Docker-monitor-service

This service keeps track of containers defined within the connected docker daemon and keeps their state up to date in the database.

usage

This docker image needs access to a docker socket. If you are using a usernamespace, it is recommended to run this docker using the --userns='host' switch. On some systems it may also need the --privileged flag.

A typical docker compose file may look like this:

version: "3"
services:
  monitor:
    image: lblod/docker-monitor-service
    links:
      - database:database
    privileged: true
    userns_mode: "host"
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
  database:
    image: tenforce/virtuoso:1.3.1-virtuoso7.2.4
    environment:
      SPARQL_UPDATE: "true"
      DEFAULT_GRAPH: "http://mu.semte.ch/application"

docker run -d --userns=host --privileged -v /var/run/docker.sock:/var/run/docker.sock lblod/docker-monitor-service

On startup the container updates the container metadata in the triplestore with the data fetched through the docker daemon about running as well as stopped containers. Hence, the more docker containers on the system, the longer the initialization procedure will take.

configuration

The docker image can be configured using the following environment flags:

• MONITOR_DOCKER_SOCKET: default: file:///var/run/docker.sock specify a different url for the docker socket. currently supports the file and http scheme. For http use http://IP_OR_DOMAIN:PORT.
• MONITOR_FILTER_LABEL: default: none, if set only keep track of containers that have this label set.
• MU_SPARQL_ENDPOINT: default 'http://database:8890/sparql, sparql endpoint to connect to
• MONITOR_SYNC_INTERVAL: default: 10000 is the interval in milliseconds between syncs of the docker daemon container state to the database resulting in deltas being sent (if any update to the containers on the system occurred).