check-docker 1.0.3

NRPE plugin for monitoring Docker containers

check_docker

This a nagios/NRPE compatible plugin for checking docker containers. So far you can use it to check and alert on

• memory consumption in absolute units (bytes, kb, mb, gb) and as a percentage (0-100%) of the container limit.

• CPU usages as a percentage (0-100%) of container limit.

• automatic restarts performed by the docker daemon

• container status, i.e. is it running?

• container health checks are passing?

• uptime, i.e. is it able to stay running for a long enough time?

• image version (experimental!), does the running image match that in the remote registry?

This check can communicate with a local docker daemon socket file (default) or with local or remote docker daemons using secure and non-secure TCP connections.

This plugin requires python 3. It is tested on 3.3 and greater but may work on older versions of 3.

Usage

usage: check_docker.py [-h]
                       [--connection [/<path to>/docker.socket|<ip/host address>:<port>]
                       | --secure-connection [<ip/host address>:<port>]]
                       [--timeout TIMEOUT]
                       [--containers CONTAINERS [CONTAINERS ...]]
                       [--cpu WARN:CRIT] [--memory WARN:CRIT:UNITS]
                       [--status STATUS] [--health] [--uptime WARN:CRIT]
                       [--version] [--restarts WARN:CRIT]

Check docker containers.

optional arguments:
  -h, --help            show this help message and exit
  --connection [/<path to>/docker.socket|<ip/host address>:<port>]
                        Where to find docker daemon socket. (default:
                        /var/run/docker.sock)
  --secure-connection [<ip/host address>:<port>]
                        Where to find TLS protected docker daemon socket.
  --timeout TIMEOUT     Connection timeout in seconds. (default: 10.0)
  --containers CONTAINERS [CONTAINERS ...]
                        One or more RegEx that match the names of the
                        container(s) to check. If omitted all containers are
                        checked. (default: ['all'])
  --cpu WARN:CRIT       Check cpu usage percentage taking into account any
                        limits. Valid values are 0 - 100.
  --memory WARN:CRIT:UNITS
                        Check memory usage taking into account any limits.
                        Valid values for units are %,b,k,m,g.
  --status STATUS       Desired container status (running, exited, etc).
                        (default: None)
  --health              Check container's health check status
  --uptime WARN:CRIT    Minimum container uptime in seconds. Use when
                        infrequent crashes are tolerated.
  --version             Check if the running images are the same version as
                        those in the registry. Useful for finding stale
                        images. Only works with public registry.
  --restarts WARN:CRIT  Container restart thresholds.

Gotchas:

• When using this with older versions of docker (I have seen 1.4 and 1.5) –status only supports ‘running’, ‘restarting’, and ‘paused’.

• When no container is specified all containers are checked. Some containers will return critcal status because the selected check(s) require a running container.