Upon attempting to login via ssh, PuTTY provides the following warning:
WARNING - POTENTIAL SECURITY BREACH!
The server’s host key does not match the one PuTTY has cached in the registry. (other explanatory text follows, as well as the new RSA2 key fingerprint offerred by the server)
From the PuTTY manual:
"10.2 ‘WARNING - POTENTIAL SECURITY BREACH!’
This message, followed by ‘The server’s host key does not match the one PuTTY has cached in the registry’, means that PuTTY has connected to the SSH server before, knows what its host key should be, but has found a different one.
This may mean that a malicious attacker has replaced your server with a different one, or has redirected your network connection to their own machine. On the other hand, it may simply mean that the administrator of your server has accidentally changed the key while upgrading the SSH software; this shouldn’t happen but it is unfortunately possible.
You should contact your server’s administrator and see whether they expect the host key to have changed. If so, verify the new host key in the same way as you would if it was new. "
Did Dreamhost change host key’s on us?