If Authentication is set to Server, the password server directive in smb.conf
must be set to the SMB server you want to use to authenticate users.
The Authentication Server field should also be editable if the Authentication
Mode is set to Domain.
Should be fixed in redhat-config-samba-1.0.1-6. Please test.
There is a stack of 64 bugs that have been in Modified state for a long period
of time. I am closing these as Rawhide now. If you find that the issue is not
fixed, please reopen this report.