Start a docker service based on another service

Question

Is there a possibility to start a service on a specific node, based on another running service? (using Docker Swarm)

To make myself a little more clear:

I want to run Nextcloud on a different node than for example, a Typo3, to spare some resources on my Nextcloud node.

How would I write that in a compose?

question from:https://stackoverflow.com/questions/65938414/start-a-docker-service-based-on-another-service

Answer 1

Look into deploy and using labels:

Example:

        deploy:
            mode: replicated
            replicas: 1
            placement:
                constraints:
                - node.labels.NextcloudDaemon == true
            restart_policy:
                condition: any

The above example will run exactly 1 container, and only on the node you've already given the label of "NextcloudDaemon".