LAN Routing

Layer 3 InterVLAN routing problem

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Occasional Visitor

Layer 3 InterVLAN routing problem

We've had to change MPLS providers, with a resulting routing change that isn't quite working; I'm hoping someone can check my work and tell me if i'm over looking something.

OLD provider: they gave us Ethernet handoff at both HQ and remote site out of their infrastructure equipment, and I configured the IP addressing and routing. 

HQ:, layer 3 switch at (default gateway for all traffic), interface to MPLS as; switch has config "IP ROUTE" for traffic going to Remote site.

Remote site:, HP 2610-24 PWR layer 3 switch.  PCs on and phones on  Layer 3 switch with two VLANs: VLAN40 ( and VLAN41 (  Those addresses are default gateway for local LANs.  Interface to MPLS at  "IP ROUTE" sends all traffic back to HQ.

Worked like a charm.

New provider puts a router at both sites.  HQ is and is now HQs default route; remote is and is the default route for remote site.  Provider handles MPLS routing in "black box, just trust us" fashion.  So, I told them that everything supposed to go to supernet should go to their router at my remote site, and I'll distribute it further with my layer 3 switch (because once the traffic get there, it has the interVLAN routing in place).

Everybody says that should work, however, only the LAN is accessible; is not.  I've temporarily kept the traffic on my old MPLS so the phones work and have opened a ticket with new provider; I suspect there is a route missing somewhere in their black box.  However, if what I've laid out as basic infrastructure makes sense to anyone, can you tell me if I'm missing anything? 


Occasional Visitor

Re: Layer 3 InterVLAN routing problem

Figured it out.  The problem wasn't on my router, but on the provider's router.  They had to put in a route like so:


so that traffic bound for VLAN41, once it reached their router, knew it had one more hop before it got there.