mongod.service fails to start, causes shutdown

Hi, I'm trying to migrate from the previous version to :16. I've changed the folder structure and added the version file; then, when starting up the container, I see that mongod.service fails. That in turn causes systemd to wait a minute and then shut down the container. Any ideas what might go wrong here?

I'm using a fairly standard docker-compose file. Added caps are SYS_ADMIN and NET_ADMIN, tty is set to true, /run is tmpfs, /etc/localtime and /sys/fs/cgroup are mapped readonly.

Feb 10 00:01:24 mail systemd[1]: Starting High-performance, schema-free document-oriented database...
-- Subject: Unit mongod.service has begun start-up
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit mongod.service has begun starting up.
Feb 10 00:01:25 mail mongod[989]: about to fork child process, waiting until server is ready for connections.
Feb 10 00:01:25 mail mongod[989]: forked process: 1106
Feb 10 00:01:25 mail mongod[989]: ERROR: child process failed, exited with error number 100
Feb 10 00:01:25 mail systemd[1]: mongod.service: control process exited, code=exited status=100
Feb 10 00:01:25 mail systemd[1]: Failed to start High-performance, schema-free document-oriented database.
-- Subject: Unit mongod.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit mongod.service has failed.
--
-- The result is failed.
Feb 10 00:01:25 mail systemd[1]: Unit mongod.service entered failed state.
Feb 10 00:01:25 mail systemd[1]: mongod.service failed.

kvaps / docker-kolab

mongod.service fails to start, causes shutdown #23