Ethernet Virtual Circuit question

[aljoush12]

Hello Experts, 

I am new to EVC. I am trying to configure evc where device B receives an untagged packet and pushes vlan 22 onto the egress and device C receives it and pops the tag and sends it to D. I need to create multiple service instances with encapsulation dot1q on the port channel because encapsulation untagged doesn't support on multiple service instances on a same interface. Routers B and C are ASR920. 

                                                                                   Port-channel 1

A ------> untagged packet --------> B -------> tagged with vlan 22 -----------> C --------> untagged packet -------> D 

I tried this config below on Po1 but it didn't work. Could please let me know if this is doable or if I am doing wrong here? I appreciate your help.  

Router B:

interface Port-channel1

 no ip address

 service instance 22 ethernet

  encapsulation dot1q 22

  rewrite ingress tag push dot1q 22

  bridge-domain 22

[MHM Cisco World]

  rewrite ingress tag push dot1q 22 <<- add this on Router-B and Router-C interface that receive untag traffic not config it under Port-Channel.

Thanks A Lot
MHM

[aljoush12]

Hi MHM, 

Thank you for your reply. I have two members on the port-channel 1. I have the config below on both routers B and C. Are you suggesting to configure it on the member interfaces but not on the Port-channel interface?  

interface Port-channel1

 no ip address

 service instance 22 ethernet

  encapsulation dot1q 22

  rewrite ingress tag push dot1q 22

  bridge-domain 22

[MHM Cisco World]

interface1-B-PO
config this on interface not on PO nor it port member 

[aljoush12]

Hi MHM, 

Here is my config on Router B. Please let me know if this is what you are suggesting. 

A ------> untagged packet --------> gi2 B gi1 -------> tagged with vlan 22 -----------> gi1 C  gi2--------> untagged packet -------> D 

interface GigabitEthernet2

 no ip address

 negotiation auto

 service instance 22 ethernet

  encapsulation untagged

  rewrite ingress tag push dot1q 22

  bridge-domain 22

 !

end




interface BDI22

 ip address 10.102.0.90 255.255.255.248

 vrrp 1 ip 10.102.0.89

 vrrp 1 priority 200

end





interface GigabitEthernet1

 no ip address

 negotiation auto

  channel-group 20 mode active

end




interface Port-channel20

 no ip address

 no negotiation auto

  service instance 22 ethernet

  encapsulation dot1q 22

  bridge-domain 22

 !

end

[MHM Cisco World]

Yes exactly, you push the vlan22 tag in ingress of frame. 
did you check this solution ? 

note:- you must apply same in Router C

[aljoush12]

Hi MHM, 

Please see my config below. I am not able to ping10.102.0.91 in Router C from Router B 10.102.0.90 since it is expecting the tag 22. 

A ------> untagged packet --------> gi2 B gi1 -------> tagged with vlan 22 -----------> gi1 C  gi2--------> untagged packet -------> D 

Router B

interface GigabitEthernet2

 no ip address

 negotiation auto

 service instance 22 ethernet

  encapsulation untagged

  rewrite ingress tag push dot1q 22

  bridge-domain 22




interface BDI22

 ip address 10.102.0.90 255.255.255.248

 vrrp 1 ip 10.102.0.89

 vrrp 1 priority 200





interface GigabitEthernet1

 no ip address

 negotiation auto

  channel-group 20 mode active




interface Port-channel20

 no ip address

 no negotiation auto

  service instance 22 ethernet

  encapsulation dot1q 22

  bridge-domain 22





Router C 





interface GigabitEthernet2

 no ip address

 negotiation auto

 service instance 22 ethernet

  encapsulation untagged

  rewrite ingress tag push dot1q 22

  bridge-domain 22




 interface BDI22

 ip address 10.102.0.91 255.255.255.248

 vrrp 1 ip 10.102.0.89

 vrrp 1 priority 200




interface GigabitEthernet1

 no ip address

 negotiation auto

 channel-group 20 mode active




interface Port-channel20

 no ip address

 no negotiation auto

 service instance 22 ethernet

  encapsulation dot1q 22

  bridge-domain 22

[MHM Cisco World · Accepted solution]

  rewrite ingress tag push dot1q 22 symmetric <<- this need to do reverse when packet out do in both router 

[aljoush12]

Hi MHM, 

That did it. Thank you so much!

[MHM Cisco World]

You are welcome 

Have a nice weekend 

MHM