PDC broken - URGENT HELP NEEDED

[deliamay]

While I was away on my christmas break, the PDC of our NT4 domain crashed and will not re-start -it seems to be a hardware failure and we will need a new server.
We now have in the domain one BDC and 2 other member servers - since the crash, users can log on ok and access the data on the BDC but cannot access data on the other 2 servers.
I think i need to promote the BDC to PDC (could someone confirm this - is it essential ?) and then need to get a new BDC. From what i have read, it seems that you can't promote an ordinary server to be a BDC, but that we will have to get a new server and install it as a BDC. Or is it possible to make one of the other servers become a BDC?
many thanks

 

[NortonES2]

Promote the BDC to a PDC, you can't make a member server a BDC it has to be installed from scratch.

-------------------------------

If it doesn't leak oil it must be empty!!

 

[Koonan]

There is a 3rd-part utility out there that will do what you want, but it's not free. I would just install it from scratch if I were you. Why your users can't access other servers is odd, and shouldn't be related to the PDC being down.

http://utools.com/UPromote.asp

 

[deliamay]

Thankyou NortonES2 and Koonan for your amazingly quick replies. Do you mean Koonan, that when the BDC took over after the crash, it should have transparently taken over the functionality of the PDC completely ? In fact what happens now is that if i try to access the either of the other servers, it asks me for a network user name and password but will not accept any of those in current use!
Now i fear that promoting the BDC to PDC may not solve the problem - should i do it anyway and risk losing access to the data on the BDC ? (all the department's documents!)

 

[deliamay]

One more question before i promote. Do i need to get all of the users out first? In fact i just tried to promote and got the message "promoting will also close client connections to (the BDC name)" - does this mean the users need to save any documents and exit before i promote ?
thanks

 

[deliamay]

Well, i have promoted the bdc to pdc but I still can't see the other two servers. If i try to access them from the new PDC i get access denied and if i try to connect them to another PC it asks me for usernames and passwords, none of which work.
Opening server manager on these two serveres i see options like 'add to domain', 'remove from domain', 'select domain' - should i try any of these ?
After the promotion and a resynch i looked at event viewer and it's full of messages like this: the computer (name) tried to connect to (new PDC name) using the trust relationship established by the (domain name)domain however the computer lost the correct security identifier (SID) when the domain was reconfigured. Reestablish the trust relationship. I have no idea how to do this and would really appreciate any help here. thanks. (i will in the meantime try to find out more on this)

 

[Serbtastic]

Are you sure your other 2 servers were member servers in the same domain, and not PDC/BDCs in another domain?

 

[deliamay]

yes, there's only one domain.
also, if i go into either of the 2 member servers, i can see the pdc and also other pc's on the network.

 

[AndrewTait]

Perhaps the best way of doing this, is to remove the member servers from the domain and re-add them to the domain.

This way it will establish domain membership with the new domain controller.

It sounds as though you have a corrupt server catalogue on one of the domain controllers (I suspect the now defunct PDC) which means it has not replicated these member server credentials to your BDC.

So often times it happens that we live our lives in chains
And we never even know we have the key

 

[deliamay]

Thanks Andrew, i'll try it. I hope it's a straightforward procedure, not having done anything of the kind before ! (i sort of inherited a network - what fun!) I'll do some reading first.

 

[deliamay]

Could anyone explain to me the difference between a member server and a stand-alone server? If i look at server manager, view servers, i can see the 2 'offending' servers but with the "show domain members only", i cannot see them -if i select "add to domain" i get the essage "only windows NT computers that participate in domain security should be added to the domain" - doesn't this imply pdcs or bdcs only (though you have to select between winods NT workstation or server and BDC as computer type).
I cannot seem to find an article which explains these things. Thanks

 

[Spirit]

This is what MS has to say;

http://support.microsoft.com/kb/126436/en-us

Basically a Member server is part of the domain with all the centrallisd admin that goes with it while a Standalone does exactly that, stands alone so you need to do any admin locally as it is not part of the domain.

Iain

 

[MrRetro]

I would look at nbtstat, perhaps clearing the cache etc...I had a similar problem with a remote site losing its domain connectivity when we switched IP schemes, this fixed it. I don't believe you will need to (or should) remove them from the domain.

 

[deliamay]

Thanks - just as i was about to delete them from the domain and add them again ! Do i need to run nbtstat on the PDC or on the 'offending' server ? and which parameter R or RR ?

 

[MrRetro]

Run it on the PDC using the -RR see how that works for you...to be honest when I had this problem I think I ultimately ran every switch with the command, but I think the RR one is what did it. When I had this problem Server manager always had the machine show up a a server but I couldnt access it until I had run that nbtstat stuff.

 

[deliamay]

thanks again - do you think it's a fairly safe procedure to try (am i likely to make the problem worse ?)

 

[MrRetro]

Definately wont make it worse running that command. Hopefully it will fix your problem.

 

[deliamay]

Well, i just ran nbtstat -RR on the PDC do i need to restart the PDC, the other server or both ? it does seem to have worked so far. thanks for your patience.

 

[deliamay]

oops, i meant to write DOESN'T seem to have worked so far. i restarted the other server (not the pdc - there are too many files open at the moment) but i still get the same message - no domain controller, even though i can ping the PDC from this server and see the rest of the network.

 

[MrRetro]

Shouldnt need any restarts for this to kick in...is your wins on the PDC ? Try the -c flag to see what the pdc has cached for nbtstat.