Configuring IPv6 in UniFi
UniFi supports a wide array of IPv6 deployment methods, including IPoE, Prefix Delegation (PD), SLAAC, MAP-E, DS-Lite, and NAT66. This allows compatibility with modern IPv6-based ISPs such as OCN Virtual Connect, v6 Plus, and many others.
IPv6 WAN Configurations
UniFi gateways make it easy to enable IPv6 with built-in support for common ISP configurations. If you’re unsure which method to use, check with your ISP to ensure compatibility and proper address assignment.
All configurations can be made directly in Settings > Internet > Select WAN > IPv6 Configuration.
Stateless Address Auto-Configuration (SLAAC)
When using SLAAC (Stateless Address Auto-configuration), the UniFi Gateway requests both an IPv6 address and a prefix from your ISP. The received prefix can be used in one of two ways:
- Prefix Delegation: The prefix is automatically split into individual /64 subnets and assigned across each of your VLANs.
- Single Network: The ISP provides a single /64 prefix via Neighbor Discovery Protocol (NDP), typically used for a single VLAN.
As an example, let's assume your ISP provides a /56 prefix; here is how UniFi can assign a unique /64 to two different VLANs:
- VLAN 10: 2001:db8:1234:10::/64
- VLAN20: 2001:db8:1234:20::/64
DHCPv6
DHCPv6 requests both an IPv6 address and a delegated prefix from the ISP. The gateway automatically assigns the received prefix to one or more VLANs, enabling automatic IPv6 subnet distribution across your network.
There are two additional configurations that should be used only if required by your ISP:
- DHCPv6 Client Options: Adds specific client options (1, 11, and 15-17) to DHCPv6 requrests.
- DHCPv6 CoS (Class of Service): Sets a priority value for DHCPv6 packets, often used by ISPs to classify upstream traffic.
Static
Configure a static IP if your ISP provides a fixed IPv6 address and prefix. You will need to manually configure the IPv6 address, gateway, and prefix.
IPv4-Over-IPv6
Some ISPs deliver IPv4 service tunneled over IPv6, especially in regions where IPv4 addresses are limited or expensive. This approach is most common in countries like Japan, Germany, South Korea, and parts of Southeast Asia. In these configurations, VLANs do not require IPv6 addressing since client devices still use IPv4. However, the UniFi Gateway must first establish an IPv6 WAN connection using SLAAC, DHCPv6, or Static IP. This option can be found in Settings > Internet > IPv6 Configuration.
DS-Lite
DS-Lite (Dual-Stack Lite) encapsulates IPv4 traffic within IPv6, allowing ISPs to deliver IPv4 service over an IPv6-only connection. While ISPs automatically provide the required IPv6 gateway address, others may require this to be manually specified. To do so, check or uncheck the Auto toggle under Gateway Address.
DS-Lite Over PPPoE
DS-Lite over PPPoE is most commonly used by ISPs in countries like Germany and South Korea. It functions the same as standard DS-Lite by encapsulating IPv4 traffic within IPv6, but requires a Username and Password to establish a connection over PPPoE.
MAP-E
MAP-E (Mapping of Address and Port with Encapsulation) is supported by UniFi through two Japan-based implementations: v6 Plus (JPIX) and OCN Virtual Connect (NTT Docomo Business). These services allow IPv4 connectivity over an IPv6-only network. The only configuration required is to specify one of the two options above as the Services.
IPv6 Local (LAN) Configuration
Before configuring IPv6 on your VLANs, ensure the WAN is set up with an IPv6 connection method—either SLAAC, DHCPv6, or Static IP. Once the WAN is active, VLANs can be configured to provide IPv6 to clients using one of the following methods.
Interface Type
This determines which IPv6 type will be used on the interface, and corresponds to the IPv6 method configured on your WAN interface.
- Prefix Delegation: Automatically assigns a unique /64 subnet to each VLAN using the prefix received from the ISP. This is available for WANs configured with either SLAAC or DHCPv6.
- Static: Assigns a fixed IPv6 address and subnet to the VLAN interface. This method is only available for those with a static IPv6 WAN configuration provided by the ISP. Use this option if you need to configure Unique Local Addresses (ULA) as your primary IP address, then you can use NAT66 to translate it.
Advanced
Auto is recommended for most setups, however there are additional configurations available:
- Additional IPs: Allows you to specify other IP addresses on the VLAN interface, in addition to the Gateway IP already configured. This can be used to configure Unique Local Addresses (ULA) as your secondary IP address so clients can use multiple IPs simultaneously.
- Client Address Assignment: Determines how clients receive IPv6 addresses, either via SLAAC or DHCPv6. SLAAC is generally recommended since many clients, including Android devices, do not support DHCPv6. If DHCPv6 is ever required, you can also enable Allow SLAAC to maintain compatibility.
- Router Advertisement (RA): Used to inform clients that an IPv6 router is present on the network so that clients can automatically configure their own IPv6 address using SLAAC, discover the default gateway, and optionally receive DNS server information.
- RA Priority: Sets the preferred default gateway for IPv6 clients when multiple routers are available. Clients prioritize routers with higher RA priority (High > Medium > Low) when selecting their default route. Use this to influence gateway selection in multi-router environments.
NAT66
NAT66 enables IPv6-to-IPv6 address translation, typically used to map internal IPv6 addresses (such as Unique Local Addresses [ULA], fc00::/8) to external IPv6 addresses. You can use NAT66 with either ULA or Global Unicast Addresses, depending on your network design.
To configure NAT66:
- Assign a Unique Local Address (ULA) as a primary IP (see Static Interface Type above) or secondary IP (see Additional IPs above) to local clients.
- Navigate to Settings > Policy Table > Create New Policy > NAT.
- Specify IPv6 as your IP Version.
- Configure your NAT rule, following the instructions here.