Oracle Cloud Infrastructure Documentation

Enabling IPv6 Virtual Networking

Compute instances on Private Cloud Appliance can be configured for connectivity with the on-premises network using IPv6 addresses. This is a dual-stack implementation, meaning IPv6 is supported as an optional addition in parallel with IPv4.

Important

IPv6 virtual network connectivity is currently only supported for compute instances with SR-IOV (single root I/O virtualization) VNICs. See Configuring SR-IOV for Virtual Networking.

Prerequisites

The system must meet these prerequisites before you can enable IPv6 connectivity on compute instances.

  • The option to enable IPv6 traffic is introduced in software version 3.0.2-b1483396 (September 2025). If the active controller software is older, the appliance must be upgraded first.

  • The appliance Network Environment must be reconfigured to route ingress and egress traffic between the system and the on-premises network. Configuration changes on the uplinks from the spine switches are required.

  • The VCN and related networking resources must be configured to route traffic to and from compute instances with IPv6 VNICs. Instructions are provided further in this topic.

Configuring IPv6 on Virtual Network Resources

IPv6 addresses can optionally be added to both new and existing compute instances and network resources.

Note

All IPv6 addresses are globally unique. Therefore, NAT is not used, and there is no concept of public and private IPs.

In an SR-IOV VCN, the default route table allows all IPv4 and IPv6 traffic, and the default security list allows all egress and ingress traffic. The respective route rules and security rules cannot be updated or deleted.

  1. Enable IPv6 for the VCN. Only one CIDR (IPv4 plus IPv6) is allowed. Bring Your Own IP address space isn't supported. The address range must be at least /64 with a maximum of /7.

    1. To create a new VCN, follow the instructions in Creating a VCN. In addition, enable IPv6 by selecting Enable IPv6 Protocol. Enter the IPv6 Prefix for this VCN.

    2. To enable IPv6 for an existing VCN, navigate to the VCN detail page.

      In the top-right corner, select Controls, then select Add IPv6 CIDR. In the dialog box, enter the IPv6 Prefix for this VCN and confirm.

    The VCN now has both an IPv4 and IPv6 address range.

  2. Enable IPv6 for the subnets that require it.

    1. To create a new subnet, follow the instructions in Creating a Subnet. In addition, enable IPv6 by selecting the VCN's IPv6 Prefix and entering a valid IPv6 CIDR Block for this subnet.

    2. To enable IPv6 for an existing subnet, navigate to the subnet detail page. In the top-right corner, select Controls, then select Add IPv6 CIDR. In the dialog box, select the VCN's IPv6 Prefix, enter a valid IPv6 CIDR Block for this subnet, and select the Add button confirm.

    The subnet CIDR is always a /64 within the VCN address range. The first and last 4 addresses are reserved and cannot be assigned to compute instances.

  3. If you plan to use a Dynamic Routing Gateway (DRG) with a new IPv6 enabled VCN, remember to create the SR-IOV compatible DRG and attach the VCN to it. See Connecting to the On-Premises Network through a Dynamic Routing Gateway (DRG).

    If you are enabling IPv6 for an existing VCN that is already attached to a DRG, no additional configuration steps are required. The DRG supports both IPv4 and IPv6 traffic when it's enabled for the VCN.

    Ensure that route rules exist for both IPv4 and IPv6 traffic.

  4. Assign IPv6 addresses to your compute instances.

    Compute instances are first created with a primary IPv4 address. An optional IPv6 addresses is assigned when creating and attaching a secondary VNIC to an SR-IOV subnet.

    1. Navigate to the compute instance detail page. Under Resources, select Attached VNICs.

    2. Select Create VNIC Attachment. Enter a name and select the VCN and subnet to attach the VNIC to.

    3. Under IPv6, select Assign IPv6 Address. Select the available IPv6 Prefix and select either automatic (default) or manual address assignment.

    4. Click Create Attachment to assign an address from the subnet IPv6 range to this VNIC. The compute instance is now attached to the subnet through this VNIC.

  5. Configure the VNICs inside the compute instances.

    SR-IOV VNICs are set up in pairs and must form a bond port. Run the configure_vfio.py script provided in the Oracle Systems blog Automating SR-IOV/VFIO bond creation on Oracle Compute Cloud@Customer and Private Cloud Appliance. The script configures the bond interface (vfio0) and assigns the correct IPv4 and IPv6 addresses.