EtherChannel - Configuring on CISCO 4500

[dacruzer1]

Hello Everyone,

I am about to configure 4 Gig ports for EtherChannel.  I've been reading about EtherChannel and it seems easy enough to configure.  I have a host (server)which I am going to connect to these 4 - gig ports.  This is new for me and would like some feedback for those that have used EtherChannel on their layer 2 switches.  Any comments would be very helpful.  BTW.  The gig ports will be an access port with VLAN XX.

THanks

Alfred

[Jan Hrnko]

Hi,

Etherchannel is a great technology and yes you are right - it is simple enough to configure without any bigger problems. As you may know you can connect up to 8 ports into one etherchannel link, the ports just need to be the same speed, duplex mode and they need to match the same allowed vlans(if you are configuring trunk, which I suppose is not your case) or be assigned to the same VLAN (your case). The ports in the etherchannel don't need to be contiguous which is a good thing. I hope you will manage to configure it successfully just in a matter of few minutes. Good luck! If you have any questions, please feel free to ask!

Best regards,

Jan

[dacruzer1]

Hi Jan,

THanks for the info regrading that the ports do not need to be contigous, did not know that.

THanks again,

Alfred

[Jan Hrnko]

Hi,

You're welcome, they even don't need to be on the same module. One more thing : make sure that all ports are up, otherwise it will be considered as a route failure and this port won't be used in etherchannel link.

Best regards,

Jan

[Ven Taylor]

Here's a little more info about EtherChannels that I recently found out:

Apparently, when using the default EtherChannel config, one leg of the channel can be preferred over the others. 

This causes the EtherChannel to read low usage when monitoring, but the individual leg will drop packets due to over utilization.

I originally thought the switches aggregated the legs, which they sorta do, but in truth, individual conversations tend to stay on single legs.

Here’s a link to the Cisco support forums where they show a “workaround” of sorts.

If you ever run into a problem like this, the load-balance command may help out.

https://supportforums.cisco.com/message/527977#527977

Ven

[dacruzer1]

HI Ven,

THanks for that detailed information, this will definitely help me out.

Alfred

[fb_webuser]

config t

int range Gi0/1-4

channel-group 1 mode desirable

and all 4 ports become part of Virtual etherchannel interface called port-channel1 and then configure port-channel 1 interface as trunk.

configure this command on all of those 4 gig ports:

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Posted by WebUser Neeraj Jagga