HP 3500YL - Manual (Page 246)

IP Routing Features
Configuring OSPF
Syntax: interface loopback <0-7># ip ospf < lo-ip-address > cost < number >
Executed in a specific loopback context to modify the cost used
to advertise the loopback address (and subnet) to the area
border router (ABR). Requires that the specified loopback
interface is already configured with an IP address on the
switch.
loopback interface <0-7>: Defines the loopback context for
executing the cost assignment.
ip ospf < lo-ip-address >: Specifies the loopback interface by its
IP address.
cost < number >: Specifies a number that represents the
administrative metric associated with the loopback interface.
Valid values are from 1 to 65535. Default: 1
.
Example: To configure a cost of 10 for advertising the IP address 172.16.112.2
configured for loopback interface 3 in an OSPF area 192.5.0.0, enter the
following commands:
ProCurve(config)# interface loopback 3
ProCurve(lo-3)# ip ospf 172.16.112.2 area 192.5.0.0
ProCurve(lo-3)# ip ospf 172.16.112.2 cost 10
OSPF Redistribution of Loopback Addresses: When you assign a loopback
address to an OSPF area, the route redistribution of the loopback address is
limited to the specified area.
When route redistribution is enabled:
■ The switch advertises a loopback IP address that is not assigned to an
OSPF area as an OSPF external route to its OSPF neighbors, and handles
it as a connected route.
■ The switch advertises a loopback address that is assigned to an OSPF area
as an OSPF internal route.
To enable redistribution of loopback IP addresses in OSPF, enter the redistri­
bution connected command as described in “2. Enable Route Redistribution”
on page 5-74.
Example: In the following configuration, the loopback IP address 13.3.4.5 of
loopback 2 is advertised only in OSPF area 0.0.0.111. The IP addresses 14.2.3.4
and 15.2.3.4 of loopback 1 are advertised in all OSPF areas.
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