Quickly Remove a Known-Host Entry

I’ve had plenty of scenarios in development where I have updated a development machine and the credentials are updated causing SSH errors. This happens frequently in Vagrant as well. But it’s simple and quick to remove the old known signature.

When updating your known_hosts; make sure that you understand what you are doing. The known_hosts entries are there to protect you by cryptographically validating a server really is who they say they are. IE: Do Not Delete Things You Don’t Trust.

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@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
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IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that a host key has just been changed.
The fingerprint for the RSA key sent by the remote host is