP addresses.

Within the Security section, review entries for Failed Login and Account Lockout events. Multiple failed login attempts may suggest a brute-force attack, necessitating further investigation.

2. Utilize Security Advisor

• Open Security Advisor from the Control Panel to perform a comprehensive system scan.
• This scan can detect unusual login activities, configuration vulnerabilities, or other security issues.
• Based on its findings, Security Advisor may suggest adjustments to strengthen the NAS’s security posture.

3. Inspect Connection Logs

Within Control Panel, go to Log Center > Connection to check for connection-related activities.

Examine this log for multiple failed login attempts from specific IP addresses, and observe the time-stamped entries for any signs of abnormal access patterns.

4. Enable Account Protection via Auto Block

• Go to Control Panel > Security > Account and enable the Auto Block feature to prevent brute-force attacks.
• This feature temporarily blocks IP addresses that exceed a certain number of failed login attempts within a defined period.
• Configure the threshold for failed attempts and blocking duration according to security needs, and add known, trusted IP addresses to the allowlist to prevent accidental blocking.

5. Review Access from External Sources

If remote access is enabled, inspect the External Access logs to verify that only authorized IP addresses are accessing the NAS.

To further secure the NAS, consider restricting external access to trusted IP addresses only or disabling it entirely if not necessary.

6. Set Up Notifications for Suspicious Activity

• Under Control Panel > Notification, configure email or SMS notifications for real-time alerts on suspicious activities.
• Enable alerts for significant events, such as failed login attempts, to promptly receive notifications and address potential threats as they arise.

7. Advanced Option: Monitoring SSH Logins

For systems where SSH access is enabled, additional monitoring can be performed by logging in via SSH with an admin account and inspecting the system’s log files.

Within the /var/log directory, examine files like auth.log for any SSH login attempts from unauthorized IP addresses. This advanced measure helps in identifying potential security breaches through SSH.

Written on November 5th, 2024

DDNS

Configuring Synology NAS for Secure Remote Access with DDNS, Port Forwarding, SSL, and Local Access Control

This guide provides a structured approach to setting up Synology NAS for secure remote access, covering Dynamic Domain Name System (DDNS) setup, port forwarding, SSL certificate installation, and account access control. These steps ensure remote accessibility while protecting sensitive data and limiting specific account access to local networks only.

Essential Port Numbers for Synology NAS Configuration

To enable secure functionality, specific port numbers must be configured on the router for different NAS services. The table below details the necessary ports:

It is advisable to enable only the necessary ports and prioritize HTTPS (port 5001) to protect data in transit.

Setting Up DDNS on Synology NAS

Configuring DDNS for the NAS allows for a consistent hostname that bypasses issues with changing public IP addresses.

1. Access DSM: Navigate to Control Panel > External Access > DDNS.
2. Create a DDNS Entry: Select Add, choose a DDNS provider (Synology offers a free service), and enter a hostname (e.g., yournasname.synology.me).
3. Save the Settings: Apply the settings, allowing remote access to the NAS through the hostname, for instance, https://yournasname.synology.me:5001.

Ensuring Correct Port Forwarding and SSL Signing

After forwarding the 5000–6000 port range to the NAS’s internal IP, verify the connection by accessing https://yournasname.synology.me:5001. To further secure this connection, it is recommended to configure an SSL certificate.

SSL Certificate Signing for Synology NAS

To enable a verified SSL connection, install an SSL certificate as follows:

1. Access Control Panel: Go to Control Panel > Security > Certificate.
2. Add a Certificate: Select Add, then choose Get a certificate from Let's Encrypt (or another trusted provider).
3. Enter Certificate Details: Provide the DDNS hostname (e.g., yournasname.synology.me) and email for notifications. Synology will automatically request and install the SSL certificate.
4. Apply HTTPS Settings: After installation, redirect all HTTP connections to HTTPS:
   • Go to Control Panel > Network > DSM Settings.
   • Enable Automatically redirect HTTP connections to HTTPS to ensure a secure connection.

Steps to Disable External Access for Specific Accounts

To further secure the NAS, disable external access for specific accounts (e.g., admin and frank) while allowing local access only.

1. Log in to DSM: Access DSM on the NAS through a local network connection.
2. Navigate to Security Settings: Open Control Panel > Security > Account.
3. Configure IP Access Rules: Under Login Protection or Account Protection (depending on DSM version), create an Access Control Profile:
   • Select Create or Add and enter the IP range for the local network (e.g., 192.168.1.0/24).
   • Apply this profile to restrict external access for specific accounts, such as admin and frank.
   • Confirm and save the profile.
4. Disable Default Admin for External Access:
   • Go to Control Panel > User and select the admin account.
   • Under Edit, select Allow login only from trusted devices and specify the local network range as trusted.
   • Alternatively, disable the admin account entirely if another administrator account is available for local access (recommended best practice).
5. Firewall Configuration (Optional): Configure the NAS firewall to block all external IP addresses from reaching ports 5000 and 5001 for the admin and frank accounts, while allowing the local network range.
6. Test Access Restrictions:
   • From outside the local network, verify that access to the admin and frank accounts is blocked.
   • Confirm that local network access remains active by attempting login from a local device.

Finalizing and Testing Remote Access

With DDNS and SSL configured, and account restrictions in place, remote access to the Synology NAS is now securely available via https://yournasname.synology.me:5001. Regular monitoring of DDNS status, firewall settings, and DSM access logs (found under Control Panel > Security > Security Advisor) is recommended to maintain security and connectivity.

Written on November 3rd, 2024

Using an SSL Certificate for Secure Access to Synology NAS: Reusing Across DDNS and HTTPS Services

To ensure secure access to Synology NAS, a single SSL certificate can be configured to cover both DDNS and web-based HTTPS services. Reusing an SSL certificate across multiple services is achievable with attention to several key requirements, enhancing security and ensuring a seamless experience for users accessing the NAS via HTTPS.

Key Considerations for SSL Certificate Reuse

Domain Name Consistency

The SSL certificate must match the exact domain name used for both DDNS and web-based HTTPS access. For example, if meta-ngene.org is the primary domain, the SSL certificate should be issued specifically for meta-ngene.org. This will ensure compatibility and trustworthiness across all services that utilize this domain. Using myusername.synology.me would require a separate certificate if this domain is also actively used.

Certificate Type and Authority

A standard SSL certificate issued by a reputable Certificate Authority (CA), such as Let’s Encrypt, can typically be reused across services. Certificates issued by Synology’s free Let’s Encrypt integration are suitable for this purpose, as long as they cover the intended domain name. Self-signed certificates may also work but can result in browser security warnings, especially for external access.

Trusted CA for Compatibility

To avoid compatibility issues, it is recommended to use an SSL certificate from a trusted CA. Let’s Encrypt is widely supported, and Synology NAS makes obtaining and renewing certificates straightforward. This ensures that users can access the NAS without security warnings across various platforms.

Steps to Reuse an SSL Certificate for HTTPS on Synology NAS

Step 1: Obtain or Install the SSL Certificate for meta-ngene.org

• If an SSL certificate for meta-ngene.org is already active on Synology NAS for DDNS, confirm that it is properly matched to this domain.
• To obtain a certificate, navigate to Control Panel > Security > Certificate:
  • From here, request a new certificate from Let’s Encrypt or import an existing certificate if purchased from a third-party CA. Ensure it is explicitly issued for meta-ngene.org.

Step 2: Configure Services to Use the SSL Certificate

• Under Control Panel > Security > Certificate, go to Configure and assign meta-ngene.org as the SSL certificate for both DDNS and HTTPS web services (such as Web Station).
• Select meta-ngene.org from the dropdown menu for each relevant service.
• Apply these settings to ensure the SSL certificate is active for all services associated with meta-ngene.org.

Step 3: Update Network Settings if Replacing myusername.synology.me with meta-ngene.org

• If meta-ngene.org is to replace myusername.synology.me for accessing Synology NAS, adjust the NAS’s network configuration to recognize meta-ngene.org as the primary domain.
• Confirm that meta-ngene.org is reflected in all external access settings, ensuring that the SSL certificate covers every service and access point required.

Step 4: Verify HTTPS Access via meta-ngene.org

• Test the secure connection by accessing the NAS via https://meta-ngene.org. Ensure that the SSL certificate is recognized without security warnings, verifying compatibility.
• Repeat this verification for any web-based service using meta-ngene.org to confirm the SSL certificate’s applicability.

By following these steps, meta-ngene.org can serve as the primary secure domain for Synology NAS, allowing the SSL certificate to be reused effectively across both DDNS and HTTPS web services. This configuration ensures secure, consistent access across all designated NAS services.

Written on November 5th, 2024

SSH

Setting Up SSH Key-Based Authentication on Synology NAS Using an Existing SSH Key

SSH key-based authentication offers a more secure and convenient alternative to traditional password-based logins. By using cryptographic keys, unauthorized access is significantly reduced, and managing access across multiple servers becomes more efficient. This document outlines the necessary steps to configure a Synology NAS for SSH key-based authentication using an existing SSH key.

Step 1: Enabling SSH Access on Synology NAS

1.1 Access Synology DSM

Log in to the Synology DiskStation Manager (DSM) using an administrative account.

1.2 Navigate to Terminal Settings

Go to Control Panel > Terminal & SNMP.

1.3 Enable SSH Service

• Under the Terminal tab, check the option Enable SSH service.
• Confirm or change the SSH port number (default is 22).
• Click Apply to save the settings.

Step 2: Preparing the Existing SSH Key

2.1 Locate the Public Key

The public key is typically located at ~/.ssh/id_rsa.pub on the local machine.

2.2 Display the Public Key

Use the following command to display the public key:

cat ~/.ssh/id_rsa.pub

Copy the entire output, including the ssh-rsa prefix and any key comments.

Step 3: Copying the SSH Public Key to Synology NAS

Step3.1: Using ssh-copy-id Command

Note: This method assumes that the ssh-copy-id utility is available on the local machine.

3.1.1 Install ssh-copy-id (If Necessary)

• For Debian/Ubuntu Systems:

  sudo apt-get install ssh-copy-id

• For macOS with Homebrew:

  brew install ssh-copy-id

3.1.2 Execute ssh-copy-id

Run the following command, replacing username and nas_ip_address with the appropriate values:

ssh-copy-id -i ~/.ssh/id_rsa.pub username@nas_ip_address

Enter the password for the NAS account when prompted. This command appends the public key to the authorized_keys file on the NAS.

Step3.2: Manual Copying of Public Key

If ssh-copy-id is unavailable, the public key can be copied manually.

3.2.1 Access the NAS via SSH

Log in to the NAS using SSH with the existing username and password:

ssh username@nas_ip_address

3.2.2 Create the .ssh Directory

Ensure you are in the home directory and create the .ssh directory if it does not exist:

cd ~
mkdir -p .ssh
chmod 700 .ssh

3.2.3 Add the Public Key to authorized_keys

Open or create the authorized_keys file and paste the copied public key:

nano .ssh/authorized_keys

After pasting the key, save and exit the editor. Then, set the appropriate permissions:

chmod 600 .ssh/authorized_keys

Step 4: Testing SSH Key-Based Authentication

4.1 Log Out of the NAS

Exit the current SSH session:

exit

4.2 Attempt SSH Login with Key Authentication

Attempt to log in again using SSH. If configured correctly, access should be granted without prompting for a password:

ssh username@nas_ip_address

If access is successful without a password prompt, SSH key-based authentication is properly configured.

Step 5: Configuring Synology NAS for Enhanced SSH Security

5.1 Verify SSH Configuration File (Optional)

The SSH daemon configuration file is located at /etc/ssh/sshd_config on the NAS. Adjusting settings in this file can further enhance security.

5.2 Disable Password Authentication (Optional)

To prevent password-based logins and enforce key-based authentication, modify the SSH configuration as follows:

5.2.1 Open the SSH Configuration File

sudo vi /etc/ssh/sshd_config

5.2.2 Modify Authentication Settings

Locate the line containing PasswordAuthentication and set it to no:

PasswordAuthentication no

5.2.3 Save and Exit

After making the changes, save and exit the editor.

5.3 Restart SSH Service

Apply the configuration changes by restarting the SSH service:

sudo synoservice --restart sshd

Warning: Disabling password authentication will prevent login using passwords. Ensure that SSH key authentication is functioning correctly before implementing this change.

References

• Synology Official Documentation
• SSH Key Management Best Practices

- Written on November 4th, 2024 -

Secure SSH Access, Shared Folder Management, and Disabling Password-Based Login on Synology NAS

Synology NAS offers SSH-based access for file management, security configurations, and software installation, including advanced customizations not accessible through the DSM interface alone. Below is a comprehensive guide detailing SSH navigation, secure login settings, and Emacs installation on a Synology NAS.

Accessing Shared Folders on Synology NAS via SSH

To manage shared folders through SSH, begin by navigating to the directory where Synology NAS typically mounts shared folders. On Synology systems, these shared folders are located under /volume1 by default, although configurations may vary depending on the system setup.

1. Log in to the NAS via SSH

ssh frank@nas_ip_address

2. Navigate to the Shared Folder Directory

Move to the primary volume directory with:

cd /volume1

3. Access a Specific Shared Folder

To enter a specific shared folder, use:

cd /volume1/shared_folder_name

Within this directory, files and subdirectories can be accessed and managed according to the permissions granted to the frank account.

Disabling Password-Based SSH Authentication on Synology NAS

For added security, it is advisable to disable password-based SSH authentication, allowing only key-based access. This procedure involves editing the SSH configuration file to permit only SSH key login. Access to the SSH configuration file is required to implement this change.

1. Log in to the NAS via SSH with an SSH Key

ssh frank@nas_ip_address

2. Edit the SSH Configuration File

Access the SSH daemon configuration file:

sudo vi /etc/ssh/sshd_config

3. Disable Password Authentication

Locate the line:

#PasswordAuthentication yes

Remove the # if present and change yes to no:

PasswordAuthentication no

4. Save and Exit the File

In vi, press Esc, type :wq, and press Enter to save and close.

5. Restart SSH Service

Apply the new settings by restarting SSH:

sudo synosystemctl restart sshd.service

If synosystemctl is not supported on the current DSM version, consider rebooting the NAS:

sudo reboot

- Written on November 4th, 2024 -

Network Separation

Integrated Deployment for Synology DS723+ and DS423+

1. Introduction

Synology NAS devices provide versatile, scalable solutions for data storage, backup, and a wide array of network services. Among these, the DS723+ and the DS423+ stand out as robust and complementary models capable of forming an adaptable and secure multi-NAS ecosystem. This document merges key insights from multiple discussions to deliver:

• A two-NAS architecture focusing on a DS723+ (with external connectivity) and a DS423+ (secured in an internal environment).
• Network separation to enhance security by preventing unauthorized access to critical data.
• RAID configurations and expansions, including initial RAID setups (RAID 1) and subsequent transitions (e.g., RAID 5).
• Hot-swapping processes and guidelines on when to power down.
• Performance improvements through memory (RAM) and SSD cache upgrades.
• Security considerations for internet-exposed deployments, including best practices for authentication, firewall settings, and backups.

This integrated reference aims to minimize omissions of important ideas while refining and organizing content for professional publication.

2. Overview of the DS723+ and DS423+

1. Synology DS723+

   • Compact 2-Bay NAS: Tailored for higher-performance tasks in environments where physical footprint is limited.
   • Enhanced Processing and Memory Ceiling: Supports up to 32 GB RAM and NVMe SSD caching, beneficial for virtualization (Virtual Machine Manager), Docker containers, and active file sharing.
   • Ideal Use Cases: Hosting containers, web services, external file sharing, and collaboration platforms.

2. Synology DS423+

   • 4-Bay NAS with Larger Capacity: Accommodates up to four HDDs, providing ample storage for shared folders, backups, and archival data.
   • RAID Flexibility: Natively supports RAID 5, RAID 6, or Synology Hybrid RAID (SHR) with single- or dual-disk fault tolerance.
   • Recommended Use Cases: Central backup repository, high-capacity file server, or local-only data storage with no external exposure.

Key Synergy: When combined, the DS723+ can serve as the performance-driven primary node for daily operations (including internet-facing access), while the DS423+ offers large, redundant storage with minimal exposure to external threats.

3. Network Separation and Security

1. Rationale for Using Two Separate NAS Units

   • Security Through Isolation
     • Placing the DS423+ entirely on an internal network (with distinct IP ranges and no public port forwarding) greatly reduces the risk of external intrusion.
     • The DS723+ manages external-facing services, protected by firewall rules, VPN configurations, or QuickConnect, ensuring more controlled exposure.
   • Flexibility and Redundancy
     • Each NAS operates on a separate DSM instance with dedicated resources.
     • A security incident or malfunction on the DS723+ is less likely to affect the DS423+, preserving critical data integrity.
   • Comparison with Direct Expansion
     • Synology’s DX517 is an expansion unit for certain models, attaching via eSATA and extending the primary NAS’s storage pool.
     • A DS423+, however, remains fully independent, benefiting from its own CPU, memory, and DSM environment. This approach can be more expensive but confers stronger fault isolation and simplifies disaster recovery scenarios.

2. Security Measures for External Access

   • Avoid Direct Port Forwarding: Use Synology QuickConnect or a VPN server (OpenVPN, WireGuard, etc.) to encrypt remote sessions.
   • Multi-Factor Authentication (MFA): Enforce two-factor authentication for administrative or user logins.
   • Disable Default Admin Account: Rename or remove the default admin account and enforce strong password policies.
   • Regular Updates: Keep DSM, packages, and antivirus tools updated, and run Security Advisor to detect potential vulnerabilities.
   • Firewall and Geofencing: Restrict inbound traffic to known IP ranges to limit brute-force attacks.

4. RAID Configurations and Expansions

Synology NAS supports multiple RAID types, each balancing performance, redundancy, and capacity. The following table summarizes frequently used RAID levels with example capacities using 12 TB HDDs:

• RAID 1 (2 × 12 TB)
  • Total of ~12 TB usable with 1-disk fault tolerance.
  • Recommended for smaller environments with higher redundancy needs.
• RAID 5 (3–4 disks)
  • Balances capacity, performance, and 1-disk fault tolerance.
  • For instance, 3 × 12 TB = ~24 TB usable; 4 × 12 TB = ~36 TB usable.
• RAID 6 or RAID 10
  • More advanced redundancy (2-disk fault tolerance in RAID 6 or improved performance in RAID 10).
• Synology Hybrid RAID (SHR)
  • Automatically optimizes capacity when mixing different drive sizes.
  • Can be configured for single- or dual-disk redundancy.

5. Example Deployment and RAID Migration

1. DS723+: External-Facing NAS

   • Recommended RAID: RAID 1 with 2 × 12 TB drives for fault tolerance.
   • Rationale: Maintains availability even if one disk fails, critical for externally accessible services.
   • Performance Upgrades (Optional):
     • RAM Expansion: Up to 32 GB for running multiple Docker containers, Virtual Machine Manager, or concurrent file-sharing sessions.
     • NVMe SSD Cache: Significant improvement for random reads/writes (e.g., databases, log-intensive services).

2. DS423+: Internal-Only NAS

   • Initial RAID Setup: 2 × 12 TB in RAID 1 to learn basic Synology operations.
   • Subsequent RAID Migration: Add a third 12 TB disk, hot-insert while powered on, and migrate RAID 1 → RAID 5 (Storage Manager → Storage Pool → Action → Change RAID Type).
   • Final Capacity: Approximately 24 TB usable (3 × 12 TB in RAID 5).
   • Primary Function: Secured data repository and backup location with no external exposure.

3. Hot-Swapping vs. Powering Down

   • Hot-Swap: Recommended for adding or replacing disks in RAID 1, 5, 6, or 10 arrays that provide fault tolerance.
   • Power Down: Advised when removing the only disk of a single-disk volume, or when multiple disks require simultaneous removal.
   • Disk Wipe/Preparation: Before repurposing any HDD, consider securely erasing old partitions in DSM (Storage Manager → Wipe Disk) to avoid metadata conflicts.

6. Backup Strategy and Roles

1. DS423+ as a Dedicated Backup Repository

   • Centralized Backup: Consolidates backups from PCs, servers, or the DS723+ using Synology Hyper Backup, Snapshot Replication, or Active Backup for Business.
   • Redundancy: RAID 5 or RAID 6 ensures data remains available even if disks fail.
   • Long-Term Storage: Larger capacity (4 bays) provides room to scale for future growth.

2. DS723+ as the Primary NAS

   • Frequent Backup Schedules: Since RAID 1 (or RAID 0) can still fail under certain conditions, daily or weekly incremental backups to the DS423+ are prudent.
   • Offsite Copy: Consider replicating critical data to a cloud service (e.g., Synology C2) for disaster recovery.

7. Performance Enhancements for NAS723+

Written on December 31, 2024

Removing Shared Folders and Enabling Private Directories on Synology NAS 423+ for Internal Network Separated from External IP Access

This guide provides comprehensive instructions for removing shared folders and enabling private directories on a Synology Network Attached Storage (NAS) device. Additionally, it includes steps to configure a recycle bin, ensuring data privacy and protection against accidental deletions.

Prerequisites

• Administrative Access: Ensure that administrative privileges are available to perform the operations.
• Data Backup: It is recommended to back up important data before proceeding with deletion or configuration changes.

Removing Shared Folders Using DSM Web Interface

The DiskStation Manager (DSM) offers a user-friendly web interface for managing shared folders.

Step 1: Log in to DSM

1. Open a Web Browser:
   • Launch your preferred web browser.
2. Access DSM Login Page:
   • Enter the IP address of the Synology NAS in the address bar.
3. Authenticate:
   • Enter the administrative credentials to log in.

Step 2: Access Control Panel

1. Navigate to Control Panel:
   • From the DSM desktop, click on the Control Panel icon to open the settings.

Step 3: Navigate to Shared Folder Settings

1. Select Shared Folder:
   • In the Control Panel, click on Shared Folder under the File Services or Privileges section.

Step 4: Select and Delete the Shared Folder

1. Locate the Shared Folder:
   • In the Shared Folder window, identify the folder intended for deletion from the list.
2. Select the Folder:
   • Click on the desired shared folder to highlight it.
3. Initiate Deletion:
   • Click the Remove button located at the top of the page.

Step 5: Confirm Deletion

1. Confirmation Dialog:
   • A dialog box will appear, asking for confirmation to delete the folder.
2. Proceed with Deletion:
   • Click Yes to confirm the deletion.
3. Data Deletion Option:
   • If prompted, choose whether to permanently delete the associated data. Caution: This action is irreversible.

Enabling and Utilizing Private Directories

Transitioning to private directories enhances data privacy by restricting access to individual users. The following steps outline the process to enable private directories for the admin account and configure a recycle bin.

Step 1: Enable the Home Folder Feature

1. Log in to DSM:
   • Ensure that you are logged in with administrative credentials.
2. Access Control Panel:
   • Click on the Control Panel icon from the DSM desktop.
3. Enable User Home Service:
   • Navigate to User & Group > Advanced Settings.
   • In the User Home section, check the box labeled Enable user home service.
   • Click Apply to save the changes.
   • This action creates a private "home" directory for each user on the NAS.

Step 2: Access the Private Directory

1. Log in as the Admin User:
   • Ensure the admin account is active and has appropriate permissions.
2. Open File Station:
   • From the DSM desktop, launch the File Station application.
3. Navigate to Home Directory:
   • In File Station, click on the home directory to access the private space.
   • The admin can securely store files here, with access restricted to the admin account.

Step 3: Prevent Creation of Additional Shared Folders

To avoid creating unnecessary shared folders:

1. Review Shared Folder Settings:
   • Navigate to Control Panel > Shared Folder.
2. Delete Unnecessary Shared Folders:
   • Follow the steps outlined in the "Removing Shared Folders Using DSM Web Interface" section to delete any shared folders that are not required.
3. Restrict Shared Folder Creation:
   • Ensure that user permissions do not allow the creation of new shared folders unless necessary.

Step 4: Enable and Configure Recycle Bin

Setting up a recycle bin ensures that deleted files can be recovered in case of accidental deletion.

1. Access Shared Folder Settings:
   • Navigate to Control Panel > Shared Folder.
2. Edit Shared Folder Properties:
   • Select the home shared folder from the list.
   • Click the Edit button.
3. Enable Recycle Bin:
   • In the Edit Shared Folder dialog, locate and check the box labeled Enable Recycle Bin.
4. Configure Recycle Bin Settings:
   • Set desired parameters such as retention period for deleted files.
5. Apply Settings:
   • Click OK to save and apply the settings.
6. Verify Recycle Bin Functionality:
   • Test the recycle bin by deleting a test file within the private directory.
   • Ensure that the file is moved to the recycle bin and can be restored if necessary.

Written on January 3, 2025

Miscellaneous

Safely Shutting Down Synology NAS to Ensure Data Integrity

To safely shut down a Synology NAS and protect data integrity, the following steps may be observed. A careful shutdown process ensures that all ongoing tasks and connections are properly terminated, minimizing the risk of data corruption.

Step 1: Close Active Applications and Processes

• Ensure that any active applications, file transfers, or scheduled tasks are completed or paused before proceeding. This step prevents data corruption by stopping ongoing activities prior to powering down.

Step 2: Disconnect Remote Connections

• Notify any remote users about the planned shutdown to avoid disruptions.
• Disconnect active remote sessions or connections to ensure that no user remains connected to the NAS.

Step 3: Perform a Graceful Shutdown via DSM Interface

• Access the DiskStation Manager (DSM) interface.
• Navigate to Main Menu > Shutdown.
• Select Shut Down and confirm the action. This approach allows the NAS to close all processes in an orderly manner, safeguarding data integrity.

Step 4: Use the Power Button if DSM Is Unavailable

• When DSM access is unavailable, press and hold the Power button on the NAS for approximately 3–5 seconds. This initiates a safe shutdown sequence, though using the DSM interface is preferable.

Step 5: Wait for Status Lights to Turn Off

• Allow the NAS adequate time to complete the shutdown. Wait until the status and disk activity lights have turned off, indicating that all processes have ceased and the drives have stopped.

Step 6: Optional: Unplug the NAS

• If the NAS is to remain off for an extended duration, unplugging it may prevent accidental power-on or electrical surges.

By following these steps, Synology NAS can be powered down safely, maintaining data integrity and reducing the risk of data loss or corruption.

Written on November 5th, 2024

Extending Session Timeout for Synology DSM Access

To address connection timeouts and ensure extended access to Synology DSM, adjustments can be made to the session timeout settings within the DiskStation Manager (DSM). This modification can enhance user experience by preventing unintended logouts due to inactivity. A step-by-step guide is provided below to assist in adjusting these settings in a precise and accessible manner.

Step 1: Access the DSM Control Panel

Begin by opening a web browser and entering the IP address of the Synology NAS (e.g., http://192.168.1.100). Proceed to log in using the appropriate credentials to access the DSM dashboard.

Step 2: Locate Security Settings

Within the DSM interface, navigate to the Control Panel. From the options available, select "Security" to access relevant configurations.

Step 3: Adjust the Login Timeout Setting

Within the Security section, open the "Login" tab (also known as Login Settings in some DSM versions). Here, find the "Logout Timer" option, which determines the duration of the session without interaction before automatic logout occurs.

Step 4: Set Desired Session Duration

Modify the timer to the preferred duration to ensure a stable and extended session. After selecting the new duration, click "Apply" to save the adjustments.

By following these steps to configure the Logout Timer within Security > Login Settings, DSM access can be maintained for an extended period without interruptions from auto-logout. This setting provides flexibility to meet varying access needs and ensures that workflow disruptions are minimized.

Written in November 6th, 2024

Understanding and Securing Synology NAS Activity During Off-Peak Hours

Concerns may arise when a Synology Network Attached Storage (NAS) device exhibits activity during periods of expected inactivity, such as the middle of the night. This document explores potential reasons for such behavior and addresses the possibility of remote access by Synology through its software, despite router configurations that restrict external access. Comprehensive steps for diagnosing and securing the NAS are also provided to ensure optimal performance and security.

Potential Reasons for NAS Activity During Off-Peak Hours

1. Scheduled Tasks and Maintenance

• Automatic Backups: Backup operations, utilizing applications like Hyper Backup or Active Backup, are often scheduled during off-peak hours to minimize disruption. These tasks require the NAS to be active to execute the backup processes.
• System and Package Updates: The NAS may automatically download and install system firmware updates or updates for installed packages (e.g., surveillance systems, media servers). This ensures that the device operates with the latest features and security patches.
• Disk Scrubbing and Health Checks: Regular maintenance tasks, such as disk scrubbing and SMART tests, are performed to maintain drive health and data integrity. These processes are typically scheduled during periods of low activity.

2. Indexing and Media Services

• File Indexing: To enhance search performance, the NAS indexes stored files. This process can be resource-intensive and is often conducted during times of minimal usage.
• Media Scanning: Media services, such as Video Station or Audio Station, may scan for new media files to update libraries. This scanning process can activate the NAS to process and organize media content.

3. Antivirus and Security Scans

• Antivirus applications installed on the NAS, such as Synology Antivirus Essential, may perform routine scans to detect and mitigate potential threats. These scans are typically scheduled during off-hours to reduce impact on system performance.

4. Active Services and Applications

• Cloud Synchronization: Services like Synology Drive or Cloud Sync may synchronize data with cloud services during off-peak hours, necessitating NAS activity.
• Surveillance Station: Continuous recording or processing of video footage by Surveillance Station can keep the NAS active throughout the night.

5. Network Activity from Internal Devices

Even with external access restrictions, devices within the local network—such as computers, smartphones, or smart TVs—may access the NAS for various services, leading to unexpected activity.

6. Hardware and Environmental Factors

• Hardware Issues: Malfunctions in hardware components, such as fans, can cause the NAS to operate continuously, resulting in persistent noise.
• Power Settings: Configurations that allow the NAS to wake from sleep or hibernation modes for maintenance tasks can lead to nighttime activity.

Assessing Remote Access Capabilities

Despite router configurations that prevent external IP access, understanding the mechanisms through which remote access is facilitated is crucial for ensuring NAS security.

Synology's Remote Access Mechanisms

• QuickConnect: This feature allows remote access without the need for port forwarding by establishing an outbound connection to Synology’s servers. Access is controlled through QuickConnect IDs and user credentials, ensuring that only authorized users can connect. Synology itself does not have access to the data; it merely facilitates the connection.
• Synology DDNS (Dynamic DNS): This service provides a domain name that maps to the NAS’s dynamic external IP address. When combined with port forwarding, it allows access via the provided domain name. Access control is maintained through user credentials and network configurations.

Synology’s Access to the NAS

By default, Synology does not access the NAS remotely. Remote access features require explicit user configuration and consent. Synology adheres to strict privacy policies, ensuring that user data remains inaccessible without authorization. Assistance from Synology Support for remote access necessitates user initiation and consent, typically involving temporary access under user supervision.

Securing the NAS Against Unintended Access

To ensure the NAS remains secure and operates as intended, the following measures are recommended:

Review and Manage Remote Access Settings

• Disable QuickConnect: If not in use, QuickConnect should be disabled to prevent unsolicited remote connections.
• Manage DDNS and Port Forwarding: Ensure that no unintended DDNS services are active and that port forwarding rules are correctly configured to block external access.

Configure Firewall and Security Settings

• Firewall Configuration: Utilize the built-in firewall to restrict access to trusted IP addresses and block unauthorized traffic.
• Enable Security Features: Activate features such as Auto Block to prevent brute-force attacks and regularly run Security Advisor to identify and mitigate vulnerabilities.

Disable Unused Services

Minimizing the number of active services reduces potential entry points for unauthorized access. Services like SSH, Telnet, or unnecessary web services should be disabled if not required.

Regular Updates and Maintenance

Keeping the NAS’s DiskStation Manager (DSM) and all installed packages up to date ensures that the latest security patches and features are applied, safeguarding against known vulnerabilities.

Monitoring and Diagnostics

Regular monitoring of the NAS’s activity can help identify and address unexpected behavior:

• Log Center: Regularly review logs to monitor access attempts, system events, and other activities for any suspicious behavior.
• Resource Monitor: Utilize Resource Monitor to observe real-time CPU, memory, disk, and network usage, aiding in the identification of active processes.

Enhancing Physical and Network Security

• Network Segmentation: Placing the NAS on a separate VLAN or subnet can further restrict access and enhance security.
• Strong Authentication: Implementing strong, unique passwords and enabling Two-Factor Authentication (2FA) adds additional layers of security to NAS user accounts.

Written on November 30th, 2024