Cat2950 to Cisco 1601/ 3620 autonegotiation

[lincoln.brant]

I have recently "inherited" a legacy network with 1601 and 3620 routers connecting to a Catalyst 2950 switch. On both switch interfaces i am seeing high levels of input errors, collisions and deferred packets indicating a duplex mismatch. I have hard coded the switch ports to 10full 10half and back to auto and still see various combinations of the above errors on both the switch ports and the routers ethernet ports. Has anyone experienced anything similar?

[Georg Pauwen]

Hello Lincoln,

I think the 10MB ports on the 1600 and 3620 routers do not support full duplex operation. At least make sure that you hardcode everything to half duplex and 10MB, in order to minimize the amount of errors. Collisions and input errors will remain, since they are part of how (half duplex) Ethernet works.

If possible, try to upgrade to a platform that supports FastEthernet (the 1601 does not support it), or get FastEthernet modules for the 3620...

HTH,

GP

[lincoln.brant]

GP, thanks for that, I was just suspicious about the numbers I was seeing. Been a while since I've dealt with Half Duplex anything, apart from bad negotiations with Unix boxes.

Lincoln