IPv4/IPv6 Dual-stack
Kubernetes supports IPv4-only, IPv6-only, and dual-stack networking configurations. For more details, refer to the official Kubernetes documentation.
Installing Rancher on IPv6-Only or Dual-Stack Clusters
Rancher can run on clusters using:
- IPv4-only
- IPv6-only
- Dual-stack (IPv4 + IPv6)
When you install Rancher on an IPv6-only cluster, it can communicate externally only over IPv6. This means it can provision:
- IPv6-only clusters
- Dual-stack clusters
(IPv4-only downstream clusters are not possible in this case)
When you install Rancher on a dual-stack cluster, it can communicate over both IPv4 and IPv6, and can therefore provision:
- IPv4-only clusters
- IPv6-only clusters
- Dual-stack clusters
For installation steps, see the guide: Installing and Upgrading Rancher.
Requirement for the Rancher Server URL
When provisioning IPv6-only downstream clusters, the Rancher Server URL must be reachable over IPv6 because downstream nodes connect back to the Rancher server using IPv6.
Provisioning IPv6-Only or Dual-Stack Clusters
You can provision RKE2 and K3s Node driver (machine pools) or Custom cluster (existing hosts) clusters using IPv4-only, IPv6-only, or dual-stack networking.
Network Configuration
To enable IPv6-only or dual-stack networking, you must configure:
- Cluster CIDR
- Service CIDR
- Stack Preference
Configuration references:
Support for Windows
Kubernetes on Windows:
| Feature | Support Status |
|---|---|
| IPv6-only clusters | Not supported |
| Dual-stack clusters | Supported |
| Services | Limited to a single IP family |
For more information, see the Kubernetes Documentation.
K3s does not support Windows (FAQ)
RKE2 supports Windows, but requires using either Calico or Flannel as the CNI.
Note that Windows installations of RKE2 do not support dual-stack clusters using BGP.
For more details, see RKE2 Network Options.
Provisioning Node Driver Clusters
Rancher currently supports assigning IPv6 addresses in node driver clusters with:
Support for additional providers will be introduced in future releases.
Creating an IPv6-only cluster using the DigitalOcean node driver is currently not supported. For more details, please see rancher/rancher#52523.
Infrastructure Requirements
Cluster nodes must meet the requirements listed in the Node Requirements for Rancher Managed Clusters.
Machine pool configuration guides:
Provisioning Custom Clusters
To provision on your own nodes, follow the instructions in Provision Kubernetes on Existing Nodes.
- Node Public IP and Node Private IP fields accept IPv4, IPv6, or both (comma-separated).
Example:
10.0.0.5,2001:db8::1 - In IPv6-only and dual-stack clusters, specify the node’s IPv6 address as the Private IP.
Infrastructure Requirements
Infrastructure requirements are the same as above for node-driver clusters.
Other Limitations
GitHub.com
GitHub.com does not support IPv6. As a result:
- Any application repositories (
ClusterRepo.catalog.cattle.io/v1CR) hosted on GitHub.com will not be reachable from IPv6-only clusters. - Similarly, any non-builtin node drivers hosted on GitHub.com will also not be accessible in IPv6-only environments.