How much
PortFast is actually fast? Well, let’s see.
For this
purpose I will use debug for spanning-tree to see how much it is take to make
interface in forwarding state.
SW_1#debug spanning-tree events
I choose
interface FastEthernet 1/10 on my SW_1, and I shutdown interface.
That
interface is in VLAN 1 and it is access port, because PortFast have to be configured
on access port only, not trunk port.
So let’s
make this interface UP/UP…
SW_1(config)#interface fastethernet 1/10
SW_1(config-if)#no shutdown
SW_1(config-if)#
*Mar 1
00:33:20.215: STP: VLAN1 Fa1/10 -> listening -- 15 sec forward delay
*Mar 1
00:33:35.231: STP: VLAN1 Fa1/10 -> learning -- 15 sec forward
delay
*Mar 1
00:33:50.255: STP: VLAN1 Fa1/10 -> forwarding
SW_1(config-if)#
