Unified ISSU: Inline LSQ interfaces

Unified in-service software upgrade (ISSU) is supported on inline link services intelligent queuing (IQ) (lsq-) interfaces on MX Series routers. Unified ISSU enables an upgrade between two different Junos OS releases with no disruption on the control plane and with minimal disruption of traffic. The inline LSQ logical interface (lsq-slot/pic/0) is a virtual service logical interface that resides on the Packet Forwarding Engine to provide Layer 2 bundling services that do not need a service PIC.