When the following is configured:
The IRB interface state should be determined based on the state of the associated layer 2 interface.
It can be found in situations of EVPN MPLS multihoming, that the IRB on the PE remains up with this configuration, even when the interface connecting the CE (layer 2 interface) is down.
This does not always occur, and may happen upon DF failover.
This is a software defect, addressed in problem report number 1790705.