H3C Technologies H3C S5560 Series Switches - Manual (Page 98)

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Configuring OSPF preference
A router can run multiple routing protocols, and each protocol is assigned a preference. If multiple routes
are available to the same destination, the one with the highest protocol preference is selected as the best
route.
To configure OSPF preference:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter OSPF view.
ospf [ process-id | router-id router-id
| vpn-instance vpn-instance-name ] *
N/A
3. Configure a
preference for OSPF.
preference [ ase ] [ route-policy
route-policy-name ] value
By default, the preference of OSPF
internal routes is 10 and the preference
of OSPF external routes is 150.
Configuring OSPF route redistribution
On a router running OSPF and other routing protocols, you can configure OSPF to redistribute routes
from other protocols, such as RIP, IS-IS, BGP, static, and direct, and advertise them in Type-5 LSAs or
Type-7 LSAs. In addition, you can configure OSPF to filter redistributed routes so that OSPF advertises
only permitted routes.
IMPORTANT:
The import-route bgp command redistributes only EBGP routes. Because the import-route bgp
allow-ibgp command redistributes both EBGP and IBGP routes, and mi
ght cause routing loops, use it with
caution.
Redistributing routes from another routing protocol
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter OSPF view.
ospf [ process-id | router-id router-id |
vpn-instance vpn-instance-name ] *
N/A
3. Configure OSPF to
redistribute routes from
another routing protocol.
import-route protocol [ process-id |
all-processes | allow-ibgp ]
[ allow-direct | cost cost | nssa-only |
route-policy route-policy-name | tag tag
| type type ] *
By default, no route redistribution
is configured.
This command redistributes only
active routes. To view information
about active routes, use the
display ip routing-table protocol
command.
4. (Optional.) Configure
OSPF to filter redistributed
routes.
filter-policy { acl-number | prefix-list
prefix-list-name } export [ protocol
[ process-id ] ]
By default, OSPF accepts all
redistributed routes.