[Samba] Dynamic DNS updates by the AD member

[Shyam Prasad N]

Hi,

I'm trying to get my Linux VMs to join the Microsoft AD domian.
Although I was able to successfully join the domain and the DNS record was
created successfully, I noticed that the DNS records were not updated when
the IP address for the Linux member VM changed eventually. In case of a
Windows member VM, it looks like the DNS record does get updated.

After many google searches and going through several scattered
documentation on the internet, it sounds like there are two ways that the
DNS records are updated. One is where the DHCP server or the DC keeps the
DNS records for all the domain members updated. Second is where the client
triggers the DNS record update when there is a change.

It looks like this is exactly what the dyndns_update feature of sssd is
meant to be.
https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/windows_integration_guide/sssd-dyndns
However, I don't see a similar feature advertised for winbind.

I did some more digging into this. Downloaded the sssd codebase (
https://pagure.io/SSSD/sssd.git).
It looks like a background task is triggered if this config option is set,
which keeps checking and syncing with the dns server (see ad_dyndns_init).

However, I don't see a similar behavior in the samba source code. I assume
that any DNS update in an AD environment goes through net_update_dns() ->
DoDNSUpdate() path. However, I don't see this being called by anything
other than the "net ads ..." commands.

Is there a reason why winbindd cannot do something similar and keep the DNS
book keeping?
Or am I missing something here?

Thanks in advance for the replies.

-- 
-Shyam