Resolving ‘Host Key Verification Failed’ Error: A Comprehensive Guide

The SSH client fails to verify the authenticity of the remote host when connecting to it, resulting in a “Host key verification failed” or “Remote host identity changed” warning. The warning may seem serious, but it’s usually not related to an attack. It usually occurs when you change the operating system on your VPS or reinstall it.

a) Remove the entry from the known_hosts file

1. After connecting to your VPS via SSH, the host key will be added to the known_hosts file on your device. After an operating system change or reinstallation, this entry needs to be removed using the ssh-keygen -R [vps-ip] command on the terminal.

Notes: Replace [vps-ip] with your VPS IP to create a backup of the known_hosts file and delete the host key entry associated with your VPS IP.

b) Connect to the server

1. After removing the old entry, reconnect to your VPS using SSH and verify the host key for a smooth connection. If the issue persists, try the following steps:

• Ensure that you are connected to the correct IP address or hostname.
• Ensure that your firewall is not obstructing the connection.
• Restart your local device or VPS to reset network settings.