Not sure which log to grab and post, but I've configured a pair of AD servers as authentication sources (within the same domain). Both are local to the UTM. I've also configured group membership sync.
About every 2 hours I get the following alert:
There was an error synchronizing subscribed groups. The Sophos UTM will
continue to operate with a locally cached copy of the data but will be
unable to update from Directory Services until the issue is resolved.
Error was:
failed to run samba command on ACTIVE.DIRECTORY, exiting now
--
System Uptime : 1 day 2 hours 51 minutes
System Load : 0.83
System Version : Sophos UTM 9.171-2
Please refer to the manual for detailed instructions.
I believe I can force the error if I go to Definitions & Users > Authentication Services > Advanced > Active Directory Group Membership Synchronization > Synchronize Now.
If someone can suggest logs / config data to post to diagnose, I'm more than happy to do so.