check_geom (Visit this link)

The plugin is designed to accept checks to any FreeBSD GEOM class. However, to all intents and purposes, only certain GEOM classes are supported at this time.

The plug in accepts two arguments. The GEOM class you are monitoring, and the name of the volume. Selecting a volume to monitor is no longer mandatory (as in earlier versions). You can simply select a GEOM class and all volumes of that class can be shown in the output.

Usage: check_geom (geom class) {volume}

Examples:
* check_geom mirror gm0
* check_geom stripe

Currently supported GEOM classes in this version are:-
* mirror - (RAID 1 mirrored volumes)
* stripe - (RAID 0 striped volumes)
* raid3 - (RAID 3 volumes)
* concat - (Concatenated volumes)
* shsec - (Shared secret volumes)

Future editions of this plugin may also monitor gvinum, gvirstor, gmultipath, and gjournal volumes (where feasible).

The plugin returns an OK result if the volume(s) are functioning OK. In the case of a hard disk failure or volume dissapearance/non-existance, the plug in will almost always result in a CRITICAL event.

In this version, assuming no other monitored volumes are CRITICAL, WARNING events are only ever issued if you are have at least two components still functioning in a mirrored volume, or you are rebuilding a raid3. A WARNING result will display the "percent complete" rebuild details in Nagios for you to monitor too.

The check_geom plugin can also work under nrpe.

Please contact me should you notice any bugs, or wish to add features.