[c-nsp] 3750/4500 as PE?

[Peter Rathlev]

On Wed, 2009-05-06 at 14:42 -0400, Jeff Kell wrote:
> Anyone running a 3750 or 4500 as a PE router (nothing fancy, just
> inter-VRF iBGP that really "imports/exports" routes)?
> 
> We have a VRF-lite network but at this point only one iBGP mesh point
> (PE).  There are cases where some of the nodes attached to the current
> PE could ideally route between VRFs locally without spitting it out to
> the PE and back.  In our case we have a "core services" VRF that is
> essentially imported into every VRF.  It's a straight shot across the
> core IX subnet if I could put the "core services" presence on some of
> the CEs rather than the extra hop to route through the core.

If you're just looking for route leaking the 3750 can do that with just
the MP-BGP you might already have defined in a VRF Lite network.

Look out for TCAM starvation; the 3750 can hold ~8k routes (with the
"routing" SDM template) so it might not be the best PE. Leaking between
VRFs means a single prefix takes up multiple TCAM entries.

Regards,
Peter