Showing results for 
Search instead for 
Did you mean: 

Configuring Service instance on ASR900 with redundancy

hello every one ,

Please check attached document ....Our requirement is

Requirement :   Drop tagged data (200,300,400) coming from ASR9000 to respective ASR920 (a,b,c) respectively by using EoMPLS L2VPN  .

Configuration Steps:

1)  Service instance  are created on ASR 907 ,as Router ASR 907 will see vlan tag attached and will send to   respective instance configured on ASR 920 , Service instance are created on destination ASR920 respectively .

2) Uplink on ASR 9000 toward ASR907 is configured as sub interface with Vlan 200,300,400 .

3) Loopback are configured on each ASR .

4) IGP (OSPF with MPLS LDP is configured between internal Ring from 920a to 920c).

4) Configuration on ASR 907 a and ASR 907 b for Service instance are

ASR907a> enable

ASR907a# configure terminal

ASR907a (config)#interface TenGigabitEthernet 0/0/0

ASR907a(config)#description **Connected to ASR9K**

ASR907a (config-if)#no ip address

ASR907a (config-if)#no shut


ASR907a (config-if)# service instance 200 ethernet

ASR907a (config-if-srv)# encapsulation dot1q 200

ASR907a (config-if-srv)# xconnect 200 encapsulation mpls

ASR907a (config)# exit


ASR907a (config-if)# service instance 300 ethernet

ASR907a (config-if-srv)# encapsulation dot1q 300

ASR907a (config-if-srv)# xconnect 300 encapsulation mpls

ASR907a (config)# exit


ASR907a (config)# service instance 400 ethernet

ASR907a (config-if-srv)# encapsulation dot1q 400

ASR907a (config-if-srv)# xconnect 400 encapsulation mpls

ASR907a (config)# exit 


same on ASR 907b


 Configuration Steps on ASR 920 a,   are


ASR920a (config)#interface gigabitethernet 0/0/2

ASR920a (config)#description **Connected to CE Node**

ASR920a (config-if)#no ip address

ASR920a (config-if)#no shut

ASR920a (config-if)# service instance 200 ethernet

ASR920a (config-if-srv)# encapsulation dot1q 200

ASR920a (config-if-srv)# xconnect 200 encapsulation mpls

ASR920a (config)# backup peer 200 pw-class pw1

ASR920a (config)# backup delay 5

ASR920a (config)# exit


Configuration Steps on ASR 920 b for EoMPLS L2 VPN


ASR920b(config)# pseudowire-class pw1

ASR920b(config-pw-class)# encapsulation mpls

ASR920b(config)# backup delay 0 10


ASR920b (config)#interface gigabitethernet 0/0/1

ASR920b (config)#description **Connected to CE Node**

ASR920b (config-if)#no ip address

ASR920b (config-if)#no shut

ASR920b (config-if)# service instance 300 ethernet

ASR920b (config-if-srv)# encapsulation dot1q 300

ASR920b (config-if-srv)# xconnect 300 encapsulation mpls

ASR920b (config)# backup peer 300 pw-class pw1

ASR920b (config)# backup delay 5

ASR920b (config)# exit


Configuration Steps on ASR 920 c for EoMPLS L2 VPN


ASR920c(config)# pseudowire-class pw1

ASR920c(config-pw-class)# encapsulation mpls

ASR920c(config)# backup delay 0 10


ASR920c (config)#interface gigabitethernet 0/0/0

ASR920c (config)#description **Connected to CE Node**

ASR920c (config-if)#no ip address

ASR920c (config-if)#no shut

ASR920c (config-if)# service instance 400 ethernet

ASR920c (config-if-srv)# encapsulation dot1q 400

ASR920c (config-if-srv)# xconnect 400 encapsulation mpls

ASR920c (config)# backup peer 400 pw-class pw1

ASR920c (config)# backup delay 5

ASR920c (config)# exit


Confusion point : Do I need to add "rewrite ingress tag pop 1 symmetric"


Please check and reply ......your prompt guide will be appreciated.

Best Regards


Elvin Arias Soto
Cisco Employee

Rewrite is only needed when you want to manipulate the tags on the EFP.




Hi, it's depend of the scenario. So follow your description I recommend to use the commands "rewrite ingress tag pop 1 symmetric" .



Cisco Employee

Hi Nuhu,


"rewrite ingress tag pop 1 symmetric" is not required for your use case. Because you are matching and dropping packets with tag 200, 300 or 400.


"rewrite ingress tag pop 1 symmetric" will be useful if you need to handle different services across the MPLS cloud.



Content for Community-Ad

This widget could not be displayed.