AD doesn't start

[BCrime]

Hi there

We got two DC's with DNS at the Main Site.
There's only one Domain.
The entry for DNS in the Networkcard is first DNS himself,
second the other DC.
When we reboot both of them at the same time we have troubles
to start Active Directory, we have to enter a third DNS in the Network settings from another location where the DNS Server is running.
But they cannot start if there's no DNS Server alive.
If i disconnect the LAN Cable from the DC and try to start the DC the Server starts up veeeery slooowly and the AD will not start either, because there's no DNS running.
And the DNS is not running because there's no AD....arghhh!!

 

[ncotton]

The AD service, or if you mean the AD machine, should start up regardless of the missing DNS server.

Neil J Cotton
njc Information Systems
Systems Consultant

 

[BCrime]

Here's the mysterious Log entry from the Server:

Eventid 4001
Source DNS

The DNS server was unable to open zone Firma.local in the Active Directory.
This DNS server is configured to obtain and use information from the
directory for this zone and is unable to load the zone without it.
Check that the Active Directory is functioning properly and reload
the zone.
The event data is the error code.

 

[porkchopexpress]

The slow startup problem is refered to as 'The Island Problem', take a look at this doc section 2.16. You shouldn't reboot all DNS servers at the same time.

http://download.microsoft.com/download/c/8/6/c86daf60-cfab-4218-b679-c055d2d6042d/Struct_Plan.doc

 

[porkchopexpress]

But having said that i think if your DNS is AD integrated then it shouldn't really matter. It's worth a read anyway.

 

[porkchopexpress]

Sorry rereading the doc it's the other way around.

 

[porkchopexpress]

Found what i was looking for.

This guy works for MS and this is their recommended AD/DNS setup, it's worth a look and to check that your DNS is configured this way.

faq950-6083

 

[BCrime]

Sounds very good...they speak about to point the first DNS to
the PDC, does this mean that this Config is for AD in mixed mode,is this DNS Config also recommended for Native Mode ?

 

[porkchopexpress]

He is refering to the PDCe which is the first DC installed into the domain and holds the PDCemulator role. This will also typically be your first DNS server as well.

 

[porkchopexpress]

To be honest i've seen a few sites where when all DC's that hold DNS are rebooted at the same time it takes longer than normal. I get it on my DHCP server it starts moaning that it can't see the AD and the AD is waiting for DNS but it's all fine after a few mins.