Zhone zNID-GPON-2402 Configuration Manual page 105

Table 37: Ethernet settings
UI Label
LAN Follows WAN
Description
When enabled, the LAN port is forced to a physical down
state when the WAN uplink has been down for 15 seconds.
This mechanism is used to signal to attached devices that
they need to initiate a backup connection. When the WAN
uplink has been back up for 30 seconds, the LAN port is
re-enabled to restore service.
zNID 24xx Series Configuration Guide
Configuration pages
105