Active Directory 2003 Upgrade

[Ryan]

We are currently planning an Active Directory 2003
upgrade. However, we are looking for a fail safe way to
roll back to Active Directory 2000 if there is an issue.
According to MS Knowledge Base article 241594 the schema
can not be authoritatively restore.

Is there a Microsoft approved way to roll back after a
forest and domain prep? Also is there a way to roll back
after the first DC has been updated to Windows 2003?

 

[Chriss3]

The Schema changes can't be rolled back without a complete restore of the
directory, make sure you have a full back up before you do the ad
preparation for the 2003 Schema. Try the preparation in a test domain first.

 

[Ryan]

I thought an authoritative restore was the same as a
complete directory restore. Is there another process for
to complete a directory restore?

We are preforming the upgrade in a test domain, but we
can not completely mirror our live side. So we would
like to be able to roll back if necessary.

Thanks

 

[Paul Bergson]

You could remove a DC from your domain (Hopefully you aren't huge) and if
there are problem you could remove the upgraded DC's from the dc and then
plug-in the dc you removed originally. You would then have to rebuild ALL
the dc's you removed (Just like if you had to do a restore). But all
changes made since the upgrade would be lost, you would have to seize the
FSMO roles, I believe all domain devices (Servers and workstations) would
have to be re-joined to the domain (Their passwords would have changed once
you have migrated to the new o/s). In other words be sure you want to move
forward and unless you have no way to go but back then go back, otherwise
resolve the upgrade issues. The upgrade is pretty aggressive you really
don't want to go back and you shouldn't need to.

 

[LR]

If you follow recomended procedures, the upgrade can be reversed.

1) disconnect schema master from network
2) upgrade schema master to W2K3
3) if successful connect to network.
if failed cease schema master role from another DC and delete the old
schema master from AD, this will role back upgrade.

 

[Enkidu]

No, not exactly. An authoritative restore allows you to restore all or
part of Active Directory. You first go to AD recovery mode and do a
non-authoratative restore and *before* going back online, mark all or
part of the AD as authoratative. This means that the marked parts will
not be overwritten by replication and they will be replicated to other
DCs. An authoratative restore of the whole directory would reinstate
the Schema, I believe, so you are correct in that sense.

If I was doing this task, I'd move everything I could somewhere else,
backup up the system, try the upgrade and if it failed, I would
re-build the machine from scratch, and restore everything.

Cheers,

Cliff