Layer 2 Actibe/Active extension between two ACI Fabrics

[abbasali5]

If I have two Data Centers with Cisco ACI Fabric. What will be the best way to connect them in Active/Active mode with WAN bandwidth requirements.   Do I need a separate leaf switches at both datacenters to connect to WAN link between the two data centers.  It will be a Layer 2 extension over MPLS so I have two options:  OTV or VXLAN which I think will require another pair of Nexus switches such as 7000/5000.  Not sure if it makes sense to spend so much money on Nexus 7000/5000 just to support Layer 2 Extension across Active/Active Data Centers.  Our ACI Networks between two datacenters are  not very huge so is there a more cost effective route for Layer 2 extension with Active/Active support.

Thanks,

[adeboye.adeoso]

 - DCI is an solution you deploy to interconnect multiple datacenters and extend Layer 2 and/or Layer 3 with or without multi-tenancy.  A DCI solution relies on a Data Plane for the Transport and a Control plane for an efficient and solid mechanism for endpoint discovery and distribution between sites (and much more).  

That been said, 

Three DCI options are proposed

●  One very simple option, limited to dual-site deployments, uses vPC. In this case, the border leaf switches of both fabrics are simply connected back to back using either dark fiber of DWDM connections.

●  The second option uses the most popular DCI technology: OTV. It is still uses vPC to connect to the fabric, but it uses a Layer 3 routed connection over the core network.

●  The third option is still emerging. It uses VXLAN technology to offer Layer 2 extension services across sites. (Although i hear this is available in 2017 amongst my friends in Cisco)

http://www.cisco.com/c/en/us/solutions/data-center-virtualization/application-centric-infrastructure/white-paper-c11-737077.pdf

HTH

Adeboye