I had a DR question that I'm pretty confident someone here could
answer for me, and it would be much appreciated!

My company has 3 sites, for the sake of this post I will call them HQ,
DR-Site1, and DR-Site2. Our HQ site has 3 domain controllers, and each
DR-Site has 1 single domain controller. During our DR exercises that
occur twice a year, we sever the connection to our HQ site and rely on
only the DC's and resources that we restore from backup at each of the
DR-Sites.

Because of the large number of server restores we do along with the
fact they are restored to different subnets, we find ourselves making
a lot of changes to DNS records, WINS records, and computer accounts
on the DC's at the DR-Sites.

During these exercises, our HQ site continues normal business and the
domain controllers here remain in production. They complain about no
longer seeing/replicating with the DC's at the DR-Sites, but it does
not impact production resources. At the conclusion of the exercises,
our current method of getting everything back to normal is to perform
metadata cleanup at the HQ site, blow away the DC's at the DR-Sites,
and then rebuild/re-promote those DC's to get them back on the
production network.

While the metadata cleanup process isn't all that tedious, I've been
wondering if another procedure might be less time consuming:

Prior to the start of the DRE, take System State backups of the DC's
at the DR-Sites. At the conclusion of the DRE, rather than metadata
cleanup/rebuilds, couldn't we just use those System State backups and
perform non-authoritative restores on the DR-Site domain controllers?
If I understand correctly, the non-authoritative restores would tell
the DR domain controllers that *their* AD data is incorrect/out-of-
date and to replace it with the data from the production DC's. Is my
logic here correct? Or should I just stick with the current method?
Many thanks in advance!

Re: Win2K3 Domain Controllers - DR Exercises by ctvader

ctvader
Wed Mar 26 11:46:06 PDT 2008

That is how we used to do it when we had DR sites (we now run in an
active/active DC model). We would take a system state backup of our
DC's in the DR site, shutone down one of the DCs just to be safe,
break the links and do our tests (change DNS records, etc). However,
we never seized roles b/c we could take that risk.

When the test was over, we would do a non authoritative restore on the
DC, power the other DC back up and then restore the links. We
operated like that for about 5 years and never had an issue with bad
data on a DC.


Re: Win2K3 Domain Controllers - DR Exercises by David

David
Wed Mar 26 11:54:32 PDT 2008

I appreciate the feedback - we perform no FSMO role seizures during
these exercises, since they only last 48 hours.

I was planning to take System State backups of the DR DC's just before
we break the links to the HQ site for the exercise, and at the
conclusion of the exercise perform the non-authoritative restores on
the DR domain controllers.

One question though - do I perform the non-authoritative restores on
the DR domain controllers BEFORE or AFTER we bring the link back up to
the HQ site?? (thus re-establishing connectivity to the production
environment/DCs)

Re: Win2K3 Domain Controllers - DR Exercises by ctvader

ctvader
Thu Mar 27 12:27:49 PDT 2008

On Mar 26, 2:54=A0pm, David <david.f...@gmail.com> wrote:
> I appreciate the feedback - we perform no FSMO role seizures during
> these exercises, since they only last 48 hours.
>
> I was planning to take System State backups of the DR DC's just before
> we break the links to the HQ site for the exercise, and at the
> conclusion of the exercise perform the non-authoritative restores on
> the DR domain controllers.
>
> One question though - do I perform the non-authoritative restores on
> the DR domain controllers BEFORE or AFTER we bring the link back up to
> the HQ site?? (thus re-establishing connectivity to the production
> environment/DCs)

You want to do the restore before you bring the links back up - this
is a must. Like I said earlier - it worked pretty well for us but we
never seized roles as our testes only last a business day.

Re: Win2K3 Domain Controllers - DR Exercises by David

David
Thu Mar 27 13:08:13 PDT 2008

The domain controllers at our DR sites do NOT hold any FSMO roles. All
of the roles for the forest are held by domain controllers in our HQ
site only. So it sounds like our scenario is very much like yours