EoMPLS

[msuga]

Hi, I'm trying to use EoMPLS to connect two VLANS located on different Gigabit Ethernet Rings. The EoMPLS tunnel was created between Cisco 6500 and Cisco 10700.

Using the same VLAN ID on both sides of EoMPLS tunnel I don`t have any problem but when I try to use different VLAN IDs, EoMPLs tunnel stays UP but I can`t pass any traffic.

Anybody knows if I need to use the same Vlan ID on both sides of EoMPLS tunnel ?

Which are the differences between vc-type Ethernet and vc-type VLAN?

[vkapoor5]

I think you can use different vlan ids on both sides, but the VC identifier has to be same on both sides. As far as vc-type is concerned, one is vlan based forwarding and other is port based forwarding. This doc talks about that :

http://www.cisco.com/univercd/cc/td/doc/product/lan/cat6000/12_1e/comref/m1.htm#74352

[msuga]

Thanks for your response. I don't understand what is the difference between vc-type vlan and vc-type ethernet. Once the command is applied on Interface vlan, I can`t understand the difference between "port" based forwarding and "vlan" based forwarding.

[danhut]

In vlan based VCs we encapsulate all traffic received on the subinterface into the EoMPLS VC - this includes the dot1q vlan tag and and 802.1p bits.

In port mode (VC type ethernet) we strip the outer vlan tag (if there is one - like in the case of dot1q tunnels) and transport the rest over EoMPLS.

If you use different vlans at each end of the VC, IOS should be able to do a vlan re-write in the case of a vlan based VC. You could probably force the VC to be port mode (ethernet type) by adding the VC-type command after the "mpls l2-transport" command to see if that helps. (Could be an IOS inter-op issue if this does not work on its own)