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New Member

Cat 2924 Etherchannel Problem

Hi All

I have a Cat 2924 switch that I'm trying to connect to a cat 5500 switch via an etherchannel (ISL trunk). This, however, works better on paper than in real life...

I get HUGE amounts of errors (CRCs) in the two ports on the 2924 that I'm using, but none on the 5500. I am using ports 1 & 2 on blade number 4 out of 12 on the 5500 ( Model: WS-X5225R, Hw :3.3, Fw : 4.3(1)), and ports 1 & 2 on the 2924 (IOS ver 12.1).

Also, the LEDs on the etherchannel ports on the 2924 alternates between green and amber all the time.

Both sides are nailed at 100Mbps full duplex.

When I dissolve the etherchannel, the errors disappear, but the trunk port's LED still alternates between green and amber.

Performance is also not what it should be. Most of the time all the port LEDs flash simultanously, which leads me to believe that there is excessive broadcasts?

Any ideas on how to rectify this situation?

New Member

Re: Cat 2924 Etherchannel Problem

If you are trunking, you need to use the "nonegotiate" mode in the 5500 since the XLs don't negotiate and the DTP (negotiation packets) are counted as CRCs on the XLs. Amber LED indicates that the port may be in blocking. Make sure you use "on" for port channel.

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