[Samba] Samba 4.0.6 update - login issues

[Kristofer Pettijohn]

I updated all 14 of our Domain Controllers to 4.0.6, and now I am having random authentication issues.

Our radius server uses ntlm_auth to authenticate users.  Every morning at 3AM since the update, ntlm_auth fails to authenticate.  If I restart Samba 4 on the domain controller that the radius server connects to, then authentication works again.

In addition, I am running Samba 3.5.10-125.el6 with winbind on all of our file servers.  Users randomly become unable to authenticate and connect to file shares.  If I restart Samba 4 on the domain controller closest to the file server, they are able to authenticate again.  Simply restarting winbind doesn't resolve it.  I need to restart the samba daemons on the domain controller.

What might be causing this?