Etherchannel question

i need some information on etherchannel
if i have 2 switches A and B
and 2 links from both the switch are needed to be connected for forming etherchannel
is it necessory that i should use same ports(number) on both switch to form etherchannel or i can
use different ports on A and B then form etherchannel

Hello Prateek,

You don’t have to use the same port numbers, you can use whatever port numbers on both sides that you want.


Hi Rene,
Could you please explain PagP silent and non-silent mode with some examples?

Hello Selim

You can find a detailed explanation of these two modes at the following Cisco Support Community post:

You can also see this in the explanation of the channel-group command when configured as either auto or desirable. You can enable or disable non-silent mode only when auto or desirable have been configured:

I hope this has been helpful!


the non-silent mode is the default behavior of the pagp.

first of all cisco themselves don’t recommend to use pagp, only LACP (802.3ad)

the silent mode is used to form etherchannel between a device like pc for trafic analyzing , an dthe pc doesn’t support pagp, therefore there won’t be any pagp adjacency and the etherchannel won’t form.

the silent mode let the switch create the etherchannel as long as the ports confogured and same and he doesn’t care if he get pagp messages or not - it still will create those ports as an etherchannel and it kinda works like the “on” mode without taking risks for the switch to be missconfigured