Configure OSPF filter rules

Configure OSPF filter rules to improve control of route distribution between OSPF areas by allowing only specified prefixes to be sent from one area to another area while restricting all other prefixes.

You can configure ABR Type 3 LSA filters for each OSPF process. ABR Type 3 LSA filters allow only specified prefixes to be sent from one area to another area and restrict all other prefixes. You can apply this type of area filtering out of a specific OSPF area, into a specific OSPF area, or into and out of the same OSPF area at the same time. OSPF ABR Type 3 LSA filtering improves your control of route distribution between OSPF areas.

Procedure

Step 1

Choose Devices > Device Management, and edit the Firewall Threat Defense device.

Step 2

Click Routing.

Step 3

(For a virtual-router-aware device) From the virtual routers drop-down list, choose the virtual router for which you are configuring OSPF.

Step 4

Click OSPF.

Step 5

Select Filter Rule > Add.

You can click Edit (edit icon), or use the right-click menu to cut, copy, past, insert, and delete filter rules.

Step 6

Configure the following filter rule options for each OSPF process:

  • OSPF Process— For a device using virtual routing, the drop-down lists the unique process IDs generated for the selected virtual router.

  • Access List—The access list for this OSPF process. To add a new standard access list object, click Add (add icon) and see Configure Standard ACL Objects.

  • Traffic Direction—Choose In or Out for the traffic direction being filtered. Choose In to filter LSAs coming into an OSPF area, or Out to filter LSAs coming out of an OSPF area. If you are editing an existing filter entry, you cannot modify this setting.

  • Interface—The interface for this filter rule.

Step 7

Click OK to save the filter rule configuration.

Step 8

Click Save on the Routing page to save your changes.

The OSPF filter rules are configured and saved, enabling controlled route distribution between OSPF areas based on the specified access list and traffic direction settings.

What to do next

Continue with Configure OSPF summary addresses.