Configuring A Loopback Interface - Cisco 3845 - Security Bundle Router Software Manual

Configuring OSPF
Beginning in privileged EXEC mode, follow these steps to configure OSPF LSA pacing:
Command
Step 1
configure terminal
Step 2
router ospf process-id
Step 3
timers lsa-group-pacing seconds
Step 4
end
Step 5
show running-config
Step 6
copy running-config startup-config
To return to the default value, use the no timers lsa-group-pacing router configuration command.

Configuring a Loopback Interface

OSPF uses the highest IP address configured on the interfaces as its router ID. If this interface is down
or removed, the OSPF process must recalculate a new router ID and resend all its routing information
out its interfaces. If a loopback interface is configured with an IP address, OSPF uses this IP address as
its router ID, even if other interfaces have higher IP addresses. Because loopback interfaces never fail,
this provides greater stability. OSPF automatically prefers a loopback interface over other interfaces, and
it chooses the highest IP address among all loopback interfaces.
Beginning in privileged EXEC mode, follow these steps to configure a loopback interface:
Command
Step 1
configure terminal
Step 2
interface loopback 0
Step 3
ip address address mask
Step 4 end
Step 5 show ip interface
Step 6 copy running-config startup-config
Use the no interface loopback 0 global configuration command to disable the loopback interface.
Cisco ME 3800X and 3600X Switch Software Configuration Guide
29-32
Purpose
Enter global configuration mode.
Enable OSPF routing, and enter router configuration mode.
Change the group pacing of LSAs.
Return to privileged EXEC mode.
Verify your entries.
(Optional) Save your entries in the configuration file.
Purpose
Enter global configuration mode.
Create a loopback interface, and enter interface configuration mode.
Assign an IP address to this interface.
Return to privileged EXEC mode.
Verify your entries.
(Optional) Save your entries in the configuration file.
Chapter 29 Configuring IP Unicast Routing
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