Open Stack

On Tue, Oct 28, 2014 at 20:01:40, Kevin Benton wrote:
> I think the simplest use case is just that a provider doesn't want to
> deal with extending L2 domains all over their datacenter.

This is the core motivation. As mentioned in Fred Baker's internet draft[0], extending layer 2 domains can be extremely challenging, and we've found it to be problematic to debug at setup time, let alone to operate.

If your tenants have no need of layer 2 networks (i.e. their workload is all-IP), the datacenter network becomes much simpler in a routed model. Generally speaking, simpler is better!

Cory

[0]: https://tools.ietf.org/html/draft-baker-openstack-ipv6-model-00