title: Check health of NFS mounts
agents: linux
author: Mathias Kettner <mk@mathias-kettner.de>
license: GPL
distribution: check_mk
description:
 This check probes the availability of NFS mounts. The Linux agent sends the
 status of all NFS mounts, if the command line utility {maxwait} is available
 (it is is used to avoid hanging if the NFS server is not responding). The
 probe is done by trying a {stat -f} (system call {statfs(2)}) on the mount
 point. If that lasts longer then 2 seconds, then the server is considered
 to be not responding.

 When you install the Linux agent manually, please do not forget to also
 install {waitmax} into {/usr/bin}.  That file is shipped together with
 the agent. When {waitmax} is missing, the agent will silently omit the
 section {nfsmounts}.

 If the NFS mount is "stale", then {stat -f} returns immediately but with
 a size of {-1}. The check detects that and results in a warning state.

 Please note, that though this check outputs the current usage of the remote
 filesystem, no levels can be defined for the used space and no performance
 data is output. Please do a check for used space directly on the NFS server.

item:
 The mount point.

perfdata:
  This check does not provide performance data. The disk usage is assumedly
  measured on the file server itself.  Duplicating that data on all clients
  would unneccessarily create redundant RRDs.

inventory:
  All NFS mounts are found automatically. This is done
  by scanning {/proc/mounts}. The file {/etc/fstab}
  is irrelevant.