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New Member

Trunk Port

In what condition that we must use trunk port? Normally, trunk port is configured under fastethernet port or gigabitethernet port? I see some people use fastethernet port connect to gigabitethernet port. What is the reason for doing that?


Re: Trunk Port

Trunks are used to connect switches when you want hosts on a single vlan spanning across multiple switches to communicate with each other. They can be configured on any ports but duplex, speed, & encapsulation must match on both ends of trunk.

New Member

Re: Trunk Port

I saw some of them do not use trunk port. They just configure the same vlan name on both of the ethernet port on different switch and use cross cable to connect to each other. why?

Whether can use gigabitethernet port to connect each other for both of the switches?

New Member

Re: Trunk Port

Not sure why those people were doing that other than they only wanted one vlan trunking across the ports, but then that defeats the whole purpose of trunking huh? Trunking as we know aallows multiple vlans to traverse uplinks (when configured properly). On switch uplinks you want to trunk, thus carry all vlans accross do the following on either interface of the connected switches.


switch#config t

switch(config)#interface (type/number)


switch(config)#switchport trunk encap dot1q

switch(config)#switchport mode trunk

switch(config)#ctrl z - to exit