[c-nsp] acl on bvi in ios xr (9k) 4.1.2

[Peter Rathlev]

On Mon, 2012-07-23 at 10:14 +0200, adam vitkovsky wrote:
> > one router, two different switches, both switches are standalone and have
> > no multi-chassis capabilities.
>
> If there's the same VLAN  running of the two switches you could
> terminate it on two separate L3 sub-interfaces on the ASR9K /breaking
> the VLAN subnet in two -loosing 4 addresses
> Or instead of the BVI you could use a PW to aggregate the L2 traffic
> form the disjoint VLAN and terminate the PW at ASR9K running L3 for
> the aggregation ring
> Or you can use the already mentioned L2 switch to aggregate the VLANS
> from the two switches and connect it via trunk to ASR9K

This is the scenario:

         +----------+
         |  Router  |
         +----------+
           |      |
 +----------+    +----------+
 | Switch 1 |    | Switch 2 |
 +----------+    +----------+

Suggestion 1, using two different subinterfaces and 2 networks, would
exclude connecting to the same VLAN (not just ID) on the other side.
Imagine the two switches running e.g. HSRP on a SVI.

Suggestion 2 does not fall into the category "simple solution". And I
fail to see how it introduces redundancy for the ASR9k, but that's
probably because I'm not familiar with that way of doing it.

Suggestion 3 does not introduce redundancy for the ASR9k.

Summa summarum: There's no simple way to do it other than BVI. One might
say that this kind of redundancy is irrelevant for a router of that
size, but that's beside the point here.

-- 
Peter