Billion BiPAC 4500NZ(L) User Manual page 69

Note:
1) The time set is for each probe cycle, but the decision to change to the backup port is determined by
Probe Cycle multiplied by connection Decision amount (e.g. From the image above it will be 30
seconds multiplied by 3 consecutive fails, the router will determine failover to WAN2 (backup port)).
2).The failback setting follow the same decision policy as the failover. For example, according to
settings above in the screenshot, the connection probe will be carried out every 30 seconds, and 3
consecutive times of probe success is found, the router will determine failback to WAN1 (main WAN).
Probe WAN 1: Choose the probe policy, to probe gateway or host (users decide themselves)
 Gateway: It will send ping packets to gateway of Wan1 interface and wait for response from it
in every "Probe Cycle" to check the connectivity of the gateway of WAN1 interface.
 Host: It will send ping packets to specific host and wait for response in every "Probe Cycle".
The host must be an IP address.
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