The following error is seen on the master servevr:
2019-12-06 14:30:46 ERROR [ucs-slave] rsync to local sysvol exited with 23 (rsync: change_dir "/var/cache/univention-samba4/sysvol-sync/ucs-slave" failed: No such file or directory (2)rsync error: some files/attrs were not transferred (see previous errors) (code 23) at main.c(1196) [sender=3.1.2])
This indicates some minor issues in syncing the sysvol from the slave server “ucs-slave”.
It should fix it by itself otherwise you can increase debug level for the sysvol sync:
ucr set samba4/sysvol/sync/debug=true