As the title suggests, I would like to remotely monitor SSH authentication (not just TCP service) on a remote host. Occasionally, this host likes to have the service running but refuse logins through PAM.
There is check_ssh, which only monitors the TCP service, and there is check_by_ssh, which executes a remote command via ssh for monitoring purposes. I could hijack the latter, but it requires pub key authentication. I need to monitor with a plain SSH login. I realize the security implications.
Is a custom Nagios plugin that executes SSH my best bet?