Global Catalog reconstruction

[vhato]

Anyone know how to recreate the Global Catalog??? My Domain Controller crashed so I promoted one of the many BDC, but I keep getting a damn message about a GC cannot be found when adding new users.

Anyone??

 

[Santa]

Go to your active directory Sites and Services tool.

Then select the server that is down and do a properties on the NTDS settings.

Uncheck that it is a Global Catalog.

Then go to the server you just created or the one you want to make a Global Catalog and then go through the same steps as above except check mark the Global Catalog box.

 

[Saltin]

There's are many other roles that will need to be re-created as well (the five FSMO roles).

It's not a terribly difficult procedure, but if you cant restore the forest root DC, you will have to "sieze" the FSMO roles rather than transfer them. Seizing is a little more hair-raising.

Here

 

[err]

Go to your active directory Sites and Services tool.

Then select the server that is down and do a properties on the NTDS settings.

Uncheck that it is a Global Catalog.

Then go to the server you just created or the one you want to make a Global Catalog and then go through the same steps as above except check mark the Global Catalog box.

I don't think this will work if the only DC in the domain crashed. Promoting your BDC (assuming NT4 server) and letting it have the GC role (steps provided by Santa) won't let it have the original GC as there is nothing to replicate with. In this case, you will indefinitely lose your GC data.

I hope your "BDC" is Win2K server with GC replication enabled. This way it is much easier to restore the GC.

Yes you'll need to seize the FSMO role if your "BDC" is indeed Win2K server.

Hope this helps. And hopefully you have Win2K BDC

eRr

 

[vhato]

Yes all 11 servers are Win2k. I know in Win2k there are no PDC's or BDC's, just a way of describing them. THanks for the assitance. Any other tips are appreciated. I reviewed the Microsoft info and I will seize the FSMO roles.

Thank you
V

 

[Vegito]

all ur dc should be running global catalogs.. it makes thing faster.

 

[Santa]

Whoa whoa.. Make sure which DC died and which roles it had. Don't blindly go seizing roles or you could really muck up the network.

If it was the main server hosting all the roles then yes you need to seize them all but find out what the dead server hosted before you start turning the roles over to a new server.

 

[vhato]

Thanks for all the replies. I really appreciate it. I printed Article Q255504 and plan on doing it. How can determine which roles were used by the dead server??? I found out over the weekend from the technician that discovered the downed server that it actually didn't go down. Due to a little technical "oversite" (screw up) he told the server it was the last server on the network while removing Active Directory to disjoin it. He thought he was on a different server.

He then resetup Active Directory and rejoined the Domain. And because of this I cannot find the GC. Does this shed a little light on the topic for everyone???

Thanks for any more help. If I don't see any replies by Friday then I am going to continue on with Article Q255504's instructions for seizing roles.

Thanks again,
V

 

[Saltin]

all ur dc should be running global catalogs.. it makes thing faster.

That's not correct at all.

The Global Catalog contains a partial record for *every* object in the Forest, hence, replication traffic between GC's can be quite high.

There are certain situations where you would definetly want to have more than one GC (redundancy, multiple sites, etc), but to suggest that all DC's should hold a GC role is laughable.

 

[Santa]

http://support.microsoft.com/?kbid=234790#2

Tells you how to determine the rolls.

 

[stash]

The Global Catalog contains a partial record for *every* object in the Forest, hence, replication traffic between GC's can be quite high

This is correct, but if there is only one domain in the AD, it is safe to make every DC a global catalog server, including the server holding the infrastructure FSMO, which is a big no-no if you have a multiple domain forest.

 

[Saltin]

Stash,

Im not talking about wether it is safe or not. It's not dangerous.

But it certainly isnt necessary. If having more than 2 in a single domain setting is counterproductive.

 

[err]

well, IMO, you should have at least 2 GC in one site. I definitely wouldn't see how all DC should be a GC if everything is in 1 site.

I would definitely seperate the schema master, PDC emulator, operations master and the GC if you have multiple DC in your sites.

eRr

 

[stash]

Making all DCs into GCs in a single domain AD may not be a productive thing to do, but the point is that doing so will not slow down the domain controllers. The speed costs of making a single-domain global catalog are negligible. However, they will not make things faster, as forcesho suggested.

 

[Saltin]

However, they will not make things faster, as forcesho suggested.

That was sort of my point.........

I'm not speaking about slowing computer performance either, I am talking about excess replication traffic on the network that just isnt necessary cost vs benifit.

 

[stash]

This is kind of OT:

I don't work with exchange much, but wasn't there a bug which required a single-domain active directory to have all DCs as GCs for exchange 2000 to work? I seem to remember seeing that soon after exchange 2000 came out, and since it's on SP3 now, I assume it's been fixed, but I'm just curious.

 

[Saltin]

Stash,

If the connection between Exchange 2000 and the GC is interrupted, routing operations and many other essential functions stop dead. In particular I think you are speaking about the following

The MTA to shuts down if Exchange loses contact with a GC. The logic behind this is to stop processing to eliminate the possibility of losing any messages. Unfortunately, sometimes the MTA doesn't (didnt) shut down cleanly and it hangs (hung). The only resolution is (was) to reboot the server--certainly not an optimal process in a situation in which the GC might come back online after a temporary network problem.

This was fixed some time ago... I daresay SP2

Also, Outlook clients depend on GCs for access to the Global Adress List (GAL), so if they can't contact a GC, clients can't validate addresses in email headers, browse the GAL, or check properties of other users or distribution groups. Indeed, the sudden disappearance of a GC affects any client currently connected to that GC and forces users to restart their client.

This is still a fact of life, and I can replicate it again and again. This reason alone is a good enough argument for redundant GC's..... but I'd still have the opinion that every DC holding a GC is overkill and counterproductive.....

 

[vhato]

I wanted to thank all of you that replied to this thread for your help. Worked like a champ and couldn't have done it without ya'll.
Thanks,
V