LAN state propagation allows propagating a
LAN port's link state to its corresponding WAN port in a bypass pair.
When LAN connectivity to a downstream switch is lost, the LAN port
state is communicated to the upstream WAN device, thereby allowing
traffic to take alternate paths through other Prisma SD-WAN LAN
ports. LAN State Propagation is applicable only in the LAN-to-WAN
direction. In effect, when a LAN port in a bypass pair goes down,
it also brings down the corresponding WAN port of the bypass pair.
However, in a failure with a WAN port, the LAN port will continue
to remain up.