known-hosts

How can I write a program (script) to remove obsolete host keys from ~/.ssh/known_hosts?

I use a cluster of about 30 machines that have all recently been reconfigured with new OpenSSH host keys. When I try to log into one, I get this error message (many lines removed for brevity): @ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @ The fingerprint for the RSA key sent by the remote host is 52:bb:71:83:7e:d0:e2:66:9...

Where does Putty store known_hosts information on Windows?

How do I tell if Putty already knows about and has cached credentials for specific ssh servers? ...