notgoing2failnotgoing2fail Member Posts: 1,138
I learned something about STP tonite I'd like to share.

You can enable BPDU guard in 2 ways.

1) configuration mode
spanning-tree portfast bpduguard

This will enable the protection on all interfaces already setup in portfast mode.

2) However you can't use the same command within the interface mode itself as it's different. This is what irks me!

Anyways, to enable it on the interface itself, the command is:

spanning-tree bpduguard enable

Also another tip. In STP, the hello BPDU's occur every 2 seconds coming from the root down. The switches then forward the BDPU's to other switches. But in RSTP, all switches provide the BPDU's every 2 seconds regardless of what the root switch does....

Back to STP, if the switches don't get the hellos from the root, they don't do anything as far as letting other switches know....

I'm pretty sure that's correct, feel free to point out any areas I'm off on...


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