Black Box 12 VDC load User Manual page 8

Note: The A/B Switch monitors the WAN
connections by PINGing the far side router
thru the primary WAN link. If the primary WAN
link fails, the A/B Switch auto switches to the
backup WAN link. When the primary WAN
link is available again, the A/B Switch auto
switches back to the primary.
router
1.1.10.1
Network 1
The monitorip address and monitormac address parameters can be configured to allow the A/B Switch to monitor
connectivity to any device within, or outside of the A/B Switch's subnet. If monitoring connectivity to a device on
the same subnet as the A/B Switch's internal Ethernet node, set the A/B Switch's monitorip address and monitormac
address parameters to the IP address and MAC address of the device being monitored. If monitoring connectivity to
a device on a different subnet/network than the A/B Switch's internal Ethernet node, set the A/B Switch's
monitormac address parameter to the MAC address of the gateway router on the A/B Switch's subnet, and set the
monitorip address parameter to the IP address of the device being monitored. This allows the PING packet issued by
the A/B Switch to be routed through the gateway router to the target device on a different subnet/network. If you
don't know the MAC address of the target device or the gateway router on the A/B Switch's subnet, one method is
to open a command prompt window on a P.C. attached to that same subnet and use the "arp -a" command to retrieve
this information from the P.C.'s arp cache (you may need to PING the IP address first before the entry will appear in
the arp cache).
In most network environments rather than manually configuring the monitormac address, you can configure the A/B
Switch to automatically determine the proper MAC address required for the PING packet. Enter the monitorip
address information as noted above, and then set the monitormac address parameter to 00 00 00 00 00 00. This
causes the A/B Switch to issuing an ARP request to the gateway router which will respond with the appropriate
MAC address information needed.
NOTE: When the Auto Switch feature is enabled, manual switching can be performed, but will be overridden
by any auto switching commands that are subsequently issued by the A/B Switch.
A/B SWITCH WITH REMOTE INTERFACE
Auto Failover & Auto Recovery
A/B Switch
A
C
B
Network
Port
PING 2.2.20.1
E/N
switch
backup
backup
WAN
WAN
primary primary
WAN WAN
router
2.2.20.1
Network 2
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