Chapter 16. Tenant networking with IPv6 16.1. Overview of project networking This chapter contains information about implementing IPv6 subnets in a Red Hat OpenStack Platform (RHOSP) project network. In addition to project networking, with RHOSP director, you can configure IPv6-native deployments for the overcloud nodes. RHOSP supports IPv6 in project networks. IPv6 subnets are created within existing project networks, and support a number of address assignment modes: Stateless Address Autoconfiguration (SLAAC) , Stateful DHCPv6 , and Stateless DHCPv6 . 16.2. IPv6 subnet options Create IPv6 subnets using the openstack subnet create command. You can also specify the address mode and the Router Advertisement mode. Use the following list to understand the possible combinations of options that you can include with the openstack subnet create command. RA Mode Address Mode Result ipv6_ra_mode=not set ipv6-address-mode=slaac The instance receives an IPv6 address from the external router (not managed by OpenStack Networking) using SLAAC . ipv6_ra_mode=not set ipv6-address-mode=dhcpv6-stateful The instance receives an IPv6 address and optional information from OpenStack Networking (dnsmasq) using DHCPv6 stateful . ipv6_ra_mode=not set ipv6-address-mode=dhcpv6-stateless The instance receives an IPv6 address from the external router using SLAAC, and optional information from OpenStack Networking (dnsmasq) using DHCPv6 stateless . ipv6_ra_mode=slaac ipv6-address-mode=not-set The instance uses SLAAC to receive an IPv6 address from OpenStack Networking ( radvd ). ipv6_ra_mode=dhcpv6-stateful ipv6-address-mode=not-set The instance receives an IPv6 address and optional information from an external DHCPv6 server using DHCPv6 stateful . ipv6_ra_mode=dhcpv6-stateless ipv6-address-mode=not-set The instance receives an IPv6 address from OpenStack Networking ( radvd ) using SLAAC, and optional information from an external DHCPv6 server using DHCPv6 stateless . ipv6_ra_mode=slaac ipv6-address-mode=slaac The instance receives an IPv6 address from OpenStack Networking ( radvd ) using SLAAC . ipv6_ra_mode=dhcpv6-stateful ipv6-address-mode=dhcpv6-stateful The instance receives an IPv6 address from OpenStack Networking ( dnsmasq ) using DHCPv6 stateful , and optional information from OpenStack Networking ( dnsmasq ) using DHCPv6 stateful . ipv6_ra_mode=dhcpv6-stateless ipv6-address-mode=dhcpv6-stateless The instance receives an IPv6 address from OpenStack Networking ( radvd ) using SLAAC , and optional information from OpenStack Networking ( dnsmasq ) using DHCPv6 stateless . 16.3. Create an IPv6 subnet using Stateful DHCPv6 Complete the steps in this procedure to create an IPv6 subnet in a project network using some of the options in section 17.1. First, gather the necessary project and network information, then include this information in the openstack subnet create command. Note OpenStack Networking supports only EUI-64 IPv6 address assignment for SLAAC. This allows for simplified IPv6 networking, as hosts self-assign addresses based on the base 64-bits plus the MAC address. You cannot create subnets with a different netmask and address_assign_type of SLAAC. Retrieve the project ID of the Project where you want to create the IPv6 subnet. These values are unique between OpenStack deployments, so your values differ from the values in this example. Retrieve a list of all networks present in OpenStack Networking (neutron), and note the name of the network that you want to host the IPv6 subnet: Include the project ID and network name in the openstack subnet create command: Validate this configuration by reviewing the network list. Note that the entry for database-servers now reflects the newly created IPv6 subnet: As a result of this configuration, instances that the QA project creates can receive a DHCP IPv6 address when added to the database-servers subnet:

Commands:
openstack project list +----------------------------------+----------+ | ID | Name | +----------------------------------+----------+ | 25837c567ed5458fbb441d39862e1399 | QA | | f59f631a77264a8eb0defc898cb836af | admin | | 4e2e1951e70643b5af7ed52f3ff36539 | demo | | 8561dff8310e4cd8be4b6fd03dc8acf5 | services | +----------------------------------+----------+
openstack network list +--------------------------------------+------------------+-------------------------------------------------------------+ | id | name | subnets | +--------------------------------------+------------------+-------------------------------------------------------------+ | 8357062a-0dc2-4146-8a7f-d2575165e363 | private | c17f74c4-db41-4538-af40-48670069af70 10.0.0.0/24 | | 31d61f7d-287e-4ada-ac29-ed7017a54542 | public | 303ced03-6019-4e79-a21c-1942a460b920 172.24.4.224/28 | | 6aff6826-4278-4a35-b74d-b0ca0cbba340 | database-servers | | +--------------------------------------+------------------+-------------------------------------------------------------+
openstack subnet create --ip-version 6 --ipv6-address-mode dhcpv6-stateful --project 25837c567ed5458fbb441d39862e1399 --network database-servers --subnet-range fdf8:f53b:82e4::53/125 subnet_name Created a new subnet: +-------------------+--------------------------------------------------------------+ | Field | Value | +-------------------+--------------------------------------------------------------+ | allocation_pools | {"start": "fdf8:f53b:82e4::52", "end": "fdf8:f53b:82e4::56"} | | cidr | fdf8:f53b:82e4::53/125 | | dns_nameservers | | | enable_dhcp | True | | gateway_ip | fdf8:f53b:82e4::51 | | host_routes | | | id | cdfc3398-997b-46eb-9db1-ebbd88f7de05 | | ip_version | 6 | | ipv6_address_mode | dhcpv6-stateful | | ipv6_ra_mode | | | name | | | network_id | 6aff6826-4278-4a35-b74d-b0ca0cbba340 | | tenant_id | 25837c567ed5458fbb441d39862e1399 | +-------------------+--------------------------------------------------------------+
openstack network list +--------------------------------------+------------------+-------------------------------------------------------------+ | id | name | subnets | +--------------------------------------+------------------+-------------------------------------------------------------+ | 6aff6826-4278-4a35-b74d-b0ca0cbba340 | database-servers | cdfc3398-997b-46eb-9db1-ebbd88f7de05 fdf8:f53b:82e4::50/125 | | 8357062a-0dc2-4146-8a7f-d2575165e363 | private | c17f74c4-db41-4538-af40-48670069af70 10.0.0.0/24 | | 31d61f7d-287e-4ada-ac29-ed7017a54542 | public | 303ced03-6019-4e79-a21c-1942a460b920 172.24.4.224/28 | +--------------------------------------+------------------+-------------------------------------------------------------+
openstack server list +--------------------------------------+------------+--------+------------+-------------+-------------------------------------+ | ID | Name | Status | Task State | Power State | Networks | +--------------------------------------+------------+--------+------------+-------------+-------------------------------------+ | fad04b7a-75b5-4f96-aed9-b40654b56e03 | corp-vm-01 | ACTIVE | - | Running | database-servers=fdf8:f53b:82e4::52 | +--------------------------------------+------------+--------+------------+-------------+-------------------------------------+