Billion Electric Company BiGuard 30 - Manual (Page 174)

174
Step 3: Go to Configuration > Dual WAN > General Settings. Select the Fail Over
radio button. Under Connectivity Decision, input the number of times BiGuard 30
should probe the WAN before deciding that the ISP is in service or not (3 by default).
Next, input the duration of the probe cycle (30 sec. by default) and choose the way
WAN ports are probed.