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4840G to Cat5505 over Gigabit Trunk; Port-Channel/BVI???

I am trying to configure a 4840G to talk to two Cat5505's over gigabit ethernet. Both the 4840G and the Cat5505's have two Gigabit interfaces with the two Cats already talking to each other over gigabit interface setup as a trunked link. (Both Cat's have SEngII and one has an RSFC on board)

I have tried getting the 4840G to talk to the Cat5505 by setting up a port-channel interface which includes the two gigabit interfaces, however the port channel will not let me config ISL enacapsualtion (IOS doesn't recognise the encapsulation command, which is contrary to the documentary on CCO) and will not pass traffic. Am I doing something glarying wrong, or has anyone got any experience in configuring a 4840G to use the gigabit interfaces as both a management interface and a trunk link for ISL Vlan routing. Is there another way I should setup the 4840G to talk to the Cat's via the gigabit interfaces?



Re: 4840G to Cat5505 over Gigabit Trunk; Port-Channel/BVI???

All interfaces will not support all the encapasulation types, check the port capabilities and see if ISL is support on those interfaces? I am also not sure about using the management interface for a trunk link.