Question 1 – Consider the following question:
The classic STP protocol is known for its slow response time to network failures. In order to improve network convergence, configure the switches so that any device is able to detect and respond to an indirect link failure in 20 seconds.
I see two possible answers – Either enable Backbonefast on all switches and adjust the forward-delay to 10 seconds ( INE Answer) or adjust the STP timers on the Root and all other switches to – Hello – 2, Forward-delay – 7, Max Age – 6 ( My answer) ? ?
It seems to me, that using the timers above on all switches will guarantee a recovery anywhere in the network in 20 seconds? Having said that, I do understand how Backbonefast uses RLQ’s to update switches when an indirect failure occurs and how setting the forward-delay to 10 seconds could ensure a recovery in 20 seconds.
Question 2 – Can anyone please recommend some good documentation on the Doc CD that might assist a CCIE candidate, should he be asked to use Access-maps to filter traffic across the VLAN? As you know, all L2 traffic is dropped in the Access-map if not specifically permitted through the filter. I’m having a lot of trouble recalling Ethertypes for this type of filtering. I have no problem remembering easy ones like ARP (0×806), but PVST and other L2 ethertypes are pretty tough!!! Any suggestions on this?