34-30
Cisco Catalyst Blade Switch 3020 for HP Software Configuration Guide
OL-8915-03
Chapter 34 Configuring IP Unicast Routing
Configuring Protocol-Independent Features
Configuring Static Unicast Routes
Static unicast routes are user-defined routes that cause packets moving between a source and a
destination to take a specified path. Static routes can be important if the router cannot build a route to a
particular destination and are useful for specifying a gateway of last resort to which all unroutable
packets are sent.
Beginning in privileged EXEC mode, follow these steps to configure a static route:
Use the
no ip route
prefix mask
{
address
|
interface
} global configuration command to remove a static
route.
The switch retains static routes until you remove them. However, you can override static routes with
dynamic routing information by assigning administrative distance values. Each dynamic routing
protocol has a default administrative distance, as listed in
Table 34-5
. If you want a static route to be
overridden by information from a dynamic routing protocol, set the administrative distance of the static
route higher than that of the dynamic protocol.
Static routes that point to an interface are advertised through RIP, whether or not static
redistribute
router configuration commands were specified for those routing protocols. These static routes are
advertised because static routes that point to an interface are considered in the routing table to be
connected and hence lose their static nature. However, if you define a static route to an interface that is
not one of the networks defined in a network command, no dynamic routing protocols advertise the route
unless a
redistribute
static command is specified for these protocols.
When an interface goes down, all static routes through that interface are removed from the IP routing
table. When the software can no longer find a valid next hop for the address specified as the forwarding
router's address in a static route, the static route is also removed from the IP routing table.
Command
Purpose
Step 1
configure terminal
Enter global configuration mode.
Step 2
ip route
prefix mask
{
address
|
interface
} [
distance
]
Establish a static route.
Step 3
end
Return to privileged EXEC mode.
Step 4
show ip route
Display the current state of the routing table to verify
the configuration.
Step 5
copy running-config startup-config
(Optional) Save your entries in the configuration file.
Table 34-5
Dynamic Routing Protocol Default Administrative Distances
Route Source
Default Distance
Connected interface
0
Static route
1
Unknown
225
