samba - Jul 2019 - DNS not working, samba not listening on port 53

>sudo systemctl stop systemd-resolved
>sudo systemctl disable systemd-resolved.service
>
>Rowland
Now systemd-resolved is inactive, but samba still does not listen..

root at natter:/home/joachim# systemctl start samba-ad-dc
Job for samba-ad-dc.service failed because a timeout was exceeded.
See "systemctl status samba-ad-dc.service" and "journalctl
-xe" for details.
root at natter:/home/joachim# journalctl -xe
Jul 13 21:23:30 natter winbindd[1874]: [2019/07/13 21:23:30.688963,  0]
../../source3/winbindd/winbindd_cache.c:3166(initialize_win
Jul 13 21:23:30 natter winbindd[1874]:   initialize_winbindd_cache: clearing
cache and re-creating with version number 2
Jul 13 21:23:30 natter winbindd[1874]: [2019/07/13 21:23:30.696132,  0]
../../lib/util/become_daemon.c:136(daemon_ready)
Jul 13 21:23:30 natter winbindd[1874]:   daemon_ready: daemon 'winbindd'
finished starting up and ready to serve connections
Jul 13 21:26:24 natter systemd-timesyncd[650]: Synchronized to time server
91.189.89.199:123 (ntp.ubuntu.com).
Jul 13 21:27:53 natter systemd[1]: samba-ad-dc.service: Start operation
timed out. Terminating.
Jul 13 21:27:53 natter samba[1859]: task[s3fs_parent][1859]: [2019/07/13 21:
27:53.238892,  0] ../../source4/smbd/process_standard.c
Jul 13 21:27:53 natter samba[1859]: task[s3fs_parent][1859]:
sigterm_signal_handler: Exiting pid 1859 on SIGTERM
Jul 13 21:27:53 natter samba[1862]: task[nbtd][1862]: [2019/07/13
21:27:53.239094,  0] ../../source4/smbd/process_standard.c:84(sig
Jul 13 21:27:53 natter samba[1862]: task[nbtd][1862]:
sigterm_signal_handler: Exiting pid 1862 on SIGTERM
Jul 13 21:27:53 natter samba[1875]: task[dnsupdate][1875]: [2019/07/13
21:27:53.239135,  0] ../../source4/smbd/process_standard.c:8
Jul 13 21:27:53 natter samba[1875]: task[dnsupdate][1875]:
sigterm_signal_handler: Exiting pid 1875 on SIGTERM
Jul 13 21:27:53 natter winbindd[1874]: [2019/07/13 21:27:53.246070,  0]
../../source3/winbindd/winbindd.c:243(winbindd_sig_term_han
Jul 13 21:27:53 natter winbindd[1874]:   Got sig[15] terminate (is_parent=1)
Jul 13 21:27:53 natter systemd[1]: samba-ad-dc.service: Failed with result
'timeout'.
Jul 13 21:27:53 natter systemd[1]: Failed to start Samba Active Directory
Domain Controller.
-- Subject: Unit samba-ad-dc.service has failed
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit samba-ad-dc.service has failed.
--
-- The result is RESULT.

root at natter:/home/joachim# systemctl status samba-ad-dc.service
? samba-ad-dc.service - Samba Active Directory Domain Controller
   Loaded: loaded (/etc/systemd/system/samba-ad-dc.service; enabled; vendor
preset: enabled)
   Active: failed (Result: timeout) since Sat 2019-07-13 21:27:53 UTC; 2min
27s ago
  Process: 1839 ExecStart=/usr/sbin/samba -D (code=exited, status=0/SUCCESS)

Jul 13 21:27:53 natter samba[1859]: task[s3fs_parent][1859]: [2019/07/13 21:
27:53.238892,  0] ../../source4/smbd/process_standard.c:
Jul 13 21:27:53 natter samba[1859]: task[s3fs_parent][1859]:
sigterm_signal_handler: Exiting pid 1859 on SIGTERM
Jul 13 21:27:53 natter samba[1862]: task[nbtd][1862]: [2019/07/13
21:27:53.239094,  0] ../../source4/smbd/process_standard.c:84(sigt
Jul 13 21:27:53 natter samba[1862]: task[nbtd][1862]:
sigterm_signal_handler: Exiting pid 1862 on SIGTERM
Jul 13 21:27:53 natter samba[1875]: task[dnsupdate][1875]: [2019/07/13
21:27:53.239135,  0] ../../source4/smbd/process_standard.c:84
Jul 13 21:27:53 natter samba[1875]: task[dnsupdate][1875]:
sigterm_signal_handler: Exiting pid 1875 on SIGTERM
Jul 13 21:27:53 natter winbindd[1874]: [2019/07/13 21:27:53.246070,  0]
../../source3/winbindd/winbindd.c:243(winbindd_sig_term_hand
Jul 13 21:27:53 natter winbindd[1874]:   Got sig[15] terminate (is_parent=1)
Jul 13 21:27:53 natter systemd[1]: samba-ad-dc.service: Failed with result
'timeout'.
Jul 13 21:27:53 natter systemd[1]: Failed to start Samba Active Directory
Domain Controller.

root at natter:/home/joachim# cat /var/log/samba/log.samba
[2019/07/13 21:23:30.337403,  0]
../../source4/smbd/server.c:587(binary_smbd_main)
  samba version 4.10.5-Ubuntu started.
  Copyright Andrew Tridgell and the Samba Team 1992-2019
[2019/07/13 21:23:30.461469,  0]
../../source4/smbd/server.c:773(binary_smbd_main)
  binary_smbd_main: samba: using 'standard' process model
[2019/07/13 21:23:30.479958,  0]
../../lib/util/become_daemon.c:136(daemon_ready)
  daemon_ready: daemon 'samba' finished starting up and ready to serve
connections
[2019/07/13 21:27:53.238892,  0]
../../source4/smbd/process_standard.c:84(sigterm_signal_handler)
  sigterm_signal_handler: Exiting pid 1859 on SIGTERM
[2019/07/13 21:27:53.239094,  0]
../../source4/smbd/process_standard.c:84(sigterm_signal_handler)
[2019/07/13 21:27:53.239135,  0]
../../source4/smbd/process_standard.c:84(sigterm_signal_handler)
  sigterm_signal_handler: Exiting pid 1862 on SIGTERM
  sigterm_signal_handler: Exiting pid 1875 on SIGTERM

Thanks for any hint,
Joachim