device# configure terminal
device(config)# protocol spanning-tree mstp
device(config-mstp)# region connemara
device(config-mstp)# revision 1
device(config-mstp)# instance 1 vlan 2,3
device(config-mstp)# instance 2 vlan 4-6
device(conf-Mstp)# instance 1 priority 28672
device(conf-Mstp)# max-hops 25
device(conf-Mstp)# end
device# show spanning-tree mst Spanning-tree Mode: Multiple Spanning Tree Protocol CIST Root Id: 8000.609c.9f5d.4800 (self) CIST Bridge Id: 8000.609c.9f5d.4800 CIST Reg Root Id: 8000.609c.9f5d.4800 (self) CIST Root Forward Delay: 15; Hello Time: 2; Max Age: 20; Max-hops: 20 Configured Forward Delay: 15; Hello Time: 2; Max Age: 20; Max-hops: 25; Tx-HoldCount: 6 Number of topology change(s): 0 Bpdu-guard errdisable timeout: disabled Bpdu-guard errdisable timeout interval: 300 sec Migrate Time: 3 sec Name : connemara Revision Level : 1 Digest : 0xD5FF4C3F6C18E2F27AF3A8300297ABAA Instance VLAN -------- ---- 0: 1,7,8,9 1: 2,3 2: 4-6
Note
Observe that the settings comply with the formula set out in the STP parameters section, as:
(2 × (forward delay - 1)) ≥ maximum age ≥ (2 × (hello time + 1))
or in this case: 28 ≥ 20 ≥ 6.
device# show running-config | begin spanning-tree protocol spanning-tree mstp instance 1 vlan 2,3 instance 1 priority 28672 instance 2 vlan 4-6 region connemars revision 1 max-hops 25 ! ...
device# copy running-config startup-config
device# configure terminal device(config)# protocol spanning-tree mstp device(config-mstp)# region connemara device(config-mstp)# revision 1 device(config-mstp)# instance 1 vlan 2,3 device(config-mstp)# instance 2 vlan 4-6 device(conf-Mstp)# instance 1 priority 28582 device(conf-Mstp)# max-hops 25 device(conf-Mstp)# end device# show spanning-tree mst device# copy running-config startup-config