SonicWALL Internet Security Appliances - Manual (Page 64)

Configuring the TELE3 SP Modem Connection Page 65
Primary Interface
The SonicWALL TELE3 SP automatically detects if a WAN Ethernet connection exists when the
SonicWALL is powered on. Because it can automatically detect the Ethernet connection, the Primary
Interface is Ethernet.
Failover Settings
You can enable WAN failover for the SonicWALL by configuring settings in this section. Select Enable
WAN Failover to use this feature on the SonicWALL. The Secondary Interface Setting defaults to
Modem.
Preempt Mode
Select Preempt Mode if you want the TELE3 SP to re-establish the connection to the WAN Ethernet
interface after a connection failure on the WAN Ethernet port.
Probing on the TELE3 SP
Probing for WAN connectivity occurs over the Ethernet connection, the dial-up connection, or both.
When probing is disabled on the Ethernet link, the SP only performs link detection. If the Ethernet
connection is lost for a duration of 5-9 seconds, the SP considers the Ethernet connection to be
unavailable. If the Ethernet link is lost for 0-4 seconds, the SP does not consider the connection to
be lost. If you are swapping cables quickly, unnecessary WAN failover does not occur on the SP. If
probing is enabled and the cable is unplugged, the 5-9 seconds link detection does not occur.
Instead, the probing rules apply to the connection using the parameters configured for Probe
Interval Time and number of Missed Probes. If probing is enabled on Dial-up, the dial-up connection
is terminated and re-established when probing fails over the modem.
Use the following instructions to configure the Failover Settings:
1. Select Enable WAN Failover.
2. Select Enable Probing.
3. Select an option from the Probe Through menu. Select Ethernet Only to probe the Ethernet WAN
connection and failover to the modem when the connection is lost. Select Modem Only to probe
a dial-up connection and have the modem redial when the dial-up connection is lost. Select
Modem and Ethernet to enable both types of probing on the SP.
4. Enter the IP address for the probe target in the Probe Target (IP Address) field. The Probe IP
address is a static IP address on the WAN. If this field is left blank, or 0.0.0.0 is entered as the
address, the Probe Target is the WAN Gateway IP address.
Tip The probe is a ping sent to the IP address and is used, along with the response, as a method of
determining Internet connectivity.
5. In the Probe Interval (seconds) field, enter the amount of time between probes to the Probe
Target. Five (5) seconds is the default value. To deactivate the Probe Detection feature, enter
zero (0) as the value. In this case, the WAN Failover only occurs when loss of the physical WAN
Ethernet connection occurs on the TELE3 SP.