STP Question

Netstudent

Boson says that when a port is forwarding and then a new root bridge is elected, if that port is going to be forwarding after the re-election, then it will never change states.

I don't recall reading this so I was wondering if it was true. Does anyone know a good article or perhaps a place in the books that I could have missed that states this? I have sybex delux and ciscopress ICND.
Thanks

borumas

Hmm, I thought that when a new root bridge is being elected Configuration BPDU's are passed out and it goes through a listening and learning state, taking connectivity down for 30 seconds or so.

EdTheLad

A forwarding port will only go into blocking state when a superior bpdu is received on another port on the local switch/bridge.Since a superior bpdu is received on another port the current port will go blocking to prevent a loop.
If a forwarding port receives a superior bpdu, the switch will record this bpdu and start transmitting this out its other designated ports.Since this port is forwarding, and this bridge is not the root bridge,this port must be the root port.So the root port has received a supierior bpdu, the stp topology has not changed, and the root port will remain forwarding.