Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

100Mpbs leased circuit


We have 1x100Mbps leased circuit connecting two locations. The links has been tested by connecting two laptops at both ends by assigning /30 IP addresses; Ping is successful; [As per my understanding no issue with Layer 1 & 3];

We have connected the same links at one end one of our Core switches 5509 and at other end 6513, which are in VTP Domain model. We are using Dot1q trunk between these two switches;

We are still unable to see the VLAN traffic between these two switches over the new 100 Mbps link.

As per the service provider 100 Mbps link is an ethernet extension terminated at SDH;

I guess, the issue might be related with Layer-2 problem. Can anyone pl help us in elaborating the problem and solution as well.

New Member

Re: 100Mpbs leased circuit

You might be experiencing an MTU issue at the provider level.

If the provider is running this circuit over MPLS or MetroEthernet and didn't configured/allocate/provisioned the circuit with the correct MTU you are going to see this behavior.

Try setting the mtu to 1494 or less in your interfaces and see if it works.