Atif,Also you might want to verify your ISIS mtu debug what is being sent out. You are going to have to make sure that the ISIS and Tagging mtu are the same accross both devices.Cheers,Lamar
When you say MPLS is this going to be a rfc 2547 vrf into an ISP. Which is more likely going to be the case. Therefore you are only replacing one data link for another even though MPLS resides on both L2 and L3. More directly you should be fine with...