[Samba] internal DNS not forwarding

[Andrea Ballarati]

Hello,
I am trying to setup a samba4 AD dc in my network using smb-tool.
Everything seems to work except DNS forwarding.
If I query for the dc
root at dc:~# nslookup dc.local.domain.it
I get the correct answer:
root at dc:~# nslookup dc
Server:         aaa.bbb.ccc.ddd
Address:        aaa.bbb.ccc.ddd#53

Name:   dc.xxxx.yyyy.it
Address: aaa.bbb.ccc.ddd

but if I query for an external domain:
root at dc:~# nslookup www.nasa.gov
Server:         aaa.bbb.ccc.ddd
Address:      aaa.bbb.ccc.ddd#53

Non-authoritative answer:
*** Can't find www.nasa.gov: No answer

Here is my smb.conf:
[global]
         workgroup = XXXX
         realm = XXXX.YYYY.IT
         netbios name = DC
         server role = active directory domain controller
         idmap_ldb:use rfc2307 = yes
         dns forwarder = 8.8.8.8

[netlogon]
         path = /var/lib/samba/sysvol/xxxx.yyyy.it/scripts
         read only = No

[sysvol]
         path = /var/lib/samba/sysvol
         read only = No

and my resolv.conf

search xxxx.yyyy.it
nameserver aaa.bbb.ccc.ddd

Thank you in advance
Andrea