On one of our Ubuntu 14.04 servers, running Winbind 4.1.6+dfsg-1ubuntu2.14.04.9, Winbind periodically forgets who I am, resulting in strange errors like ssh aborting with an "unknown uid" error whenever I try to run it.
Whenever the system is in this state, getent passwd works just fine; it correctly lists every user in the domain, and it fixes Winbind's forgetfulness so that user resolution works again.
The problem is very sporadic (maybe once a week?) and only seems to affect one of our Linux servers.
Winbind's log files aren't much help (using a log level of 2). The problem most recently occurred this morning, but the last log message is from a couple of days ago:
[2015/12/14 07:14:04.576645, 0] ../source3/rpc_client/cli_netlogon.c:462(rpccli_netlogon_sam_network_logon) rpccli_netlogon_sam_network_logon: credentials chain check failed
