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Layer 3 InterVLAN routing problem

 
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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: 192.168.20.0/24, layer 3 switch at 192.168.20.251 (default gateway for all traffic), interface to MPLS as 192.168.103.20; switch has config "IP ROUTE 192.168.40.0 255.255.254.0 192.168.103.40" for traffic going to Remote site.

Remote site: 192.168.40.0/23, HP 2610-24 PWR layer 3 switch.  PCs on 192.168.40.0/24 and phones on 192.168.41.0/24.  Layer 3 switch with two VLANs: VLAN40 (192.168.40.251) and VLAN41 (192.168.41.251).  Those addresses are default gateway for local LANs.  Interface to MPLS at 192.168.103.40.  "IP ROUTE 192.168.20.0 255.255.255.0 192.168.103.20" sends all traffic back to HQ.

Worked like a charm.

New provider puts a router at both sites.  HQ is 192.168.20.254 and is now HQs default route; remote is 192.168.40.254 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 192.168.40.0/23 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 192.168.40.0/24 LAN is accessible; 192.168.41.0/24 is not.  I've temporarily kept the 192.168.41.0/24 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? 

 

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Solution

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:

IP ROUTE 192.168.41.0 255.255.255.0 192.168.40.251

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