Cisco Asr 9000 Series Aggregation Services Router Vpn And Ethernet Services Command Reference, Release - Cisco ASR 9000 Series Reference Manual

Multiple Spanning Tree Protocol Commands
Examples
The following example shows the output from the show spanning-tree mst command, which produces more
detailed information regarding interface state than the standard command as described above:
RP/0/RSP0/CPU0:router# show spanning-tree mst a interface GigabitEthernet0/1/2/1 instance
3
GigabitEthernet0/1/2/1
Cost: 20000
link-type: point-to-point
hello-time 1
Portfast: no
BPDU Guard: no
Guard root: no
Guard topology change: no
BPDUs sent 492, received 3
MST 3:
Edge port:
Boundary : internal
Designated forwarding
Vlans mapped to MST 3: 1-2,4-2999,4000-4094
Port info port id 128.193 cost 200000
Designated root address 0050.3e66.d000 priority 8193 cost 20004
Designated bridge address 0002.172c.f400 priority 49152 port id 128.193
Timers: message expires in 0 sec, forward delay 0, forward transitions 1
Transitions to reach this state: 12
The output includes interface information about the interface which applies to all MSTIs:
• Cost
• link-type
• hello-time
• portfast (including whether BPDU guard is enabled)
• guard root
• guard topology change
• BPDUs sent, received.
It also includes information specific to each MSTI:
• Port ID, priority, cost
• BPDU information from root (bridge ID, cost, and priority)
• BPDU information being sent on this port (Bridge ID, cost, priority)
• State transitions to reach this state.
• Topology changes to reach this state.
Flush containment status for this MSTI.
Related Commands
Command
debug spanning-tree mst packet, on page 479
debug spanning-tree mst protocol-state, on
page 481

Cisco ASR 9000 Series Aggregation Services Router VPN and Ethernet Services Command Reference, Release

show spanning-tree mst interface
Description
Enables debugging for sent and received MSTP packets.
Enables debugging protocol-state changes such as port role
or state changes, topology change notification.
6.1.x
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