Used for setting whether to forward or discard NS packets received from the network side when the user is offline.
It takes effect only when the NS unicast function is enabled.
Options:
1. forward(1) -indicates that NS packets are broadcast to ports inside the VLAN on the user, cascading, and network sides.
2. discard(2) -indicates that NS packets are discarded on the user side, and only broadcast to ports inside the VLAN on the cascading and network sides.
Default: forward(1)