Advanced SoftEther VPN: Performance Tuning and Monitoring Print

Hello there! I’m Corels from Emmanuel Corels Creatives. In today’s guide, we’re taking a deeper dive into optimizing your SoftEther VPN Server. Once you have your VPN up and running, ensuring it performs efficiently and remains stable under load is crucial. In this article, I’ll walk you through various techniques and commands for performance tuning and monitoring your SoftEther VPN Server. We’ll cover configuration tweaks, logging, and practical monitoring tips that you can apply whether you’re using Linux, Windows, or another supported platform.

Why Performance Tuning and Monitoring Matter

After deploying your VPN server, you want it to:

• Handle high traffic loads smoothly without excessive latency.
• Utilize system resources efficiently to avoid bottlenecks.
• Quickly diagnose issues when performance degrades or connectivity drops occur.
• Ensure that security measures don’t come at the cost of performance.

By fine-tuning settings and actively monitoring performance, you can keep your VPN running reliably and make informed decisions about scaling or adjusting configurations as your network grows.

Step 1: Monitoring System Resources

Begin by keeping an eye on your server’s hardware performance.

• Check CPU, Memory, and Uptime:

  /system resource print
  

  This command displays current CPU load, memory usage, uptime, and temperature. High CPU usage might indicate heavy encryption overhead, while low memory could signal a need for resource upgrades.

• Review System Logs:

  /log print
  

  Look for recurring warnings or error messages related to VPN connections, certificate expirations, or resource limits.

Step 2: Tuning Virtual Hub Settings

The Virtual Hub is the core of your SoftEther VPN Server. Optimizing its settings can improve performance:

• Adjust Session Timeouts and Maximum Connections: In the SoftEther VPN Server Manager or via vpncmd, review settings under your Virtual Hub’s configuration. For example, if you expect many short-lived sessions, consider reducing the session timeout to free up resources.

• Encryption and Compression: SoftEther supports multiple encryption algorithms and compression settings. While stronger encryption (like AES-256) offers better security, it might increase CPU load. If your server is under heavy load and you trust your network, you might balance security with performance by experimenting with slightly less demanding options.

  Use vpncmd to view or modify encryption settings as needed:

  Help OpenVpnEnable
  

  This command shows you the available options when enabling OpenVPN on your Virtual Hub. You can experiment with different ciphers and authentication methods.

Step 3: Using vpncmd for Real-Time Monitoring

The SoftEther command-line management tool, vpncmd, provides insights into VPN performance:

• Check Active Sessions:

  UserList
  

  This displays all active VPN sessions. If you notice sessions lingering or unexpected disconnects, it could be a sign to adjust your timeout settings.

• Review Hub Information:

  HubInfoGet
  

  This command shows details about your Virtual Hub, including uptime and current settings.

• Monitor Logs within vpncmd: Use the Log command to display recent events. This can help you spot issues like failed authentications or negotiation errors.

Step 4: External Monitoring Tools

For a more comprehensive view, integrate your SoftEther VPN Server with external monitoring systems:

• SNMP Integration: Configure SNMP on your VPN server so that tools like The Dude, PRTG, or Nagios can monitor system performance, bandwidth usage, and session counts. In SoftEther, this might involve enabling SNMP through your underlying OS (Linux or Windows) since SoftEther itself does not directly provide SNMP settings.

• The Dude: Use MikroTik’s The Dude for visual network monitoring. Add your VPN server as a device, and configure SNMP or ping-based monitoring to track performance metrics and receive alerts if something goes wrong.

• Custom Scripts: Write custom scripts using vpncmd or your OS’s scripting capabilities to periodically log performance metrics. For instance, you might create a script to log the number of active sessions and CPU usage, then email you a summary daily.

  Example (using Linux shell scripting):

  #!/bin/bash
  echo "VPN Server Resource Usage:" >> /var/log/vpn-monitor.log
  /system resource print >> /var/log/vpn-monitor.log
  echo "Active VPN Sessions:" >> /var/log/vpn-monitor.log
  sudo /usr/local/softether/vpncmd /SERVER localhost /PASSWORD:YourAdminPass "UserList" >> /var/log/vpn-monitor.log
  

  Schedule this script using cron to run at regular intervals.

Step 5: Adjusting Firewall Policies for Performance

Ensure that your firewall rules are optimized and not inadvertently slowing down your VPN traffic:

• Allow Essential VPN Ports: Confirm that rules allowing VPN traffic (such as TCP 443, 1194, or UDP ports 500/4500 for L2TP/IPsec) are prioritized in your firewall configuration.

  Example (for OpenVPN on port 1194):

  /ip firewall filter add chain=input protocol=tcp dst-port=1194 action=accept comment="Allow OpenVPN traffic"
  

• Limit Logging for High-Traffic Rules: Excessive logging can impact performance. Enable logging only on critical rules and disable logging on those that process high volumes of traffic.

Final Thoughts

Optimizing and monitoring your SoftEther VPN Server is an ongoing process that balances security, performance, and reliability. By regularly checking system resources, fine-tuning Virtual Hub settings, using vpncmd for real-time monitoring, and integrating external monitoring tools, you can ensure your VPN operates smoothly—even under heavy load.

Take the time to experiment with different configurations and monitor how each change affects your performance. As always, if you have any questions or need further guidance, feel free to reach out. Happy tuning, and here’s to a high-performance, secure VPN environment!

Explained with practical clarity by
Corels – Admin, Emmanuel Corels Creatives