antondemidov/check_docker

Nagios plugin to check docker containers

check_docker

Nagios/NRPE compatible plugins for checking docker based services. Currently there are two nagios checks

• check_docker which checks docker container health
• check_swarm which checks health of swarm nodes and services

With check_docker 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?
• the presence of a container or containers matching specified names
• image version (experimental!), does the running image match that in the remote registry?

With check_swarm you can alert

• if a node is not joined to a docker swarm
• if a service is running in a swarm

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

These plugins require python 3. It is tested on 3.3 and greater but may work on older versions of 3.

Installation

With pip

pip3 install check_docker
--or--
pip install check_docker

With curl

curl -o /usr/local/bin/check_docker https://raw.githubusercontent.com/timdaman/check_docker/master/check_docker
curl -o /usr/local/bin/check_swarm https://raw.githubusercontent.com/timdaman/check_docker/master/check_swarm
chmod a+rx /usr/local/bin/check_docker /usr/local/bin/check_swarm

With wget

wget -O /usr/local/bin/check_docker https://raw.githubusercontent.com/timdaman/check_docker/master/check_docker
wget -O /usr/local/bin/check_swarm https://raw.githubusercontent.com/timdaman/check_docker/master/check_swarm
chmod a+rx /usr/local/bin/check_docker /usr/local/bin/check_swarm

check_docker Usage

usage: check_docker [-h]
                    [--connection [/<path to>/docker.socket|<ip/host address>:<port>]
                    | --secure-connection [<ip/host address>:<port>]]
                    [--timeout TIMEOUT]
                    [--containers CONTAINERS [CONTAINERS ...]] [--present]
                    [--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'])
  --present             Modifies --containers so that each RegEx must match at
                        least one container.
  --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.

check_swarm Usage

usage: check_swarm [-h]
                 [--connection [/<path to>/docker.socket|<ip/host address>:<port>]
                 | --secure-connection [<ip/host address>:<port>]]
                 [--timeout TIMEOUT]
                 (--swarm | --service SERVICE [SERVICE ...])

Check docker swarm.

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)
--swarm               Check swarm status
--service SERVICE [SERVICE ...]
                      One or more RegEx that match the names of the
                      services(s) to check.
usage: check_swarm [-h]
                 [--connection [/<path to>/docker.socket|<ip/host address>:<port>]
                 | --secure-connection [<ip/host address>:<port>]]
                 [--timeout TIMEOUT]
                 (--swarm | --service SERVICE [SERVICE ...])

Gotchas:

• When using check_docker with older versions of docker (I have seen 1.4 and 1.5) –status only supports ‘running’, ‘restarting’, and ‘paused’.
• When using check_docker, if no container is specified, all containers are checked. Some containers may return critcal status if the selected check(s) require a running container.