Network issues after DC hardware failure....

[Little-Miss]

My friend is struggling after the main board of their school DC failed....

 

She requests the help of the collective Edugeek brain...

 

Following a main board failure on our domain controller and replacing the board since then we have had a number of issues.

 

1. when an IP lease expires the network adaptor crashes on the machine and the only way of fixing it seems to be by resetting it through command prompt.

2. not sure if this is related but although we have access to local resources the internet is inaccessible.

 

We do have quite a few other issues but these two are the worst. Any assistance would be gratefully received

 

GO!

Edited February 7, 2013 by Little-Miss

[SYNACK]

IP lease on the clients?

What software do they use, onsite filtering, routers etc. For the internet stuff.

 

Depending on the other faults they may help provide more clues to the cause.

[FN-GM]

Have they given the NIC on the server the same IP?

 

Thanks

[serendipity]

The NIC on the server has the same IP yes

[serendipity]

the clients are XP

[Little-Miss]

*bump*

@serendipity...start from the beginning. When you were waiting for the new board you.....

[serendipity]

Sorry not to good on the whole explanation thing,

 

...we had to switch the DHCP role from the dead DC to the other DC. We restored the our redirected desktop and start menus from a backup, to the second DC and corrected the GPOs to redirect to the second DC. Once the broken DC had been nursed back to health, the DHCP role was disabled on the second DC in favour of the original DC.

 

We then started to have clients refuse to log in, claiming the net logon service was not running. Resetting the netsh winSock corrected this, but each time the DHCP lease expired, the network interface crashes and needs to be reset.

 

In addition to this, sporadically PCs cant access the internet (DNS issue?) and GPOs and net logon scripts are not being run or correctly adhered to. Staff are getting the wrong redirected desktop for example, despite the GPOs being correct.

 

Also... when opening the Group policy management console on the formerly dead DC, were now presented with "The specified domain either does not exist or can not be contacted", which we can only assume is not good.

[Domino]

What kind of switches have you got? any way of clearing the ARP cache?

 

Which DC thinks it has the FSMO roles? and is replication working between them now?

[Michael]

The motherboard that's been replaced, is it 'like for like' or a slightly different model? And depending on the first answer, have you performed a full system restore of your Windows OS? The fact you only have the one DC means it doesn't need to be authorative.

 

I'd certainly recommend updating your NIC drivers to the latest available if you haven't done so already.

[Michael]

Re-reading the explanation, I'm guessing the DC that went down had the FSMO roles. To be honest though this shouldn't be the immediate issue. A network can run without a role holder for quite some time.

 

The 'new DC' as I'll refer to it. Did you allocate it the same servername and IP, then perform a full authorative restore (seeing as you have another DC)?

 

If you trying pinging your new DC (by its name, such as CURRICSVR), it should display the right IP. Looking at DNS and DHCP Server should also give you clues as to what's happening.

[CHR1S]

I think we should be exploring the transfer of DC roles to the other server while the main server was down.

 

1) Was the other DC already in the domain with a server role?

2) Did you just install the DHCP role and assign a scope?

3) Did the second DC have DNS installed?

[pete]

As part of the troubleshooting, launch an elevated command prompt on the DC and type:

 

dcdiag /q

 

and post the (redacted, if necessary) output in

 code tags 

(or hand it to @littleMiss for her to go through).

 

you'll probably have to seize FSMO roles on the DC that didn't die. Were both DCs global catalogues?

[Michael]

Any update on this? Give her a nudge Little-Miss

[Little-Miss]

Will do...