[c-nsp] ME3600 autoroute & 10G EFP issues

[Eric Van Tol]

> Just curious; why are you running MPLS and your core-facing
> features on an SVI?

The primary reason for this is because these switches are in a ring.  The core facing interface on this switch needs to support VLAN trunking so the ring APS control channel and ring data VLAN can be transported in the core from one router to another.  In other words, the two head-end switches of the ring are not physically connected and are stitched together via MPLS in the core:

     R - R - R
    /         \
   S - S - S - S

> Also, you're lowering your protocol MTU's quite a fair bit,
> even though the physical interface can handle them. Any
> reason why?

Just the way it's always been and I really haven't found a compelling reason to increase them.

> Have you tried running all this on the 10Gbps uplink ports
> natively, and checked again to see whether you see these
> issues?

Yes - changing the port to either a normal switchport with an allowed VLAN list or a routed port works fine.

> I can't recall for which platform, but I think there are
> some restrictions with running MPLS and/or MPLS-TE on an
> SVI.

I was told by the TAC engineer that assisted me with my latest problem that this was a possibility, as MPLS on SVI was only "recently" introduced in 15.3(1).  Frustrating, since not a single TAC engineer I worked with on my case mentioned anything at all about any restrictions.  That said, I now see this:

http://www.cisco.com/en/US/partner/docs/switches/metro/me3600x_3800x/software/release/15.3_3_S/configuration/guide/swmpls.html#wp1289925

"4. MPLS-TE is not supported on SVI."

I guess it's time to look at how the ring is configured and re-evaluate whether a layer 2 ring architecture is worth the weird troubles and randomly supported/unsupported features.

-evt