[c-nsp] Nexus 7k and OTV

[Lincoln Dale]

On 22/07/2010, at 8:16 PM, Matthew Melbourne wrote:

> Is it possible to extend two vDCs between Data Centres using OTV (pair
> of N7k on each site) - it's not clear how OTV uses vDCs to extend the
> L2 domain.

yes, its possible.  there are 3 methods:

1. OTV runs inside a Virtual Device Context.  for 2 VDCs you could run OTV in each of them.
   this approach requires 'WAN' connectivity to each VDC - perhaps a downside if its not already there.

2. if you don't have overlapping VLANs between the VDCs then you can trunk the VLANs (L2) from one VDC to another using a crossover external cable (1G or 10G or Nx1G/10G depending on your traffic levels), then use a single OTV instance to transport all the VLANs between sites.

3. you could run a single instance of OTV within each VDC (similar to #1) with the 'WAN' IP connectivity to the OTV cloud achieved via a single VDC with a crossover external cable (1G or 10G, doesn't really matter) @ L3 between VDCs to the single VDC that has WAN connectivity (similar to #2).  i.e. sort of a hybrid of the above two.

> Also, is it correct that Unicast-only transport support (and hence the
> use of an Adjacency Server) is not supported initially (looking at the
> BRKDCT-2049 Networkers' presentation).

correct.


> 
> Alternatively, are there other mechanisms to achieve L2 connectivity
> for two separte L2 domains over a pair of redundant links between Data
> Centres?

quite a few ways of doing it, but OTV does solve some unique problems and issues with the various other approaches.


cheers,

lincoln.