reverse mapping failed

When you ssh into a machine from the same subnet, it tries to reverse-lookup you IP address. When that failes, sshd writes a message in your /var/log/auth.log saying:

reverse mapping checking getaddrinfo for rfc-1918 [ip_address_here] failed – POSSIBLE BREAK-IN ATTEMPT!

To stop getting that, add the names of your subnet machines in /etc/hosts

~ by azimout on November 1, 2009.