Symptom

ASR9K may occasionally select the wrong path towards an N2 prefix. The issue is local on the ASR9k and, depending by the topology, it may generate routing loops for traffic of the specific N2 prefix.

Conditions

This is often triggered by an OSPF recalculation, after which an higher cost path may be wrongly selected in the routing tables. This is a timing issue, which may occasionally show up.

Workaround

An OSPF recalculation may restore the right route, but issue can show up again after a new OSPF recalculation.

Further Problem Description