Brocade BigIron RX Series Configuration Guide - Manual (Page 287)

BigIron RX Series Configuration Guide 209
53-1002484-04
Configuring forwarding parameters
7
FIGURE 11 Standard and null static routes to the same destination network
Figure 12 shows another example of two static routes. A standard static route and an
interface-based static route are configured for destination network 192.168.6.0/24. The
interface-based static route has a lower metric than the standard static route. As a result, the
device always prefers the interface-based route when the route is available. However, if the
interface-based route becomes unavailable, the device still forwards the traffic toward the
destination using an alternate route through gateway 192.168.8.11/24.
X
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 Router B
192.168.6.188/24 192.168.6.157/24 192.168.7.7/24
192.168.7.69/24
When standard static route
is good, Router A uses that
route.
Router A Router B
192.168.6.188/24 192.168.6.157/24 192.168.7.7/24
192.168.7.69/24
If standard static route is
unavailable, Router A uses
the null route (in effect dropping
instead of forwarding the packets).
Null