Support for IPv6 Networks in Contrail
Starting with Contrail Release 2.0, support for IPv6 overlay networks is provided.
Overview: IPv6 Networks in Contrail
The following features are supported for IPv6 networks and overlay. The underlay network must be IPv4.
Virtual machines with IPv6 and IPv4 interfaces
Virtual machines with IPv6-only interfaces
DHCPv6 and neighbor discovery
Policy and Security groups
IPv6 flow set up, tear down, and aging
Flow set up and tear down based on TCP state machine
Protocol-based flow aging
Fat flow
Allowed address pair configuration with IPv6 addresses
IPv6 service chaining
Equal Cost Multi-Path (ECMP)
Connectivity with gateway (MX Series device)
Virtual Domain Name Services (vDNS), name-to-IPv6 address resolution
User-Visible Entities (UVEs)
NOT present is support for the following:
Source Network Address Translation (SNAT)
Load Balancing as a Service (LBaaS)
IPv6 fragmentation
Floating IP
Link-local and metadata services
Diagnostics for IPv6
Contrail Device Manager
Virtual customer premises equipment (vCPE)
Creating IPv6 Virtual Networks in Contrail
You can create an IPv6 virtual network from the Contrail user interface in the same way you create an IPv4 virtual network. When you create a new virtual network by selecting Configure > Networking > Networks, the Edit fields accept IPv6 addresses, as shown in the following image.
Address Assignments
When virtual machines are launched with an IPv6 virtual network created in the Contrail user interface, the virtual machine interfaces get assigned addresses from all the families configured in the virtual network.
The following is a sample of IPv6 instances with address assignments, as listed in the OpenStack Horizon user interface.
Enabling DHCPv6 In Virtual Machines
To allow IPv6 address assignment using DHCPv6, the virtual machine network interface configuration must be updated appropriately.
For example, to enable DHCPv6 for Ubuntu-based virtual machines, add the following line in the /etc/network/interfaces file:
iface eht0 inet6 dhcp
Also, dhclient -6
can be run from
within the virtual machine to get IPv6 addresses using DHCPv6.
Adding IPv6 Peers
The procedure to add an IPv6 BGP peer in Contrail is similar
to adding an IPv4 peer. Select Configure > Infrastructure > BGP
Peers, include inet6-vpn
in the Address
Family list to allow advertisement of IPv6 addresses.
A sample is shown in the following.
Additional configuration is required on the peer router to allow inet6-vpn peering.