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New Member

Extending VLANS accross Routed MAN

We have 20+ VLANs on our main network, we have an offsite connected by metro GIG fiber ethernet.  Right now, we have a layer 2 connection to there with the core at the main site as the gateway.  We have had problems occationaly with the metro ethernet's spanning tree which then we would see our own network and cause an outage, not only for the offsite, but since the VLAN would see itself (not on our equipment but the metro ethernet carrier's) it would effect the main network as well. 

What I was going to do to resolve this was change the connection to a routed network, however I need to still send some VLANs over the routed network (there are some applications that require to be on the same subnet as the server).  Is there a way to Map the Vlan 10, and 11 at the main site to a vlan 10, and 11 at the remote site using a routed network?

I noticed there is something about bridging, would I bridge the VLAN accross the routed MAN connection?  Then would I bridge back the other way as well? 

Main site has a 6506E

and offsite has a 3750E


Everyone's tags (3)

Re: Extending VLANS accross Routed MAN


There is at least on solution : L2TP, but I think that 6500 and 3750 will not help you with that.


New Member

Re: Extending VLANS accross Routed MAN

Hi Relder,

The metro-Ethernet connection is to extend layer 2 and you shouldn't have this kind of problem.

You may use Q-in-Q vlans to avoid this kind of problems on the metro's Ethernet switch.

Otherwise, you may use EoMPLS ( Ethernet Over MPLS ) solutions.

Best regards,


New Member

Re: Extending VLANS accross Routed MAN


Yes, I should not have this problems, but it does happen sometimes.  But the price is good which is why we stay.  We just want to shield ourselfs some when It does happen. 

It looks like EoMPLS might be the way to go..

Looks like they have a 3750 Metro Switch, might be alittle different then my 3750-E and 6506-E  But the idea seems to be what I wanted.. Layer 2 over layer 3 routing.

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