3Com 5500-SI Configuration Manual page 251

Configuring OSPF Route Filtering
Perform the following configuration in OSPF View.
Configuring OSPF to Filter the Received Routes
Table 245 Enabling OSPF to filter the received routes
Operation
Disable to filter the received global
routing information
Cancel to filter the received global
routing information
Configuring OSPF to filter the distributed routes
Table 246 Enabling OSPF to filter the distributed routes
Operation
Enable OSPF to filter the distributed
routes
Disable OSPF to filter the distributed
routes
By default, OSPF will not filter the imported and distributed routing information.
The
■ filter-policy import
received from the neighbors, and routes that cannot pass the filter will not be
added to the routing table. This command only takes effect on ABR.
The
■ filter-policy export
by the
import-route
filter-policy export
command to import other external routes (including OSPF routes of different
process), then the
filter-policy export
Configuring the Filling of the MTU Field When an Interface Transmits DD
Packets
OSPF-running routers use the DD (Database Description) packets to describe their
own LSDBs when synchronizing the databases.
You can manually specify an interface to fill in the MTU field in a DD packet when it
transmits the packet. The MTU should be set to the real MTU on the interface.
Perform the following configuration in Interface View:
Table 247 Configuring the Filling of the MTU Field when an Interface Transmits DD Packets
Operation
Enable an interface to fill in the MTU field when
transmitting DD packets
Disable the interface to fill MTU when transmitting DD
packets
By default, the interface does not fill in the MTU field when transmitting DD packets,
and the MTU in the DD packets is 0.
Command
filter-policy { acl_number | ip-prefix
ip_prefix_name | gateway ip_prefix_name }
import
undo filter-policy { acl_number | ip-prefix
ip_prefix_name | gateway ip_prefix_name }
import
Command
filter-policy { acl_number | ip-prefix
ip_prefix_name } export [ routing_ process
]
undo filter-policy { acl_number | ip-prefix
ip_prefix_name } export [ routing_process ]
command only filters the OSPF routes of this process
command only takes effect to the routes imported
command. If you configure the Switch with only the
command, but without configuring the
command does not take effect.
OSPF Configuration 251
import-route
Command
ospf mtu-enable
undo ospf mtu-enable