IPv6 Prefix List

IPv6 prefix lists provide ordered sets of permit/deny rules for filtering IPv6 routes based on network prefix and prefix length, serving as a fundamental building block for IPv6 routing policy on NX-OS. Each entry supports exact match or range-based matching with configurable minimum and maximum prefix lengths, enabling precise control over which IPv6 routes are accepted or advertised by routing protocols. IPv6 prefix lists are commonly referenced by route maps and other routing policy constructs to implement granular IPv6 route filtering and traffic engineering.

Diagram

Classes

nxos

Name	Type	Constraint	Mandatory	Default Value
devices	List	devices	No
device_groups	List	device_groups	No
global	Class	global	No
templates	List	templates	No

devices (nxos)

Name	Type	Constraint	Mandatory	Default Value
configuration	Class	configuration	No

device_groups (nxos)

Name	Type	Constraint	Mandatory	Default Value
configuration	Class	configuration	No

global (nxos)

Name	Type	Constraint	Mandatory	Default Value
configuration	Class	configuration	No

templates (nxos)

Name	Type	Constraint	Mandatory	Default Value
configuration	Class	configuration	No

configuration (nxos.devices)

Name	Type	Constraint	Mandatory	Default Value
ipv6_prefix_lists	List	ipv6_prefix_lists	No

ipv6_prefix_lists (nxos.devices.configuration)

Name	Type	Constraint	Mandatory	Default Value
name	String		Yes
description	String		No
entries	List	entries	No

entries (nxos.devices.configuration.ipv6_prefix_lists)

Name	Type	Constraint	Mandatory	Default Value
seq	Integer		Yes
action	Choice	permit, deny	No
prefix	IP		No
mask	Integer	min: 0, max: 128	No
ge	Integer	min: 0, max: 128	No
le	Integer	min: 0, max: 128	No

Examples

Example 1: Simple IPv6 prefix list to match loopback addresses

nxos:
  devices:
    - name: SPINE1
      configuration:
        ipv6_prefix_lists:
          - name: PLV6-LOOPBACKS
            description: "Match all fabric IPv6 loopback /128 addresses"
            entries:
              - seq: 10
                action: permit
                prefix: 2001:db8:1::/48
                ge: 128
                le: 128

Example 2: Multiple IPv6 prefix lists for BGP route filtering

nxos:
  devices:
    - name: LEAF1
      configuration:
        ipv6_prefix_lists:
          - name: PLV6-TENANT-NETS
            description: "Permit tenant IPv6 prefixes"
            entries:
              - seq: 10
                action: permit
                prefix: 2001:db8:100::/48
              - seq: 20
                action: permit
                prefix: 2001:db8:200::/48
          - name: PLV6-DEFAULT-ONLY
            description: "Permit IPv6 default route only"
            entries:
              - seq: 10
                action: permit
                prefix: ::/0

Example 3: IPv6 prefix list with range matching for route aggregation policy

nxos:
  devices:
    - name: BORDER-LEAF1
      configuration:
        ipv6_prefix_lists:
          - name: PLV6-EXTERNAL-PREFIXES
            description: "Accept external IPv6 routes between /32 and /64"
            entries:
              - seq: 10
                action: deny
                prefix: fc00::/7
              - seq: 20
                action: permit
                prefix: ::/0
                ge: 32
                le: 64