Hi everybody. Please I'd like you to help me understand what's happening in my network. Maybe some of you have suffered a similar problem. I detected this morning very slow ping response from the router. There's aprox. sixty computers in my network and the response comes normally in <10ms, which is ok. This morning I got between 500ms and 1s. Looking at the trunk switch I could see one port was blinking wildly, while the other had a normal blinking. So I followed that port trhough the network and found a PC that, if I turned it off, the router ping response was again <10ms. That PC is causing all the network problem, or it is what it seems. I'm trying to understand what kind of problem in a single PC can make all the network suffer. Could it be a virus? Maybe a misconfigured network card? And, the most important thing: how can I avoid that one PC can slow down an entire network? Many thanks in advance, Rafael

The simple answer is "Yes" You say what sort of hardware is involved but I had an identical problem with a 3C509 NIC. I removed and replaced the driver to no effect so I removed the NIC and threw it in the bin and installed another, fixed! If you have a machine with an inbuilt NIC it's worth disabling it in the BIOS and inserting a discrete NIC and try, I've had that on a Compaq D510 once. Hope this helps. Regards, Bob. That is the biggest fool thing we have ever done. The Atomic bomb will never go off, and I speak as an expert in explosives. - Admiral William Leahy

What I would do, before doing anything else, is check what is going on with the NIC of the PC in question. You can use the built in Performance Monitor (in Administrative Tools) to run some checks on the NIC. Also, you could use a network analyzer (like Ethereal) to see just what kinds of packets are being transmitted. It's not likely to be a virus or anything like that. If the NIC is bad and creating a "broadcast storm" of broadcast or multicast traffic that would cause problems.

As above two posts but include an ethereal sweep to see what is going on.