Dell PowerConnect B-RX Configuration Manual page 270

7
Configuring forwarding parameters
Figure 11
of the routes is a standard static route and has a metric of 1. The other static route is a null route
and has a higher metric than the standard static route. The device always prefers the static route
with the lower metric. In this example, the device always uses the standard static route for traffic to
destination network 192.168.7.0/24, unless that route becomes unavailable, in which case the
device sends traffic to the null route instead.
FIGURE 11
198
shows an example of two static routes configured for the same destination network. One
Standard and null static routes to the same destination network
Two static routes to 192.168.7.0/24:
--Standard static route through
gateway 192.168.6.157, with metric 1
--Null route, with metric 2
Router A
192.168.6.188/24
When standard static route
is good, Router A uses that
route.
Router A
192.168.6.188/24
If standard static route is
unavailable, Router A uses
the null route (in effect dropping
instead of forwarding the packets).
Null
Router B
192.168.6.157/24
192.168.7.7/24
Router B
192.168.6.157/24
192.168.7.7/24
192.168.7.69/24
X
192.168.7.69/24
BigIron RX Series Configuration Guide
53-1001810-01