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Cisco Gig Switch and 3Com Gig Switch

One of my techs connected a Cisco 3650 Gig swtich to a 3Com Gig switch I think they may have used a crossover cable. The problem is that I connected a client on the 3560 switch and tried to ping a server on the opposite end the response times were 2 of 4 (replies) or 1 out of 4 four. Then I did a continous ping and the response times were successful reply and failure, succesful reply and failure. I am sure this means that the interface is flapping for some reason. The Cisco switch port is configured Spanning tree protocol usase but the the 3Com is not. Should I turn this off on the Cisco switch or should I turn it on, on the 3Com switch, or is there something else I need to do. This inconsistent connection is driving me insane. Please help, thanks!


Re: Cisco Gig Switch and 3Com Gig Switch

I have seen issue between cisco and 3com gig conection related to auto negotiation of the flow control. This setting is best turned to off. Flow control only makes since to a server since switches are suppose to switch at wirespeed nowdays.

Unless you have a dual connection between the switches it does not mater if you have spanning tree on or not. A spanning tree loop in general will not just cause some packets to be lost it normally cascades into a total outage until it is unplugged.

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Re: Cisco Gig Switch and 3Com Gig Switch

So can you possible tell what these symptoms maybe?? I not sure where to look and this causing my brain to hurt thanks.

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