IP Routing: OSPF Configuration Guide, Cisco IOS Release 15S
OSPFv3 ABR Type 3 LSA Filtering
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OSPFv3 ABR Type 3 LSA Filtering

OSPFv3 ABR Type 3 LSA Filtering

This feature extends the ability of an Area Border Router (ABR) that is running the Open Shortest Path First version 3 (OSPFv3) protocol to filter type 3 link-state advertisements (LSAs) that are sent between different OSPFv3 areas. This feature allows only packets with specified prefixes to be sent from one area to another area and restricts all packets with other prefixes. This type of area filtering can be applied out of a specific OSPFv3 area, into a specific OSPFv3 area, or into and out of the same OSPFv3 areas at the same time.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table at the end of this module.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

OSPFv3 ABR Type 3 LSA Filtering

Only type 3 LSAs that originate from an ABR are filtered.

Information About OSPFv3 ABR Type 3 LSA Filtering

Area Filter Support

OSPFv3 area filters allow the filtering of inter-area prefix LSAs on the ABRs. The filter, based on IPv6 prefix lists, can be applied in both directions. In the “in” direction, it filters out the LSAs coming from all other areas when sending the inter-area prefix LSAs into the specified area. In the “out” direction, it filters out the inter-area prefix LSAs generated for the specified area.

The Area Filter Support feature gives the administrator improved control of route distribution between OSPFv3 areas.

How to Configure OSPFv3 ABR Type 3 LSA Filtering

Configuring Area Filter Support for OSPFv3

SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    router ospfv3 process-id

    4.    area area-id filter-list prefix prefix-list-name {in | out}

    5.    end

    6.    ipv6 prefix-list list-name [seq seq-number] {deny ipv6-prefix/prefix-length | permit ipv6-prefix/prefix-length | description text} [ge ge-value] [le le-value]


DETAILED STEPS
     Command or ActionPurpose
    Step 1 enable


    Example:
    Device> enable
     

    Enables privileged EXEC mode.

    • Enter your password if prompted.
     
    Step 2 configure terminal


    Example:
    Device# configure terminal
     

    Enters global configuration mode.

     
    Step 3 router ospfv3 process-id


    Example:
    Device(config)# router ospfv3 1
    
     

    Configures the router to run an OSPFv3 process.

     
    Step 4 area area-id filter-list prefix prefix-list-name {in | out}


    Example:
    Device(config-router)# area 1 filter-list prefix test_ipv6 out
     

    Configures the router to filter interarea routes out of the specified area.

     
    Step 5 end


    Example:
    Device(config-router)# end
     

    Returns to global configuration mode.

     
    Step 6ipv6 prefix-list list-name [seq seq-number] {deny ipv6-prefix/prefix-length | permit ipv6-prefix/prefix-length | description text} [ge ge-value] [le le-value]


    Example:
    Device(config)# ipv6 prefix-list test_ipv6 seq 5 permit 2011::1/128 
     

    Creates a prefix list with the name specified for the list-name argument.

     

    Configuration Examples for OSPFv3 ABR Type 3 LSA Filtering

    Example: Area Filter Support for OSPFv3

    The following example shows how to configure Area Filter Support for OSPFv3:

    router ospfv3 1
    !
    address-family ipv4 unicast
     area 2 filter-list prefix test_ipv4 in
    exit-address-family
    !
    address-family ipv6 unicast
     area 2 filter-list prefix test_ipv6 in 
    exit-address-family
    !
    ip prefix-list test_ipv4 seq 5 permit 2.2.2.2/32 
    ! 
    ! 
    ipv6 prefix-list test_ipv6 seq 5 deny 2011::1/128 
    
    

    Additional References for OSPFv3 ABR Type 3 LSA Filtering

    Related Documents

    Related Topic

    Document Title

    Configuring OSPF

    “Configuring OSPF”

    OSPF commands

    Cisco IOS IP Routing: OSPF Command Reference

    Cisco IOS master command list, all releases

    Cisco IOS Master Command List, All Releases

    Standards

    Standard

    Title

    No new or modified standards are supported and support for existing standards has not been modified.

    RFCs

    RFC

    Title

    No new or modified RFCs are supported and support for existing RFCs has not been modified.

    Technical Assistance

    Description

    Link

    The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

    http:/​/​www.cisco.com/​cisco/​web/​support/​index.html

    Feature Information for OSPFv3 ABR Type 3 LSA Filtering

    The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

    Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

    Table 1 Feature Information for OSPFv3 ABR Type 3 LSA Filtering

    Feature Name

    Releases

    Feature Information

    OSPFv3 ABR Type 3 LSA Filtering

    Cisco IOS XE Release 3.8

    15.3(1)S

    15.2(1)E

    The OSPFv3 ABR Type 3 LSA Filtering feature extends the ability of an ABR that is running the OSPFv3 protocol to filter type 3 LSAs that are sent between different OSPFv3 areas. This feature allows only packets with specified prefixes to be sent from one area to another area and restricts all packets with other prefixes. This type of area filtering can be applied out of a specific OSPFv3 area, into a specific OSPFv3 area, or into and out of the same OSPFv3 areas at the same time.