Trouble with etherchannels on 2950 switch.

[Oliver42]

Hi, 

I did a simulation of a network in PT recently and now that I'm working on the real thing with real devices I'm running into a few problems.

As you can see from the picture below the two 2950 switches both have two etherchannels. I configured one on each at first and everything was fine. Then I configured the second one (port-channel 3) and when I connected my ethernet cables to the ports on the switches nothing happened, they stayed down. I then looked at the running-config to find out that my port-channel 3 stated ''flowcontrol send off''.

What does that mean? I've never seen that before.

    

[MHM Cisco World]

Etherchannel  port must identically, but here one is support flowcontrol other not,

So config flowcontrol.

This command is not shown in run-config, but is shown in show interface 

[Oliver42]

I'll do some research, but I never had to configure flowcontrol. How do I do it?

[Giuseppe Larosa]

Hello @Oliver42 ,

flow control off is not a reason for ports to stay down.

I remember that Catalyst2950 had several limitations when dealing with port channels.

In some models only one port of a bundle stayed up and the other one was used as backup.

Post

show version

show etherchannel summary

Hope to help

Giuseppe

[paul driver]

Hwllo

sh etherchannel summary

sh etherchannel port-channel 

sh spanning-tree blocked ports 

[MHM Cisco World]

http://www.cisco.com/en/US/docs/switches/lan/catalyst2960/software/release/12.2_58_se/configuration/guide/swint.html#wp2071785