thierry@bino:~$ sudo systemctl unmask samba-ad-dc.service
Removed /etc/systemd/system/samba-ad-dc.service.
thierry@bino:~$ sudo systemctl start samba-ad-dc.service
thierry@bino:~$ sudo systemctl status samba-ad-dc.service
● samba-ad-dc.service - Samba AD Daemon
   Loaded: loaded (/lib/systemd/system/samba-ad-dc.service; disabled; vendor preset: en
   Active: active (running) since Fri 2018-10-26 13:05:48 UTC; 15s ago
     Docs: man:samba(8)
           man:samba(7)
           man:smb.conf(5)
 Main PID: 3785 (samba)
   Status: "smbd: ready to serve connections..."
    Tasks: 22 (limit: 2320)
   CGroup: /system.slice/samba-ad-dc.service
           ├─3785 /usr/sbin/samba --foreground --no-process-group
           ├─3798 /usr/sbin/samba --foreground --no-process-group
           ├─3800 /usr/sbin/samba --foreground --no-process-group
           ├─3803 /usr/sbin/samba --foreground --no-process-group
           ├─3804 /usr/sbin/samba --foreground --no-process-group
           ├─3805 /usr/sbin/samba --foreground --no-process-group
           ├─3806 /usr/sbin/smbd -D --option=server role check:inhibit=yes --foreground
           ├─3808 /usr/sbin/samba --foreground --no-process-group
           ├─3809 /usr/sbin/samba --foreground --no-process-group
           ├─3810 /usr/sbin/samba --foreground --no-process-group
           ├─3811 /usr/sbin/samba --foreground --no-process-group
           ├─3812 /usr/sbin/samba --foreground --no-process-group
           ├─3813 /usr/sbin/samba --foreground --no-process-group
thierry@bino:~$ sudo systemctl enable samba-ad-dc.service
Synchronizing state of samba-ad-dc.service with SysV service script with /lib/systemd/systemd-sysv-install.
Executing: /lib/systemd/systemd-sysv-install enable samba-ad-dc