Hello,
From this date, you can already run the latest releases of GeoNetwork in
docker containers.
To pull the images from dockerhub, you would type:
docker pull geocat/geonetwork:3.2.0
or:
docker pull geocat/geonetwork:3.0.5
More details on how to run the containers, set a custom data directory,
persist data or use postgreSQL as a backend, can be found at the docker hub
page:
https://hub.docker.com/r/geocat/geonetwork/
Have fun running GeoNetwork on Docker! 
Joana
--
Vriendelijke groeten / Kind regards,
*Joana Simoes <http://www.geocat.net/>Veenderweg 136721 WD BennekomThe
NetherlandsT: +31 (0)318 416664 <+31318416664>GeoCat bvhttp://geocat.net
<http://geocat.net>*