About
=====
**check_mount** is a Nagios/Icinga plugin for checking for the presence of
mounted filesystems.
Sometimes, it is only important to monitor the presence of a mount, and not
the amount of free (or used) storage on that filesystem. For example, when
monitoring NFS clients it may be redundant to use **check_disk** to monitor
the NFS mounts because the amount of free storage on those mounts is monitored
elsewhere. Additionally, **check_disk** can give a false negative if the
filesystem is not mounted at all, but the directory used as a mount point is
present.
Usage
=====
.. code:: text
usage: check_mount [-h] [-w RANGE] [-c RANGE] [-p PATH] [-t TYPE] [-M PATH]
[-v]
optional arguments:
-h, --help show this help message and exit
-w RANGE, --warning RANGE
Generate warning state if number of mounts is outside
this range
-c RANGE, --critical RANGE
Generate critical state if number of mounts is
outside this range
-p PATH, --path PATH A mount point to check to ensure it is present. May
be specified more than once. This option is
incompatible with --type.
-t TYPE, --type TYPE Only check mounts of a particular type. If specified
more than once, the count of present mounts will
include all mounts of all types specified. This
option is incompatible with --path.
-M PATH, --mount-path PATH
Override the path to mount(8) [Default: /sbin/mount]
-v, --verbose Increase output verbosity (use up to 3 times).
Counting Mounts
---------------
If you're only concerned with making sure the correct number of mounts are
present, you can set a warning/critical range.
To warn if anything other than exactly 5 filesystems are mounted::
check_mount -w 5:5
To retun critical if fewer than 5 filesystems are mounted, and a warning if
more than 5 are mounted::
check_mount -w :5 -c 5:
Checking Mounts by Type
-----------------------
If you're only concerned with a particular type of mount, for example you want
to ensure that all of your network mounts are present, but ignore any others,
you can supply a list of filesystem types to **check_mount**.
To look only at AFS and NFS mounts, and to expect exactly 2 total mounts (one
of each)::
check_mount -t NFS -t AFS -w 2:2
By default, **check_mount** ignores several filessytem pseudo-types. Ignoring
these can be overridden by specifying them, along with any other types you
would like to check, on the command line. Filesystem types ignored by default
are::
autofs bpf cgroup cgroup2 debugfs
devpts devtmpfs hugetlbfs mqueue proc
pstore securityfs sysfs tmpfs
Checking Specific Mount Points
------------------------------
If you wish to check specific mount points you can specify one or more on the
command line with the `--path` argument::
check_mount -p /home -w1:1
Unlike other modes of operation, when checking specific mount points
**check_mount** applies the warning and critical ranges to each individual
mount, rather than the sum of all mounts. This allows **check_mount** to
include the names of specific mounts in its error message. So, if you're
checking three different mount points this way, and you want to return a
critical alert if any of them are missing, you would use a command like this::
check_mount -p /home -p /var -p /opt -c1:1