Previously there was a bug that effected the 6500s. In this bug if you had a route that covered 0::/96, it would cause the TestFibDevices fail. This bug is back in the 15.2 code for the 7600. Specifically: 15.2(4)S3a I am guessing this is a result of the re-merge of the 7600/6500 code trains. Mack McBride Network Architect