[Samba] Authentication to Secondary Domain Controller initially fails when PDC is offline

[James]

On 11/26/2015 11:12 AM, Ole Traupe wrote:
>
>>> Then you re-run your test with only DC2 up and running.
>>> Note DNS have need time to be updated if you are using others DNS 
>>> servers between clients and AD DCs.
>> The SOA RR identifies a primary DNS name server for the zone as the 
>> best source of information for the data within that zone and as a 
>> entity processing the updates for the zone.
>>
>> The NS resource record is used to notate which DNS servers are 
>> designated as authoritative for the zone. Listing a server in the NS 
>> RR, it becomes known to others as an authoritative server for the 
>> zone. This means that any server specified in the NS RR is to be 
>> considered an authoritative source by others, and is able to answer 
>> with certainty any queries made for names included in the zone.
>>
>> Much of the above was taken almost verbatim from online Microsoft 
>> tech documents.  I don't believe that DC's create NS records by default.
>
> You mean Samba DCs or DCs in general?
>
> I am not sure I understand the above. Do you suggest to create another 
> NS record for the Second_DC, or not to?
>
> In the resolv.conf on my member servers both DCs are listed as DNS 
> servers. I like to think that the member servers eventually ask the 
> second DNS server, if the first won't respond. This seems to be 
> reflected by ping taking more than 5 s for the first packet to arrive.
>
> BUT what does the second DNS server (Second_DC) reply? Which logon 
> server does it announce?
>
>
DNS can be very confusing. You do not need to create a NS record for 
your second DC if the zone is directory integrated. By default the DC is 
authoritative for that zone.

-- 
-James