I have an issue getting multicast run across an MPLS Backbone, in a test lab. When all PE's are in the same AS all works fine, 4 PE's in a ring topology. If I reconfigure each PE into a seperate AS, .i.e. AS1, AS2, AS3, AS4. Multicast stops working and the mdt tunnesl are not built.

Using the same as, the mdt tunnels are built and all works ok.

Is there extera configuration to be done wo have the mdt tunnels established across different AS's

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