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
Section titled “Diagram”Classes
Section titled “Classes”configuration (nxos.devices)
Section titled “configuration (nxos.devices)”| Name | Type | Constraint | Mandatory | Default Value |
|---|---|---|---|---|
| ipv6_prefix_lists | List | [ipv6_prefix_lists] | No |
ipv6_prefix_lists (nxos.devices.configuration)
Section titled “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)
Section titled “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
Section titled “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: 128Example 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: ::/0Example 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