[Samba] Samba DNS fails when queried with nslookup commands

[Rowland penny]

On 12/08/2020 21:49, James Atwell via samba wrote:
> 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
>
Last time I set up a DC on 18.04 I did this:

sudo systemctl stop systemd-resolved
sudo systemctl disable systemd-resolved.service

Rowland