Dell N2000, N3000, N4000 MSTP Configuration Example

Configuring the Spanning Tree Protocol 753
The administrator also configures Port Fast BPDU filtering and Loop Guard
to extend STP’s capability to prevent network loops. For all other STP
settings, the administrator uses the default STP values.
To configure the switch:
1
Connect to Switch A and configure the priority to be higher (a lower
value) than the other switches, which use the default value of
32768 .
console#config
console(config)#spanning-tree priority 8192
2
Configure ports 4–20 to be in Port Fast mode.
console(config)#interface range gi1/0/4-20
console(config-if)#spanning-tree portfast
console(config-if)#exit
3
Enable Loop Guard on ports 1–3 to help prevent network loops that might
be caused if a port quits receiving BPDUs.
console(config)#interface range gi1/0/1-3
console(config-if)#spanning-tree guard loop
console(config-if)#exit
4
Enable Port Fast BPDU Filter. This feature is configured globally, but it
affects only Port Fast-enabled access ports.
console(config)#spanning-tree portfast bpdufilter
default
5
Repeat step 2 through step 4 on Switch B, Switch C, and Switch D to
complete the configuration.
MSTP Configuration Example
This example shows how to configure IEEE 802.1s Multiple Spanning Tree
(MST) protocol on the switches shown in Figure22-20.