Uninstall UCP

Docker UCP is designed to scale as your applications grow in size and usage. You can add and remove nodes from the cluster to make it scale to your needs.

You can also uninstall Docker Universal Control Plane from your cluster. In this case the UCP services are stopped and removed, but your Docker Engines will continue running in swarm mode. You applications will continue running normally.

If you wish to remove a single node from the UCP cluster, you should instead Remove that node from the cluster.

After you uninstall UCP from the cluster, you can’t enforce role-based access control to the cluster or centrally monitor and manage the cluster. You can no longer join new nodes to the cluster using docker swarm join.

To uninstall UCP, log in to a manager node using ssh, and run the following command:

$ docker container run --rm -it \
  -v /var/run/docker.sock:/var/run/docker.sock \
  --name ucp \
  docker/ucp:2.2.17 uninstall-ucp --interactive

This runs the uninstall command in interactive mode, so that you are prompted for any necessary configuration values. Running this command on a single manager node will uninstall UCP from the entire cluster. Check the reference documentation to learn the options available in the uninstall-ucp command.

Swarm mode CA

After uninstalling UCP, the nodes in your cluster will still be in swarm mode, but you can’t join new nodes until you reinstall UCP, because swarm mode relies on UCP to provide the CA certificates that allow nodes in the cluster to identify one another. Also, since swarm mode is no longer controlling its own certificates, if the certificates expire after you uninstall UCP, the nodes in the swarm can’t communicate at all. To fix this, either reinstall UCP before the certificates expire or disable swarm mode by running docker swarm leave --force on every node.

Where to go next

• Scale your cluster