[Samba] How to determine DNS anomaly

[Rowland Penny]

On Fri, 2022-05-06 at 08:54 +0200, Hakim Liso via samba wrote:
> Resolve conf Looks like this for MY.DOMAIN
> 
> DC01 192.168.50.11
> search MY
> nameserver 10.0.1.9
> nameserver 192.168.50.11
> 
> DC02 10.0.1.9
> search MY
> nameserver 192.168.50.11
> nameserver 10.0.1.9

As I said, a DC should use itself as it its nameserver, so I would
remove 'nameserver 10.0.1.9' from /etc/resolv.conf on DC01 and
'nameserver 192.168.50.11' from /etc/resolv.conf on DC02. Also the
search line should use the dns domain, not the NetBios domain name,
'MY' is wrong, 'my.domain' would be correct.

> 
> But this was working without any Problems with the private ips before
> the Errors on the backup appeared. I doubt changing the own ips to
> the loopback address will fix my issues.
> I’ve expanded testing and it seems only ldap lookup doesnt work for
> dc02 and i noticed that there keeps on being a static A Record
> generated Dc01 10.0.1.9, which seems wrong. 

That is possibly because of your incorrect resolv.conf files.

> 
> Server:         192.168.50.11
> Address:        192.168.50.11#53
> 
> Name:   dc01.my.domain
> Address: 192.168.50.11
> Name:   dc01.my.domain
> Address: 10.0.1.9
> 
> I kept deleting it but it keeps come back. So something must be wrong
> with Dynamic DNS
> 
> Also there wasnt any NS entry in the Reverse lookup of the dc02s Site
> but i guess that was because i didnt join the dc in a specific site. 

Yes, why are you using 'sites', are your DC's in different locations ?

> Nevertheless the Entries did not complement.
> 
> Also there is entries for DC01 only in Site 2/_tcp for
> _gc,_ldap,_kerberos which has to be switched with dc02 i guess. Also
> the my.domain/_tcp contains gc,Kerberos,kpasswd,ldap entries for DC01
> only. DNS Update does not seem to have the Right entries.

Fix your /etc/resolv.conf files and they should get created correctly.

Rowland