Solved: How do I fix “failed (Host key verification failed)” error occurs when testing FortiSIEM-FortiGate connectivity with SSH credentials?

Problem Description

This article describes how to fix an issue where SSH connectivity from FortiSIEM to FortiGate does not function.

Scope

Applies to FortiSIEM version 6.6.0 and any other versions that receive the ‘Host key verification failed’ error when testing SSH connectivity to a FortiGate device.

Solution

During an attempt to configure SSH on FortiGate, a ‘failed (Host key verification failed)’ error may occur while trying to test connectivity with the SSH credentials.

If this occurs, first check whether the following entry exists within the below directory in the supervisor:

/opt/phoenix/bin/.ssh/known_hosts

If so, delete the known_hosts file (or FortiGate entry in that file) to fix the issue. SSH credentials will then start functioning as normal when used to connect with the FortiGate.