Important changes that seem to affect COOL docker versions from v21.11.3.6 on (multiple domains setup)

@tim.s has discovered something important for you guys dealing with collabora docker throwing problems when working with multiple domains

It appears that Collabora configuration has changed in the latest releases. I realised when I checked the docker logs:

-e ERR: Use of domain variable is not supported. First host/domain who tries to connect to COOL is always allowed.
To allow multiple host and its aliases use something like this and pass it as env variable:
For more info:

The linked article confused me a bit, and I did not get it running. Then I discovered that the mentioned configuration apparently will only be available in the upcoming docker release ( )

For the moment one has to change it inside the docker file. I managed to get it running again with the description mentioned here:

Thought this may be helpful to others as well.

original posting here


Many thanks for heads-up @JimmyKater: Just tested with current CODE image and it works as described (surprise - RTFM works!)

excerpt from docker-compose.yaml file

    image: collabora/code:
      - aliasgroup1=${NEXTCLOUD1}
      - aliasgroup2=${NEXTCLOUD2}

excerpt from .env file


both Nextclouds 23.0.3 can access Collabora without issues.

Interesting point: it seems 192.168.x.x IPs are allowed by default (?!):

1 Like

@wwe discovered the following hint

Big thanks to him for that valuable hint! :heart_eyes_cat:

so you better read the whole thing