Work Around:
In the samba log you may see messages about kerberos authentication.
First step recommended is to try to join the DR back to the domain. If the GUI shows it connected, then drop and re-add.
This is an older version of the software, there were bug fixes with the latest release. Upgrading to the latest 4.x build is recommended.
Steps:
1. Re-add the DR back to the domain and monitor the behavior
if that doesn't work
2. Upgrade to the latest release.
