PLANET XGS3-24042 - Manual (Page 228)

28-65
Send ARP detection once 3 seconds to detect whether gateway A is reachable, after 3 times detection is
failing, gateway A is considered to be unreachable.
28.4 Kepalive Gteway Troubleshooting
If there is any problem happens when using keepalive gateway function, please check whether the problem is
caused by the following reasons:
 Make sure the device is layer 3 switch, layer 2 switch does not support keepalive gateway
 The detection method is used to point-to-point topology mode only
 Detect IPv4 accessibility by the method, so the detection result only affects IPv4 traffic, other traffic
such as IPv6 is not affected
 Physical state of interface only controlled by physical signal
 Interface can’t run IPv4 after determine gateway is not reachable, so all relative IPv4 routes are deleted
and IPv4 route protocol can’t establish the neighbor on the interface