[ceph-users] ceph-container: docker restart, mon's unable to join

Hi, In an attempt to get a (test) Mimic cluster running on Ubuntu 20.04 we are using docker with ceph-container images (ceph/daemon:latest-mimic). Deploying monitors and mgrs works fine. If however a monitor container gets stopped and started (i.e. docker restart) two out of three (with exception of mon initial member) mons won't join the cluster anymore and keep logging the following: /opt/ceph-container/bin/entrypoint.sh: Existing mon, trying to rejoin cluster... If docker is stopped, the mon directory "/var/lib/ceph/mon/$mon-name" removed and docker started again the mon is able to join the cluster. This directory is a persistent volume with correct permissions (167.167). No etcd cluster is in use here. We manually copied the /etc/ceph and /var/lib/ceph directories to the docker hosts. Any hints on how to make a mon container survive a reboot is welcome. Gr. Stefan P.s And yes, we know about Rook, kubernetes, etc. but that's not what want to use now.