random ping responses.

Hi I was wondering if anyone has experienced this problem. Please see attachment.

It doesnt matter what I ping or what ever workstation is used, we seems to be getting some unfamilar reponses when pings other workstations, servers etc.

Has anyone had this problem. If so could any one point me in the direction of what it could be.

I thought it might be a problem with DNS but everything seems to be happy on the DNS servers.

a worrying error I am getting in event viewer though is

"Windows cannot obtain the domain controller name for your computer network. (An unexpected network error occurred. ). Group Policy processing aborted." Error 1054.

Any help would be appreciated.

Could be a broadcast storm on the network. Are logons and access to network resources slow?

The negative times are a nice touch ;)

DNS is only likely to be the cause if you are pinging DNS names rather than IP adresses.

Since you have dodgy messages about your DC, run netsiag at the workstation and dcdiag at the DCs, this should point out most problems.

To check for broadcast storms, go into a couple of your switches (assuming that they are managed) and see how much traffic there is - some (e.g. Procurves) will even tell you if a broadcast storm is happening.

Also on a loaded network it could be QoS traffic shaping to blame. Well configured routers and switches prioritise TCP, UDP then finally ICMP traffic. Leading to variable ping times.

Do you have any QoS configured on your network gear?

My gut reaction would be to check for loopbacks on the network.

They tend to trigger broadcast storms and are brutally easy to cause. (simply plug a patch lead into two sockets at the same time)

Another possible cause is if you have port trunking enabled on one side of an uplink, but not on the other.

HP in particular is a favorite for the broadcast storm scenario as they have spanning tree enabled by default. The broadcast storm is caused by spanning tree trying to reconfigure itsself to and getting all confused.

Year 9 at one of our schools had a field day with this when they cottened on how easy it was to have the technicians running round like headless chickens playing find the patch lead.

Solution was to disable spanning tree on all but the uplink ports.

first week we started, the network manager and coordinator were both out, one of the kids decided to patch a network cable into the two ports. Slowly the network grounded to a standstill. Eventually we located the cause. Having examined the documentation of our master switch i enabled spanning tree, but after 6months disabled it was it has an overhead. No one has did the network cable loop since touchwood.

apprantly I been looking into this deeper, and it seems to be a problem with Nforce cards on a AMD x2 64 3000+ processors.

Quote:

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Originally Posted by ranj

apprantly I been looking into this deeper, and it seems to be a problem with Nforce cards on a AMD x2 64 3000+ processors.

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Sure you dont mean with Nforce network cards & AMD CPUs? Or did I miss a huge technology leap? :lol: Sorry.... couldnt resist! :P

You're not using their rubbish hardware firewall thing are you?

i sense compaq presario machines with dodgey firewall program lol disable / uninstall it lol

Theres just no excuse for nforce cards in general - pretty rancid hardware.

If you have some media convertors between switches that can also cause packet loss and you may see symptoms like yours, i would check the patch/fibre leads as well.

Ash.