multisegment pseudowire configuration on XE

[sachin30720041]

Hello,

I am configuring multisegment pseudowire on XE routers.

CSR7(gi1)--(gi1)CSR6(gi2)--(gi2)CSR1(gi1)--(gi1)CSR2(gi2)--(gi2)CSR3(gi1)--(gi1)CSR66(gi2)--(gi2)CSR77

CSR7 and CSR6 are part of segment1.

CSR1, CSR2, and CSR3 are part of segment2.

CSR66 and CSR77 are part of segment3.

l2vpn vfi connection is up between CSR1 and CSR3.

CSR1#show l2vpn vfi detail
Pseudo-port interface: pseudowire100001
Interface                          Peer Address      VC ID      S
pseudowire100002             3.3.3.3             12         Y

CSR7 can ping CSR77.

Router#ping 77.77.77.77 source 7.7.7.7
Sending 5, 100-byte ICMP Echos to 100.10.10.66, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 3/5/12 ms

But xconnect between CSR7 and CSR77 is down.

CSR7#show xconnect all

XC     ST                Segment 1 S1                            Segment 2 S2
------+---------------------------------+--+---------------------------------+--
DN     pri                ac Gi2:8(Ethernet)                     DN mpls  77.77.77.77:12 DN

Below is the configuration.

CSR6
----------------
int gi2
ip address 100.10.10.6 255.255.255.0
ip ospf 1 area 0
no sh

int gi1
ip address 100.60.70.6 255.255.255.0
mpls ip
ip ospf 1 area 0
exit

l2 vfi mpw point-to-point
neighbor 7.7.7.7 3232 encap mpls
neighbor 100.10.10.66 3232 encap mpls
exit

router ospf 1
exit

CSR7
---------------

int gi1
ip address 100.60.70.7 255.255.255.0
mpls ip
ip ospf 1 area 0
no sh

router ospf 1
exit

int gi2
no sh
xconnect 77.77.77.77 12 encap mpls
exit

csr1
--------
int gi2
no sh
service instance 100 ethernet
encap untagged
exit

int gi1
ip address 100.10.20.1 255.255.255.0
ip ospf 1 area 0
no sh

int lo0
ip address 1.1.1.1 255.255.255.255
ip ospf 1 area 0
exit

router ospf 1
mpls ldp autoconfig
exit

l2vpn vfi context ctx1
vpn id 123
member 3.3.3.3 12 encap mpls
exit

bridge-domain 100
member gig2 service-instance 100
exit
member vfi ctx1
exit

CSR2
--------------
int gi1
no sh
exit

router ospf 1
mpls ldp autoconfig
exit

int gi1
ip address 100.10.20.2 255.255.255.0
ip ospf 1 area 0
no sh

int gi2
ip address 100.20.30.2 255.255.255.0
ip ospf 1 area 0
no sh

int lo0
ip address 2.2.2.2 255.255.255.255
ip ospf 1 area 0

CSR3
--------------
int gi2
ip address 100.20.30.3 255.255.255.0
ip ospf 1 area 0
no sh

int lo0
ip address 3.3.3.3 255.255.255.255
ip ospf 1 area 0
exit

router ospf 1
mpls ldp autoconfig
exit

int gi1
no sh
service instance 100 ethernet
encap untagged
exit

l2vpn vfi context ctx1
vpn id 123
member 1.1.1.1 12 encap mpls
exit

bridge-domain 100
member gig1 service-instance 100
member vfi ctx1
exit

CSR66
----------------
int gi2
ip address 100.10.10.66 255.255.255.0
ip ospf 1 area 0

mpls ip
no sh

int gi2
ip address 100.66.77.6 255.255.255.0
ip ospf 1 area 0
mpls ip
exit

router ospf 1
exit

l2 vfi mpw point-to-point
neighbor 77.77.77.77 3232 encap mpls
neighbor 100.10.10.6 3232 encap mpls
exit

CSR77
---------------
int gi2
ip address 100.66.77.7 255.255.255.0
ip ospf 1 area 0
mpls ip
no sh

router ospf 1
exit

int gi1
no sh
xconnect 7.7.7.7 12 encap mpls
exit

Thanks,

Sachin

[Harold Ritter · Accepted solution]

Hi @sachin30720041 ,

A targeted LDP session needs to be built between CSR7 and CSR77 using their loopback interface IP address.

Make sure that both CSR7 and CSR77 use their loopback interface IP address as their LDP ID.

CSR7 & CSR77:

mpls ldp router-id Loopback0 force

Regards,

[sachin30720041]

Hello Harold,

That worked!!

I have another question.

if I remove the following lines from the configuration of CSR6 and CSR66 even then xconnect session stays up between CSR7 and CSR77. Then what is the need of having "l2 vfi mpw point-to-point" on CSR6 and CSR66 ?

CSR6:

l2 vfi mpw point-to-point
neighbor 7.7.7.7 3232 encap mpls
neighbor 100.10.10.66 3232 encap mpls
exit

CSR66:

l2 vfi mpw point-to-point
neighbor 77.77.77.77 3232 encap mpls
neighbor 100.10.10.6 3232 encap mpls
exit

But following document mention "l2 vfi <> point-to-point" configuration .

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/mp_l2_vpns/configuration/xe-16/mp-l2-vpns-xe-16-book/l2vpn-multisegment-pseudowires.html