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Forwarding l2mpls over traffic engineering tunnel is not a bit complex but a tricky one. This all depends over the requirement how the service provider wants to route the traffic of backhauls. In this test setup we have implemented the MPLS TE for a single customer rest of the traffic of backhaul will follow the traditional IGP path. 
The two options available in pseudo wire to forward the l2mpls traffic over te tunnel.
preferred-path peer
preferred-path tunnel interface

In this test result, option a is used to route the only customer traffic. If option b is used with auto-route announce, in that case the full backhaul traffic follow the tunnel path which may create more problems.

How to use preferred-path peer option
To use this option a loopback 100 is created on R3 which is the tunnel tail-end router and is not announced in the IGP. The reason for not announcing in IGP is that because when the tunnel path will get disconnect, the traffic will fall to the normal IGP path. This could be disabled by using fallback option in preferred-path command.
On R1 a TEST pseudowire is created with preferred-path peer and a static route is imposed on R1 for with next hop as tunnel 10.

Configuration of R1
pseudowire-class TEST
 encapsulation mpls
 preferred-path peer 

ip route Tunnel10

interface Tunnel10
 ip unnumbered Loopback0
 tunnel destination
 tunnel mode mpls traffic-eng
 tunnel mpls traffic-eng path-option 1 explicit name R3
 no routing dynamic

ip explicit-path name R3 enable

Commands Need To Be Enabled On All RSVP Participating Interfaces
mpls traffic-eng tunnels
 ip rsvp bandwidth 200 200

Global Config Commands
mpls traffic-eng tunnels

Commands for OSPF
router ospf 1
 mpls traffic-eng router-id Loopback0
 mpls traffic-eng area 0

Test Results
Refer figure 1
Check the status of vc which is bind on Ethernet 2/3 (Customer Facing Interface) 

The label bind for vc 100 is showing 16 and it will become the remote label for the another router where the circuit is going to terminate.

The given output is showing explicitly that 16 is the label which is used for vc 100 and is the local label of R3 router. 19 label is used for IGP which is being used for MPLS traffic engineering tunnel.

The given output is showing the status of tunnel 10 which is used for forwarding. The outlabel is showing 19 with outgoing interface fast ethernet0/1 which is not the best IGP path. All the l2 traffic will forward over this tunnel. 

After forwarding packet from R1 to R2, the top label 19 should be popped off because of PHP. The given output is showing the same.

Check the ping from CE device which is R5 and R6

Shivlu Jain