All network traffic STOPS on Domain Controller...?

[LudivousKain]

I'm having a very odd issue here. Im running WinServ2k3Ent in an office environment. It is configured to run as the domain controller, with only one client PC connected (for now, I'm still in the pre-deployment stage). The client PC and DC work beautifully together, but once in a while (and every time I try to send a large file or several large files over the network to the DC), the DC stops responding to any traffic on that network adapter. The workstation is kicked into offline mode, and restarting it only manages to frustrate me, since it then cannot connect to the domain to log in.

When I go to the server itself and try to diagnose the issue, I draw a blank. No event logs, nothing looks out of the ordinary. The only thing that shows me that there is a problem is that the server will hang if I try to disable (or even make changes that require it to be disabled/re-enabled) the domain network adapter on the server, pending a restart.

If I don't try to transfer large files, the DC will remain fine for many many hours, before it falls into the same problem.

This is not my first 2k3 deployment, but this is the first time I have ever experienced this kind of an issue. Below are the server specifications:

Windows 2003 Server Enterprise Edition x86 SP2
Motherboard: TYAN S2881UG2NR
Processor: 2x Dual-Core Opterons
RAM: 8gb DDR400
SCSI Add-In: LSI22320RB-F (Connected to the external RAID subsystem)
Internal HDD: 2x80gb WD Caviar

Edit:
There is also no antivirus software on this, as well as no firewall software running. The firewall is counter-productive since there is no internet connectivity to the domain, and there is a ZyWall between the DC and it's internet connection. Even though there is another firewall on the router the ZyWall is plugged into, I have the ZyWall configured VERY aggresively.

I'm currently using both the onboard NICs, one is enabled/disabled on-demand for downloading things from the internet (OS opdates, software patches, etc), while the other one is always enabled and where the domain PC is connected.

Any assistance with this issue will be MUCH appreciated. I have not tried connecting a new NIC in the server, since it's already in a cabinet and I would have to do considerable heavy-lifting to hoist it out of there.


-Devin

[Monty007]

Hi, I know that ZyWall is configured but for you not to have anti-virus is playing with danger....what if the workstaion becomes infaected it could pass through to your server.
As for you issue this will take a bit of research. Fist I would try is installing another nic. Sorry yes some liffting may be involved)
When the server looses connection can you release/renew the ip without rebooting?
Are you sure there is no hardware updates? Before starting this work create a back up!

[LudivousKain]

-EDIT-
What a complete arse I was, just now. I typed this whole reply and forgot to thank you for your reply so far. THANKS!

Well, after wrestling with the case for a while, I managed to plug in a new NIC card. I disabled the onboard NICs in the BIOS and used just the one D-Link card. Things then went the same as before. It worked nicely for a while, then it suddenly stopped paying attention to any/all traffic on that card. I guess that means that it's not a hardware problem... Joy.

The only thing I can think of is relating to the static DNS rules I have set in place. The way I was able to get it to connect to websites when I enabled the secondary NIC was to specify that DNS in both TCP/IP Properties, in addition to the typical 192.168.0.1 that must be there for all domain controllers to function properly.

Also, I clearly cannot release/renew the IP since it's a DC, and has the IP static.

Yes, I have many MANY backups of the data. This is going to replace an existing system, so data loss won't be catastrophic in this stage, just annoying. I'm also going to set up three separate forms of data backup, two of which will be shipped off-site upon completion.

Now, here's where it gets interesting. Even when I try to do a normal system restart once the NIC stops responding, the server hangs on shutdown and requires physically pressing the reset button. Pinging results in 100% loss once the network stops, also. No outbound nor inbound work on the domain NIC.

-Devin

[Monty007]

Hi, from your last paragraph this is looking like a corruption within the OS.

[LudivousKain]

Sorry for the long delay with the reply. I've come up with a couple of things I can do to test the software aspect of it.

Right now, the only real thing I've configured on the server would be the Active Directory policies. So, what I was thinking about doing was to completely disable every AD policy and transfer a large (2+gig) file to the domain controller to see if it still stops responding.

If so, I will do a complete backup of the DC to removable media and reinstall 2k3. I will then load the same large file on again and see if the NICs shut down again. That will allow me to prove once and for all whether it is indeed hardware failure or software corruption.

Again, thanks for the replies. I'm actually hoping it is something as simple as OS corruption, because I would hate to have to replace this server mobo..

-Devin