A dockerized xymon client to monitor
docker run -d --net=host --name xymon-client -e XYMONSERVERS="xymon.example.com" deweysasser/xymon-client
where 'xymon.example.com' is the name of your xymon server.
If you'd like to monitor disk space on anything other than
/var/lib/docker, you should mount a volume in the appopriate file
system into the container somewhere. Location is irrelevant.
See also the containerized Xymon server.