DCI: The Need for Stretched Layer 2
In the previous article in this DCI series (Why is there a “Wrong Way” to Interconnect Datacenters?) I explained the business case for having multiple data centers and then closed by warning that extending Layer 2 domains was a path to disaster and undermined the resiliency of having two data centers.
Why then is stretching Layer 2 a) needed and b) a go-to maneuver for DCI.
Let's look at it from two points of view: technology and business.