Chapter 8 WAN Screens
8.6 TCP/IP Priority (Metric)
The metric represents the "cost of transmission". A router determines the best route for
transmission by choosing a path with the lowest "cost". RIP routing uses hop count as the
measurement of cost, with a minimum of "1" for directly connected networks. The number
must be between "1" and "15"; a number greater than "15" means the link is down. The
smaller the number, the lower the "cost".
1 The metric sets the priority for the ZyWALL's routes to the Internet. Each route must
have a unique metric.
2 The priorities of the WAN interface routes must always be higher than the dial-backup
and traffic redirect route priorities.
Lets say that you have the WAN operation mode set to active/passive, meaning the ZyWALL
uses the second highest priority WAN interface as a back up. The WAN 1 route has a metric of
"2", the WAN 2 route has a metric of "3", the traffic-redirect route has a metric of "14" and the
dial-backup route has a metric of "15". In this case, the WAN 1 route acts as the primary
default route. If the WAN 1 route fails to connect to the Internet, the ZyWALL tries the WAN
2 route next. If the WAN 2 route fails, the ZyWALL tries the traffic-redirect route. In the same
manner, the ZyWALL uses the dial-backup route if the traffic-redirect route also fails.
The dial-backup or traffic redirect routes cannot take priority over the WAN 1 and WAN 2
routes.
8.7 WAN General
Click NETWORK > WAN to open the General screen. Use this screen to configure load
balancing, route priority, and connection test properties.
WAN 2 refers to either the physical WAN 2 port on a ZyWALL with multiple
WAN ports or the 3G card on a single WAN ZyWALL in router mode.
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ZyWALL 5/35/70 Series User's Guide