[Samba] Join Samba to a Windows AD 'WERR_DS_NO_CROSSREF_FOR_NC'

[Rowland penny]

On 21/07/2019 10:22, René Schmidt wrote:
> Hello Rowland,
>
> I have started again:
> - new Window Server 2012 R2 installed
> - DNS server set up
> - once again the Ubunut 18.04 freshly installed
> - entered the IP of the Windows server as DNS server
> - Installed the Samba Packet from the official Ubunut source:
> dpkg -l | grep samba
> ii  python-samba                          	2:4.7.6+dfsg~ubuntu-0ubuntu2.11   amd64        Python bindings for Samba
> ii  samba                                 	2:4.7.6+dfsg~ubuntu-0ubuntu2.11   amd64        SMB/CIFS file, print, and login server for Unix
> ii  samba-common                          2:4.7.6+dfsg~ubuntu-0ubuntu2.11   all          common files used by both the Samba server and client
> ii  samba-common-bin                  2:4.7.6+dfsg~ubuntu-0ubuntu2.11   amd64        Samba common files used by both the server and the client
> ii  samba-dsdb-modules	2:4.7.6+dfsg~ubuntu-0ubuntu2.11   amd64        Samba Directory Services Database
> ii  samba-libs:amd64		2:4.7.6+dfsg~ubuntu-0ubuntu2.11   amd64        Samba core libraries
> ii  samba-vfs-modules		2:4.7.6+dfsg~ubuntu-0ubuntu2.11   amd64        Samba Virtual FileSystem plugins
>
>
> if I am now
> samba-tool domain join mydom.local DC -U "MYDOM\administrator" -d3
> I get the following message:
> Adding 1 remote DNS records for SAD. mydom.local
> Using binding ncacn_ip_tcp: WAD. mydom.local [, sign]
> resolve_lmhosts: Attempting lmhosts lookup for name WAD. mydom.local <0x20>
> resolve_lmhosts: Attempting lmhosts lookup for name WAD. mydom.local <0x20>
> Adding DNS A record WAD.schmidthome.local for IPv4 IP: 192.168.159.98
> Join failed - cleaning up
Anything after this point is an artefact of the failure and can be ignored.
> Do you have an idea?
> The DNS entry is created on the Windows server for the Samba server.

You are getting closer, the join is now failing at the last hurdle and 
we had this very recently with a user trying to join to Windows 2003 DC.

The cure was to stop the join creating the DC records.

Find 'join.py (/usr/lib/python2.7/dist-packages/samba/join.py on my DC) 
and open it in your favourite editor, find these lines:

             if ctx.dns_backend != "NONE":
                 ctx.join_add_dns_records()
                 ctx.join_replicate_new_dns_records()

Line 1405 in my version, under '    def do_join(ctx):'

just comment out those three lines, save & close, then try the join again.

Rowland