An image for using mongodb within Docker containers.
Yet another container for running MongoDB?
Aren't you only supposed to run one process per container?
Well yes and no... the following are good examples of when multiple processes within one container might be necessary:
- automatically updating nginx proxy settings when a down-stream application server (nodejs, php, etc) restarts (and the IP changes)
- automatically updating HAProxy configuration to load balance to a group of down-stream application servers
- running a logging daemon to centralize log management (i.e. logentries, loggly, logstash)
- when you need to run a script on application server crash (to tidy something up), as the standard Docker container restart policies won't provide this
To use this image include
FROM smebberson/mongodb at the top of your
Dockerfile, or simply
docker run --name mongodb smebberson/mongodb.
By default, you'll probably notice MongoDB complaining about hugepage when it starts up. The s6 startup script has support to disable this, but you need to run the container in privileged mode:
docker run --privileged --name mongodb smebberson/mongodb`
This container comes setup as follows:
- s6 will automatically start mongod for you
- if mongod dies, it will automatically be restarted
- mongod is run as the mongodb user
To customise the start up process for mongod, during your
Dockerfile build process, copy across a file to
/etc/s6/mongodb/run. This file will be used to start
mongod. Within it, start
mongod after performing any setup steps as required.