Could someone clarify the best practice to use when adding VLANS to Etherchannel connections on a pair of Cisco 6500 switch-routers running IOS.
Although the configuration shows the existing VLANS on any physical ports bound to the Etherchannel as well as the Etherchannel itself I understand that you should only add any new VLANS to the Portchannel using the switchport trunk allowed vlan add command and not add the VLANS to the physical ports bound to the Etherchannel as the configuration will add these automatically.
However during the change one side of the Etherchannel will have the new VLANS and one will not, until the VLANS are added to the second switch connected to the other side of the Etherchannel. Does this cause any instability on the Etherchannel? Would it be best to leave the new VLANS in a shutdown state until the Etherchannel VLAN additions have been made?
I need to implement this change without causing the Etherchannel to go down.
Would appreciate any advice.