DC recovery using a stale clone.

Good Day,

I am new to the SAN game and have been mulling over the implications of
Clones of a DC. We thought that it might be a good idea to clone our DCs at
strategic points in our network life cycle as a disaster recovery technique.

Then I began to wonder, "What happens in AD if I bring online a clone?" My
worries are that the clone will be "DC minus a month" of AD changes. How are
the other DCs going to react to this server appearing and claiming to be
DC-X, except that DC-X has had amnesia for the last month?

Any thoughts would be appreciated.

Hello David,

Clones are a not supported AD aware backup solution. See here about the reason:
http://support.microsoft.com/kb/875495/en-us

Here is the supported way to backup AD:
http://technet.microsoft.com/en-us/l...72(WS.10).aspx

Best regards

Meinolf Weber
Disclaimer: This posting is provided "AS IS" with no warranties, and confers
no rights.
** Please do NOT email, only reply to Newsgroups
** HELP us help YOU!!! http://www.blakjak.demon.co.uk/mul_crss.htm


> Good Day,
>
> I am new to the SAN game and have been mulling over the implications
> of Clones of a DC. We thought that it might be a good idea to clone
> our DCs at strategic points in our network life cycle as a disaster
> recovery technique.
>
> Then I began to wonder, "What happens in AD if I bring online a
> clone?" My worries are that the clone will be "DC minus a month" of
> AD changes. How are the other DCs going to react to this server
> appearing and claiming to be DC-X, except that DC-X has had amnesia
> for the last month?
>
> Any thoughts would be appreciated.
>

Howdie!

Am 31.05.2010 15:49, schrieb David:
> Then I began to wonder, "What happens in AD if I bring online a clone?" My
> worries are that the clone will be "DC minus a month" of AD changes. How are
> the other DCs going to react to this server appearing and claiming to be
> DC-X, except that DC-X has had amnesia for the last month?

Don't do that -- not worth the hassle and not supported. Stick with
"normal" backup/restore means and you'll be happy.

Cheers,
Florian

Meinolf,

Thank you. 875495 did indeed provide a plethora of reasons not to do what I
was thinking about.

I have yet to read the second article, but will tomorrow.

Thank you!

"Meinolf Weber [MVP-DS]" wrote:

> Hello David,
>
> Clones are a not supported AD aware backup solution. See here about the reason:
> http://support.microsoft.com/kb/875495/en-us
>
> Here is the supported way to backup AD:
> http://technet.microsoft.com/en-us/l...72(WS.10).aspx
>
> Best regards
>
> Meinolf Weber
> Disclaimer: This posting is provided "AS IS" with no warranties, and confers
> no rights.
> ** Please do NOT email, only reply to Newsgroups
> ** HELP us help YOU!!! http://www.blakjak.demon.co.uk/mul_crss.htm
>
>
> > Good Day,
> >
> > I am new to the SAN game and have been mulling over the implications
> > of Clones of a DC. We thought that it might be a good idea to clone
> > our DCs at strategic points in our network life cycle as a disaster
> > recovery technique.
> >
> > Then I began to wonder, "What happens in AD if I bring online a
> > clone?" My worries are that the clone will be "DC minus a month" of
> > AD changes. How are the other DCs going to react to this server
> > appearing and claiming to be DC-X, except that DC-X has had amnesia
> > for the last month?
> >
> > Any thoughts would be appreciated.
> >
>
>
> .
>

Florian,

Thank you for your response. It appears that you agree in spirit if not
detail with the first article mentioned by Meinolf.

Thanks.

"Florian Frommherz [MVP]" wrote:

> Howdie!
>
> Am 31.05.2010 15:49, schrieb David:
> > Then I began to wonder, "What happens in AD if I bring online a clone?" My
> > worries are that the clone will be "DC minus a month" of AD changes. How are
> > the other DCs going to react to this server appearing and claiming to be
> > DC-X, except that DC-X has had amnesia for the last month?
>
> Don't do that -- not worth the hassle and not supported. Stick with
> "normal" backup/restore means and you'll be happy.
>
> Cheers,
> Florian
> .
>

Cloning/imaging a DC is not a good thing. First off, there is a thing
called the "Tombstone" period (default of 60 days). If you exceed that
it would be a disaster to restore the image.

Best idea is to have multiple DC's with integrated DNS and split DHCP
scopes. Make each a GC. This way, if one fails, the others will pick up
the slack until you can rebuild or restore the hardware.

I would also recommend you have backups of:

- System State
- DHCP
- any other functions that the DC may have.


Regards,
Hank Arnold
Microsoft MVP
Windows Server - Directory Services
http://it.toolbox.com/blogs/personal-pc-assistant/

On 5/31/2010 9:49 AM, David wrote:
> Good Day,
>
> I am new to the SAN game and have been mulling over the implications of
> Clones of a DC. We thought that it might be a good idea to clone our DCs at
> strategic points in our network life cycle as a disaster recovery technique.
>
> Then I began to wonder, "What happens in AD if I bring online a clone?" My
> worries are that the clone will be "DC minus a month" of AD changes. How are
> the other DCs going to react to this server appearing and claiming to be
> DC-X, except that DC-X has had amnesia for the last month?
>
> Any thoughts would be appreciated.

Check out an article I have written on clone recovery at:
http://www.pbbergs.com/windows/articles.htm
Select Restoring a Virtual DC from a Snapshot

--
Paul Bergson
MVP - Directory Services
MCITP - Enterprise Administrator
MCTS, MCT, MCSE, MCSA, MCP, Security +, BS CSci
2008, Vista, 2003, 2000 (Early Achiever), NT4
Microsoft's Thrive IT Pro of the Month - June 2009

http://www.pbbergs.com Twitter - @pbbergs

Please no e-mails, any questions should be posted in the NewGroups. This
posting is provided "AS IS" with no warranties and confers no rights.
"David" <> wrote in message
news498F0A4-DC88-41FE-A75D-...
> Good Day,
>
> I am new to the SAN game and have been mulling over the implications of
> Clones of a DC. We thought that it might be a good idea to clone our DCs
> at
> strategic points in our network life cycle as a disaster recovery
> technique.
>
> Then I began to wonder, "What happens in AD if I bring online a clone?"
> My
> worries are that the clone will be "DC minus a month" of AD changes. How
> are
> the other DCs going to react to this server appearing and claiming to be
> DC-X, except that DC-X has had amnesia for the last month?
>
> Any thoughts would be appreciated.