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3Com Switch 7750 Series
Command Reference Guide – Routing Protocol Chapter 3 OSPF Configuration Commands
3-33
[3Com-acl-basic-2000] rule deny source any
[3Com-ospf-1] filter-policy 2000 export
3.1.26 filter-policy import
Syntax
filter-policy { acl-number | ip-prefix ip-prefix-name | gateway prefix-list-name }
import
undo filter-policy { acl-number | ip-prefix ip-prefix-name | gateway ip-prefix-name }
import
View
OSPF view
Parameter
acl-number: Basic or advanced Access control list used for filtering the destination
addresses of the routing information.
ip-prefix-name: Name of the address prefix list used for filtering the destination
addresses of the routing information, containing 1 to 19 characters.
gateway ip-prefix-name: Specifies the name of the address prefix list used for filtering
the addresses of the neighbor routers advertising the routing information.
Description
Use the filter-policy import command to configure the OSPF rules for filtering the
routing information received.
Use the undo filter-policy import command to cancel the filtering of the routing
information received.
By default, no filtering of the received routing information is performed.
In some cases, it may be required that only the routing information meeting some
conditions can be received. You can use the filter-policy command to set the filtering
conditions for the routing information to be received. Only the routing information
passing the filter can be received.
The filter-policy import command filters the routes calculated by OSPF. Only the
routes passing the filter can be added to the routing table. The routes can be filtered
based on next hop and destination address.
OSPF is a dynamic routing protocol based on link state, with routing information
hidden in LSAs. Therefore, OSPF cannot filter any advertised or received LSA. This
command is used much less in OSPF than in distance-vector routing protocols.