Cisco Catalyst 4500 Series, Software Configuration Manual

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Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 23 Configuring STP and MST
Configuring MST
0 4096 8192 12288 16384 20480 24576 28672
32768 36864 40960 45056 49152 53248 57344 61440
Switch(config)# spanning-tree mst 1 priority 49152
Switch(config)#
Switch(config)# spanning-tree mst 0 root primary
mst 0 bridge priority set to 24576
mst bridge max aging time unchanged at 20
mst bridge hello time unchanged at 2
mst bridge forward delay unchanged at 15
Switch(config)# ^Z
Switch#
Switch# show spanning-tree mst
###### MST00 vlans mapped: 11-4094
Bridge address 00d0.00b8.1400 priority 24576 (24576 sysid 0)
Root this switch for CST and IST
Configured hello time 2, forward delay 15, max age 20, max hops 20
Interface Role Sts Cost Prio.Nbr Status
---------------- ---- --- --------- -------- --------------------------------
Fa4/4 Back BLK 1000 240.196 P2p
Fa4/5 Desg FWD 200000 128.197 P2p
Fa4/48 Desg FWD 200000 128.240 P2p Bound(STP)
###### MST01 vlans mapped: 1-10
Bridge address 00d0.00b8.1400 priority 49153 (49152 sysid 1)
Root this switch for MST01
Interface Role Sts Cost Prio.Nbr Status
---------------- ---- --- --------- -------- --------------------------------
Fa4/4 Back BLK 1000 160.196 P2p
Fa4/5 Desg FWD 200000 128.197 P2p
Fa4/48 Boun FWD 200000 128.240 P2p Bound(STP)
Switch#
Configuring MST Instance Port Parameters
To configure MST instance port parameters, perform this task:
This example shows how to configure MST instance port parameters:
Switch(config)# interface fastethernet 4/4
Switch(config-if)# spanning-tree mst 1 ?
cost Change the interface spanning tree path cost for an instance
port-priority Change the spanning tree port priority for an instance
Switch(config-if)# spanning-tree mst 1 cost 1234567
Command Purpose
Step 1
Switch(config-if)# spanning-tree mst x cost y
Configures the MST instance port cost.
Step 2
Switch(config-if)# spanning-tree mst x port-priority y Configures the MST instance port priority.
Step 3
Switch(config-if)# Ctrl-Z
Exits configuration mode.
Step 4
Switch# show spanning-tree mst x interface y
Verifies the configuration.