During a migration we encountered the following problem old situation: samba listening on 192.168.0.200 and 10.0.1.80 eth0 had ip 192.168.0.200 eth1 had ip 10.0.1.80 relevant entries in smb.conf interfaces = 192.168.0.200 , 10.0.1.80 bind interfaces only = yes =>all was working ok ===== new situation: samba listening on 192.168.0.200 and 10.0.1.80 only eth1 had an ip address assigned: 10.0.1.80 we forgot to modify the interfaces entry in smb.conf =>the result was that after restarting samba (for some reason we did restart it, but changed nothing in the config..) both nmbd and smbd were running BUT trying to log in from the windows clients on the domain we received every time "username or password incorrect". Looking in the logs it said [2011/05/23 17:10:21.287566, 0] auth/auth_sam.c:493(check_sam_security) check_sam_security: make_server_info_sam() failed with 'NT_STATUS_NO_SUCH_USER' [2011/05/23 17:10:24.309874, 0] passdb/pdb_get_set.c:212(pdb_get_group_sid) pdb_get_group_sid: Failed to find Unix account for TheUserTryingToLogIn The problem was resolved by removing the reference to the 192.168.0.200 ip in the 'interfaces' entry in smb.conf. The reason i file this as a bug is that nor smbd nor nmbd communicate clearly about what the problem is, but instead give the impression that there is something wrong with the link with the user db (openldap in this case). I have to admit that i DIDNT run testparm beforehand, so i dont know if it would have generated warnings... (not going to reverse the situation atm, since it's working and in use by users, they'll probable splice my head if i break it now)