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New Member

About Etherchannel


I want to connect 6509-E switch with 3750-stack which is now in production network.

so, I want to know that is it possible to create a Ether-channel between the 2 switches without disturbing the production on 3750 switch.
I want create this Ether-channel for testing purpose.

so can I create a vlan on both switches than I will make Ether channel ports isolated so that it will not effect the production network if the testing of this Ether-channel works than I will deploy 6509 switch in my production network?

I am making these ports Isolated so that it will not effect the production network due to spanning-tree convergence. 

I want to know that this Ether-channel verification will work or not ?

OR can I create a Ether-channel on the same switch i.e. from 6509 to 6509 for testing purpose.

If their is any other method than revert me back


Rahul Chhabra
Network Engineer
Spooster IT services 

Hall of Fame Super Gold

Depends on a lot of factors,

Depends on a lot of factors, like IOS, the steps you're going to do to implement this, etc. 


If you don't know what you're doing, you will have to plan outage.  


I've enabled Etherchannels on the "fly" (in production) and the most I get is a few ping drops.  

New Member

Thanks for respondingthese

Thanks for responding

these are few steps I am going to implement:

3750 is our core stack connected to another 5 switches with many servers so my task is to replace this core with 6509-E VSS. I want to decrease the downtime when I was replacing the core.

My plan is to create ether-channel between 6509 and 3750 and also removing the config from 3750 and pasting the same config on 6509 so that my traffic start moving trough 3750 than 6509 and on ISP.

so to deploy this I am creating this ether-channel but not sure what is the effect of that ether-channel on the network that it will come up or not because it is a Multi-chassis Ether-channel from 6509 side and cross-stack ether-channel from 3750 side. 

Rahul Chhabra
Network Engineer
Spooster IT services


Hall of Fame Super Gold

It can be done.  Like I've

It can be done.  Like I've said, I've done it to a live production environment.  It's just a question of the "steps" to put your configuration and how the physical layer is set up.  


Let's say you have two links running between the two.  Let's say your 6500 is your core switch.  I'm going to call your 6500 as the "local" switch and the 3750 as the "remote" switch.  


Here's how I would to things:  

1.  Disable the second interface from your core switch (this prevent loop) before connecting the second link. 

2.  Enable the ether-channel on the remote switch with the following commands: 

conf t

interface range Gi <BLAH> - <BLAH>

channel-group <NUMBER> mode <BLAH>

3.  Enable ether-channel on the local switch.  

conf t

interface range Gi <BLAH> - <BLAH>

channel-group <NUMBER> mode <BLAH>

no shutdown