winbindd silently fails to start because it tries to unlink /var/run/samba/winbindd_cache.tdb which does not exist Creating the file by hand solves the problem until the next restart strace: ... stat64("/var/run/samba", {st_mode=S_IFDIR|0755, st_size=576, ...}) = 0 unlink("/var/run/samba/winbindd_cache.tdb") = -1 ENOENT (No such file or directory) stat64("/var/run/samba", {st_mode=S_IFDIR|0755, st_size=576, ...}) = 0 exit_group(1) = ?
This is a packaging problem, it was present both in the Ubuntu packages and my debian packages on samba.org, and was caused by a bug in the fhs.patch made originally by debian developers. I fixed my packages and from my analysis this shouldn't happen in vanilla samba. Closing the bug, reopen if there are still problems.