Nagios Disk Check - Mountpoint or Filesystem?

If you mount filesystems under a specific mount point, and monitor them with Nagios, then be sure you understand what happens if the underlying file system goes away. With:

    /usr/lib/nagios/plugins/check_disk -w 15% -c 10% -p /a_mount_point

you’ll get the value from the containing file system. In this case /. If you’d rather know that your chosen mount point has actually gone away, and that you’re no longer checking what you thought you were, then add the -E option to the command. This will turn on exact path matching and catch that kind of error.