L2VPN (xconnect) and link bundling - design question

[benediktsv]

Hello

So we are running 4x ASR 9k chassis in four locations spread around european cities.

At the moment we have 2x 10Ge connections between each site and they are configured in a L3 LACP bundle.

over this bundle we run IPv4 and MPLS, IPv4 is natively used for IP transit and MPLS is used to provide us with L2VPN / xconnect features

So - in the original design we where to use BFD/BoB to ensure the bundles had a FFD 

Now we have another issue with load balancing some big L2VPN's over the two (or more in the future) links between sites.

One plan is to remove the bundle, run IS-IS/BFD and IPv4 on and use CEF to load balance. 

We are unsure how that will affect the L2VPN 

So the question is - what is the "correct" way of doing this - do SP's generally use LACP bundles ? main issues is FFD and load balance the L2VPN's

 We are fine using a bundle for the IP transit if we add BoB for FFD. 

- Benni

[Alexei Kiritchenko]

Hello Benni,

with L2VPN traffic load balancing is done on a MPLS label making all traffic from one PE to another PE  for the same PW to take single path. 
Since 4.2.1 ASR9k supports Flow Aware Transport Pseudo wire (FAT PW) where every flow would get an additional label making load balancing to work for L2VPN traffic.
Regards,
/A