Add more port to existing etherchannel...port-channel

[the-lebowski]

Hello

I have an etherchannel trunk (3750's) between my two floors.  I have since added another run and would like to add that port to the trunk, what is the correct way to do that?  Add the trunk configuration to the interface before adding it to the channel-group? Or will it gain the same config as the others upon being added to the group?

[danrya]

You should shut down the new port, and configure it exactly like the other port(s) in the port channel.  If there is "ANY" misconfiguration when you add it to the channel it could cause an outage.  After you add the Channel-group command to the port, you can "no shut" to add it to the bundle.

You might want to test the link before adding it to the channel, to ensure there are no physical issues (gbic or cable).  To do that you can add both ends to a VRF and make the interface an L3 port and just ping between them.

You can use this for testing the link

SWITCH1:

ip vrf TEST

interface gig1/0/1

shut

ip vrf forwarding TEST

ip address 10.10.10.1 255.255.255.0

no shut

SWITCH2:

SWITCH1:

ip vrf TEST

interface gig1/0/1

ip vrf forwarding TEST

ip address 10.10.10.2 255.255.255.0

no shut

From switch 1, "ping vrf TEST 10.10.10.2".  After you've tested the link shut the interface back down and remove the config and add it to the channel.

Dan

[Dan-Ciprian Cicioiu]

Best way is to configured as it is the port-channel , and then

add it to the port-channel.

Dan

[the-lebowski]

In the end I add the correct configuration to the new port and shut it down, added it to the port-group with 'chanel-group x on' and then brough it back up.  All is well.