SSH – Warning: remote host identification has changed

When using ssh, if you get the following message, do not panic. Chances are nothing nasty has happened.

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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 the RSA host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
e2:7c:58:33:c5:c7:ce:75:a9:55:1a:ef:ef:d7:4b:fe.
Please contact your system administrator.
Add correct host key in /home/someone/.ssh/known_hosts to get rid of this message.
Offending key in /home/someone/.ssh/known_hosts:1
RSA host key for www.somesite.com has changed and you have requested strict checking.
Host key verification failed.

This means that the public key of the host has changed and the key stored in your cache is no longer valid. Simply do the following;

$ vi  .ssh/known_hosts

Inside this file, remove the line which refers to the host, e.g. somesite.com. Save the file and start ssh again. That’s it!