I got a problem here, the HQ and the branch connected by the mpls which is belongs to bell. Now ,the branch can not reach the serer in the HQ. I check the branch , the router is ok, But can not ping the server . but when I ping the branch from our core switch, it is pingable. but the branch is failed to ping the core. I traceroute from the core and I ping from the branch hop by hop, the PE router is the problem. Is anyone can give me some idea about this?