[Samba] Samba DNS fails when queried with nslookup commands

[James Atwell]

Hello,

      Having issues with a DC not responding to DNS requests. OS is 
Ubuntu 18.04.4 LTS. Samba version 4.12.2 compiled from source. Checking 
to see what is listening on port 53 reports;

@soldc4:~# netstat -tulpn | grep ":53"
tcp        0      0 127.0.0.53:53 0.0.0.0:*               LISTEN      
2935/systemd-resolv
tcp6       0      0 :::53 :::*                    LISTEN      
2694/samba: task[dn
udp        0      0 127.0.0.53:53 0.0.0.0:*                           
2935/systemd-resolv
udp6       0      0 :::53 :::*                                
2694/samba: task[dn


How do I disable systemd-resolve and ensure only samba is listening on 
port 53 for DNS requests?  You can see below nslookup succeeds when 
querying another server in the network but fails on this one.

root at soldc4:~# nslookup google.com soldc1
Server:         soldc1
Address:        172.16.23.28#53

Non-authoritative answer:
Name:   google.com
Address: 172.217.7.238
Name:   google.com
Address: 2607:f8b0:4004:806::200e

root at soldc4:~# nslookup google.com soldc4
;; connection timed out; no servers could be reached


Thanks in advance for any help.

-James