Hetzner Network Unreachable

Hetzner Network Unreachable: Troubleshooting Guide

Experiencing "Hetzner Network Unreachable" errors can be frustrating. This guide provides practical steps to diagnose and potentially resolve connectivity issues with your Hetzner dedicated server or cloud instance. Remember to always back up critical data before making significant network changes.

Initial Checks and Diagnostics

Before diving into complex troubleshooting, perform these basic checks:

Check Hetzner Status Page: Visit Hetzner's status page (status.hetzner.com) to see if there are any known network outages or maintenance activities affecting your region. This is the quickest way to rule out a widespread issue.
Ping Your Server: Use the ping command from a different network (e.g., your home internet connection) to check if your server responds. If you can't ping it, the problem likely lies outside your server.
Traceroute: Perform a traceroute (traceroute on Linux/macOS, tracert on Windows) to identify where the connection is failing. This can help pinpoint if the issue is within Hetzner's network or further upstream.
Check Server Load: High CPU or memory usage can sometimes lead to network issues. Log into your server's console (if possible) and monitor resource utilization using tools like top or htop.

Advanced Troubleshooting Steps

If basic checks don't reveal the problem, investigate these areas:

Firewall Configuration: Ensure your firewall (e.g., iptables or ufw) isn't blocking essential traffic. Check rules for SSH (port 22), HTTP (port 80), and HTTPS (port 443), if applicable. A misconfigured firewall is a common cause.
Network Configuration Files: Verify your network configuration files (e.g., /etc/network/interfaces on Debian/Ubuntu, /etc/sysconfig/network-scripts/ifcfg-* on CentOS/RHEL) are correctly configured with the correct IP address, gateway, and DNS servers. Hetzner typically provides this information in your server's control panel.
DNS Resolution: Check if your server can resolve domain names. Use the nslookup or dig command to query DNS servers. Incorrect DNS settings can prevent your server from accessing external resources.
Contact Hetzner Support: If you've exhausted these troubleshooting steps and the problem persists, contact Hetzner support. Provide them with detailed information about the issue, including the steps you've already taken. Include traceroute results and any error messages you've encountered. Hetzner technicians can access server logs and perform network diagnostics that you may not be able to. Expect a response time of approximately 15-60 minutes.

By systematically working through these steps, you can often identify and resolve "Hetzner Network Unreachable" errors. Remember to document your troubleshooting process for future reference.