[Samba] Suppressing DOMAIN on AD-DC Machine

[Nick Piggott]

Hello,

Here's my setup:
* Ubuntu 18.04 LTS
* Samba 4.7.6
* Active Directory (provided by Samba)
* Postfix 3.3.0
* Mailutils 3.4

On this machine, my AD usernames are showing in the format
DOMAIN\username

All the machines in the AD have a directive in their /etc/samba/smb.conf
file
winbind use default domain = yes
however this doesn't work on this machine acting as the AD-DC, and looking
through the mailing list, this is by design, and unlikely to change. (It
does work on the workstations where users are just shown as their username).

Having the format DOMAIN\username is making using Postfix / Mailutils very
difficult. Originating emails ("From: DOMAIN\username at domain.com") are
being rejected by mail relays, and case folding on Postfix means I end up
with two mail files for each user in /var/mail (DOMAIN\username and
domain\username).

Is there any way to suppress the DOMAIN section of a username on the AD-DC
machine? Or an alternative approach to fixing this issue. (I've looked at
re-writing in Postfix, and it's ugly).

Thanks


Nick