Configure an IPv6 Prefix List

Use IPv6 prefix lists to allow or deny specific IPv6 route updates. A prefix list policy specifies route prefixes to match. When there is a match, the route is used.

About this task

You configure prefix lists on a VRF instance the same way you configure the GlobalRouter, except that you must use VRF Router Configuration mode.

Procedure

  1. Enter Global Configuration mode:

    enable

    configure terminal

  2. Create an IPv6 prefix list:

    ipv6 prefix-list <WORD 1-64> <WORD 1–256> [ge <0–128>] [le <0–128>] [id <1-2147483647>]

    Use the same command to add additional prefixes to the list.

  3. To rename the list:

    ipv6 prefix-list <WORD 1–64> name <WORD 1–64>

  4. Display the prefix list:

    show ipv6 prefix-list <WORD 1–256> [vrf WORD<1-16>] [vrfids WORD<1-512>] [WORD <1-64>]

Example

Create an IPv6 prefix list:

Switch:1<config>#ipv6 prefix-list list4 2001:DB8::/32  ge 32 le 32

To rename the list:

Switch:1<config>#ipv6 prefix-list list4 name list5

Variable Definitions

Use the data in the following table to use the ipv6 prefix-list command.

Variable

Value

<WORD 1–64>

Specifies the IPv6 prefix-list name.

<WORD 1–256>

Specifies the IPv6 prefix and length.

ge <0–128>

Specifies the minimum length to match.

Lower bound and higher bound mask lengths together can define a range of networks.

id <1-2147483647>

Specifies the Prefix list ID.

le <0–128>

Specifies the maximum length to match.

Lower bound and higher bound mask lengths together can define a range of networks.

name <WORD 1–64>

Names the prefix list. The default value is none.

Use the data in the following table to use the show ipv6 prefix-list command.

Variable

Value

<WORD 1–256>

Specifies the IPv6 prefix and length.

vrf WORD<1-16>

Specifies the name of the VRF.

vrfids WORD<0-512>

Specifies the ID of the VRF and is an integer in the range of 0–512.

WORD<1-64>

Specifies a prefix list, by name, to use for the command output.