sslcheck-nagios

This plugin can be used with Nagios to check for a certificate's expiration date. If the expiration date is approaching and is within a configurable threshold, a warning will be issued. If the certificate is expired, Nagios will show critical.

Installing

Place in your Nagios plugins directory. On a Nagios server running Linux, for me, this is /usr/local/nagios/libexec.

Configuration

If you want the warning threshold to be something other than 30, set the WARNING_DAYS constant in the python file to whatever you desire. Of course, this is a global setting and will affect all instances of service monitoring that use this plugin.

In Nagios, configure a new command to use the plugin:

define command {
    command_name    check_ssl_certificate
    command_line    $USER1$/check_ssl_certificate -H $HOSTNAME$ -p $ARG1$
}

If you are monitoring a web service, set up $ARG1$ as '443' in the service configuration. I have not tested with services other than HTTPS but I don't see why it wouldn't work.

The command can be tested at the command line as well.

Known Issues

Sending an IP address as the hostname argument will likely cause an error. For this reason, you should use the $HOSTNAME$ variable instead of the $HOSTADDRESS$ variable. Make sure the host_name directive is correct for your host. For more information on the Nagios macros, see the Nagios docs here.

Contributing

Not much to this yet, so by all means, fork it and submit a PR if you like. I'm pretty much open.

Authors

• Nick Harvey - Initial work - James Madison University Libraries

License

This project is licensed under the MIT License - see the LICENSE.md file for details