Simple spanning-tree question

[jhaggett]

Say I have 3 switches all connected with redundant links. The switches converge for 30-50 seconds. During this time, will the devices on each switch still talk to the devices on the same switch, or, does EVERY port on the switch go into blocking? Any help would be greatly appreciated.

[dnewell24]

I assume you mean while the network is active and then there is a link failure. Yes they still can communicate locally.

If you are talking during the boot process then no, each port on the switch must transition through the spanning tree states. If you have devices connected to the switch and will not cause a loop, you can enable portfast. I usually configure this on all desktop connected ports. It will allow the port to transition straight to forwarding state.

http://www.cisco.com/en/US/products/hw/routers/ps368/prod_configuration_guide09186a008009163e.html#1028653

It also talks about other methods of speeding up convergence.

[jhaggett]

Thanks so much!