Best Fixes
Confirm with the system owner or hosting platform that the host key really changed, then update the known_hosts entry safely.
If the host is new or rebuilt, remove the stale entry only after verifying the expected fingerprint.
Error Fix
How to Fix 'Host key verification failed' in SSH
What changed on the remote host and how to update trust safely without ignoring the warning.
This warning means the host key presented by the server does not match what your client previously trusted. Sometimes the host was legitimately rebuilt. Sometimes the warning matters for security.
Avoid This
Do not blindly disable host key checking just to make the warning disappear.
Do not remove trust records without validating whether the host change is legitimate.
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