Dell PowerConnect B-FCXs Configuration Manual page 868

26
Configuring IP parameters – Layer 3 Switches
Figure 129
this example, one 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 Layer 3 Switch
always prefers the static route with the lower metric. In this example, the Layer 3 Switch 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 Layer 3 Switch sends traffic to the null route instead.
FIGURE 129
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
Figure 130
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 Layer
3 Switch always prefers the interface-based route when the route is available. However, if the
interface-based route becomes unavailable, the Layer 3 Switch still forwards the traffic toward the
destination using an alternate route through gateway 192.168.8.11/24.
826
shows an example of two static routes configured for the same destination network. In
Standard and null static routes to the same destination network
192.168.6.188/24
Switch A
When standard static route
is good, Switch A uses that
route.
192.168.6.188/24
Switch A
If standard static route is
unavailable, Switch A uses
the null route (in effect dropping
instead of forwarding the packets).
Null
shows another example of two static routes. In this example, a standard static route
192.168.6.157/24
Switch B
192.168.6.157/24
Switch B
PowerConnect B-Series FCX Configuration Guide
192.168.7.7/24
192.168.7.69/24
192.168.7.7/24
X
192.168.7.69/24
53-1002266-01