How to disable/leave docker swarm mode when starting docker daemon?

Question

is there any way to disable/leave the swarm mode of docker when starting the daemon manually, eg dockerd --leave-swarm , instead of starting the daemon and leave the swarm mode afterwards, eg using docker swarm leave ?

Many thanks in advance, Aljoscha

Answer 1

I don't think this is anticipated by docker developers. When node leaves swarm, it needs to notify swarm managers, that it will not be available anymore.

Leaving swarm is a one time action and passing this as an configuration option to the daemon is weird. You may try to suggest that on docker's github, but I don't think it will have much supporters.

Perhaps more intuitive option would be to have ability to start dockerd in a way that communication to docker swarm manager would be suspended - so your dockerd is running only locally, but if you start without that flag (--local?) it would reconnect to swarm that it was attached before.