Configuring a VXLANv6 Fabric

This chapter describes how to configure a VXLAN fabric with IPv6 underlay.

Overview

From Cisco NDFC, you can create an Easy fabric with IPv6 only underlay. The IPv6 underlay is supported only for the Easy_Fabric template. In the IPv6 underlay fabric, intra-fabric links, routing loopback, vPC peer link SVI, and NVE loopback interface for VTEP are configured with IPv6 addresses. EVPN BGP neighbor peering is also established using IPv6 addressing.

The following guidelines are applicable for IPv6 underlay:

  • IPv6 underlay is supported for the Cisco Nexus 9000 Series switches with Cisco NX-OS Release 9.3(1) or higher.

  • VXLANv6 is only supported Cisco Nexus 9332C, Cisco Nexus C9364C, and Cisco Nexus modules that end with EX, GX, FX, FX2, FX3, or FXP.


    Note

    VXLANv6 is defined as a VXLAN fabric with IPv6 underlay.

  • In VXLANv6, the platforms supported on spine are all Nexus 9000 Series and Nexus 3000 Series platforms.

  • The overlay routing protocol supported for the IPv6 fabric is BGP EVPN.

  • vPC with physical multichassis EtherChannel trunk (MCT) feature is supported for the IPv6 underlay network in NDFC. The vPC peer keep-alive can be loopback or management with IPv4 or IPv6 address.

  • Brownfield migration is supported for the VXLANv6 fabrics. Note that L3 vPC keep-alive using IPv6 address is not supported for brownfield migration. This vPC configuration is deleted after the migration. However, L3 vPC keep-alive using IPv4 address is supported.

  • DHCPv6 is supported for the IPv6 underlay network.

  • The following features are not supported for VXLAN IPv6 underlay:

    • Multicast underlay

    • Tenant Routed Multicast (TRM)

    • ISIS, OSPF, and BGP authentication

    • VXLAN Multi-Site

    • Dual stack underlay

    • vPC Fabric Peering

    • DCI SR-MPLS or MPLS-LDP handoff

    • BFD

    • Super Spine switch roles

    • NGOAM

Creating a VXLAN Fabric with IPv6 Underlay

This procedure shows how to create a VXLAN BGP EVPN fabric with IPv6 underlay. Only the fields for creating a VXLAN fabric with IPv6 underlay are documented. For information about the remaining fields, see Creating a New VXLAN BGP EVPN Fabric.

Procedure

Step 1

Choose LAN > Fabrics.

Step 2

From the Actions drop-down list, choose Create Fabric.

The Create Fabric window appears.

  • Fabric Name - Enter the name of the fabric.

  • Fabric Template - From the drop-down list, choose the Easy_Fabric fabric template.

Step 3

The General Parameters tab is displayed by default. The fields in this tab are:

BGP ASN: Enter the BGP AS number for the fabric. You can enter either the 2 byte BGP ASN or 4 byte BGP ASN.

Enable IPv6 Underlay: Check the Enable IPv6 Underlay check box .

Enable IPv6 Link-Local Address: Check the Enable IPv6 Link-Local Address check box to use the link local addresses in the fabric between leaf-spine and spine-border interfaces. If you check this check box, the Underlay Subnet IPv6 Mask field is not editable. By default, the Enable IPv6 Link-Local Address field is enabled.

IPv6 underlay supports only the p2p networks. Therefore, the Fabric Interface Numbering drop-down list field is disabled.

Underlay Subnet IPv6 Mask: Specify the subnet mask for the fabric interface IPv6 addresses.

Underlay Routing Protocol: The IGP used in the fabric, that is, OSPFv3 or IS-IS for VXLANv6.

Step 4

Click the Replication tab.

IPv6 underlay supports only the ingress replication mode.

All the fields under this tab are disabled.
Step 5

Click the VPC tab.

vPC Peer Keep Alive option – Choose the management or loopback option. If you want to use IP addresses assigned to the management port and the management VRF, choose management. If you use IP addresses assigned to loopback interfaces (and a non-management VRF), choose loopback. Both the options are supported for IPv6 underlay.

Step 6

Click the Protocols tab.

Underlay Anycast Loopback Id: Specify the underlay anycast loopback ID for IPv6 underlay. Since an IPv6 address cannot be configured as secondary, an additional loopback interface is allocated on each vPC device. Its IPv6 address will be used as the VIP.

Step 7

Click the Resources tab.

Manual Underlay IP Address Allocation: Check the Manual Underlay IP Address Allocation check box to manually allocate underlay IP addresses. The dynamic underlay IP addresses fields are disabled.

Underlay Routing Loopback IPv6 Range: Specify loopback IPv6 addresses for the protocol peering.

Underlay VTEP Loopback IPv6 Range: Specify loopback IPv6 addresses for VTEPs. The IPv6 address for anycast will be assigned from this range.

Underlay Subnet IPv6 Range: Specify the IPv6 address range that is used for assigning IP addresses for numbered and peer link SVIs. To edit this field, you need to uncheck the Enable IPv6 Link-Local Address check box under the General Parameters tab.

BGP Router ID Range for IPv6 Underlay: Specify the address range to assign the BGP Router IDs.

Step 8

Click the Bootstrap tab.

Enable Bootstrap: Check the Enable Bootstrap checkbox.

Enable Local DHCP Server: Check the Enable Local DHCP Server check box to initiate enabling of automatic IP address assignment through the local DHCP server. When you check this check box, the DHCP Scope Start Address and DHCP Scope End Address fields become editable.

DHCP Version: Choose DHCPv4 from the drop-down list.

For information about the remaining tabs and fields, see Creating a New VXLAN BGP EVPN Fabric.

What to do next

Adding Switches to a Fabric