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Late collision detected?


I have late collision detected over at my Ethernet’s 800 series router interface. How can I resolve this by avoiding to shutdown each computer in the LAN segment? Is there any software that can detect which NIC is the culprit?



Re: Late collision detected?

What is your 800 router ethernet connected to? If it's a switch hard-code the speed and duplex to 10 half. If you have other devices connected to the hub-ports on the 800 then perhaps one of them didn't auto-neg. speed / duplex correctly.

Software wise, a sniffer might be able to detect this providing it can use your NIC and the NIC doesn't filter out physical layer errors like these. Most NICs don't pass these up to the OS. Best method would be take PCs off the network one by one until you find the culprit.

New Member

Re: Late collision detected?

Thanks eber.

The router is connected to a HP AdvanceStack 10Base T hub. All devices connected to the hub are client pcs and a print server. Speed/ duplex error is a possibility.

But I suspect the problem is with a faulty NIC. Majority of the pcs in this LAN are old units. I was hoping there could be a miracle software to assist me in locating the faulty NIC. I suppose this is not the case since you mentioned most NIC not able to pass late collision error to OS... read something about that in Ethereal's documentation.

Thanks again.

New Member

Re: Late collision detected?

Since you are using a hub it would be wise to check your cable lengts because a late collision is a collision occurring later in the frame than it should. Otherwise will other delay introducing componenets be a possible explenation for your problem.

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