Cisco ASR 903 - Verify Spanning-Tree Configuration

Layer 2 Solution
Spanning-Tree Configuration ▀
Cisco ASR 903 Router Design and Deployment Guide▄
OL-30526-01
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Figure 3. Spanning Tree
ASR903-PE2
Gi0/1/2 Gi0/1/2
Gi0/1/0 Gi0/1/2Gi0/1/0Gi0/1/1
ASR903-PE1ASR903-CE1
Customer A
Site 1
ASR903-CE2
172.16.11.0/24 - SubnetB
172.16.11.0/24 – SubnetB
Customer A
Site 2
10 10 10
40 11
10 10
11 40 11
30
11 11 11
172.16.10.0/24 - SubnetA
172.16.10.0/24 – SubnetA
10 30
Gi0/1/1 Gi0/1/1
x
ASR903-PE1 and ASR903-PE2 Configuration
spanning-tree mode mst ! enable MST on the ASR903
interface GigabitEthernet0/1/1
no ip address
negotiation auto
service instance trunk 1 ethernet
encapsulation dot1q 30-40
rewrite ingress tag pop 1 symmetric
bridge-domain from-encapsulation
!
service instance 2 ethernet
encapsulation untagged ! enable l2protocol peering
l2protocol peer
bridge-domain 1
interface GigabitEthernet0/1/2
no ip address
negotiation auto
service instance trunk 1 ethernet
encapsulation dot1q 30-40
rewrite ingress tag pop 1 symmetric
bridge-domain from-encapsulation
!
service instance 2 ethernet
encapsulation untagged
l2protocol peer ! enable l2protocol peering
bridge-domain 1
Verify Spanning-tree Configuration
ASR903-PE1# show span vlan 30
MST0
Spanning tree enabled protocol mstp
Root ID Priority 32768
Address 7010.5c51.8fbb