The node denotes the strategy adopted by the PBR.
If strict-priority is configured, the most preferential IP address
is use as redirected nexthop.
If the mode is load-balance, any of the three IP addresses will be
the nexthop and the traffic distributes in the three direction.
Default value is strict-priority.
When L3plus function is not supported, the default value would be set.
It is optional.