R211x-HP Flexfabric 11900 Layer 3 - IP Routing Command Reference

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Usage guidelines
Prefix prioritization enables the device to install prefixes in descending priority order: critical, high,
medium, and low. The prefix priorities are assigned through routing policies. When a route is assigned
multiple prefix priorities, it uses the highest priority.
By default, the 32-bit OSPF host routes have a medium priority and other routes have a low priority.
Examples
# Use a routing policy to assign the medium priority to the specified route prefixes.
<Sysname> system-view
[Sysname] ip prefix-list test index 10 permit 100.1.1.0 24
[Sysname] route-policy pre permit node 10
[Sysname-route-policy-pre-10] if-match ip address prefix-list test
[Sysname-route-policy-pre-10] apply prefix-priority medium
[Sysname-route-policy-pre-10] quit
[Sysname] ospf 100
[Sysname-ospf-100] prefix-priority route-policy pre
prefix-suppression
Use prefix-suppression to disable an OSPF process from advertising all IP prefixes except for the prefixes
of loopback interfaces, secondary IP addresses, and passive interfaces.
Use undo prefix-suppression to restore the default.
Syntax
prefix-suppression
undo prefix-suppression
Default
An OSPF process advertises all prefixes.
Views
OSPF view
Predefined user roles
network-admin
mdc-admin
Usage guidelines
If you want to use prefix suppression, HP recommends that you configure prefix suppression on all OSPF
routers.
To disable an OSPF process from advertising the prefixes of loopback interfaces and passive interfaces,
configure prefix suppression on the interfaces by using the ospf prefix-suppression command.
When prefix suppression is enabled:
• On P2P and P2MP networks, OSPF does not advertise Type-3 links in Router LSAs. Other routing
information can still be advertised to ensure traffic forwarding.
• On broadcast and NBMA networks, the DR generates Network LSAs with a mask length of 32 to
suppress network routes. Other routing information can still be advertised to ensure traffic