[Support for IPv6]: Steps to add k3d cluster with ipv6 Only

[Imboncy]

Details

• I want to run the k3d cluster with only Ipv6 enable but I could not find any informative docs. Can someone help me on that?

• I have the Calico config that allows only ipv6 but when i launch the cluster it starts with IPv4 y default.

[iwilltry42]

Hi @Imboncy , thanks for opening this issue!
Does the whole cluster (i.e. also the nodes) have to run in ipv6 only mode? (that's the only part that would affect k3d)
Anyway, it's not supported by upstream K3s yet (see k3s-io/k3s#284 & k3s-io/k3s#2123).

[olix0r]

It looks like k3s-io/k3s#284 & k3s-io/k3s#2123 are resolved now.

@iwilltry42 If I understand correctly, it should now be possible to configure k3s to use an IPv6 pod network in k3d?

[iwilltry42]

@olix0r didn't look into it again yet, but it's back on the list.
What about my question above?

Does the whole cluster (i.e. also the nodes) have to run in ipv6 only mode? (that's the only part that would affect k3d)

[olix0r]

Does the whole cluster (i.e. also the nodes) have to run in ipv6 only mode? (that's the only part that would affect k3d).

I don't think this is required for my use case, though it would ultimately be a nice addition at some point.

Basically, we're hearing about more users of IPv6 clusters and want to use k3d as an integration testing environment (for Linkerd). We primarily care about pod-to-pod and pod-to-service communication for these tests.

[zalegrala]

I'm using k3d for a local development environment, and we've got a user who wants to deploy our stuff in an ipv6-only cluster. In order to test locally and ensure functionality, having k3d support an IPv6 only mode would be pretty handy for this use case.

[almereyda]

Implementing this support could start with support for the kubeAPI.hostIP key allowing IPv6 addresses, such as ::1:

$ K3D_FIX_CGROUPV2=true k3d cluster create --config k3d-config.yaml
FATA[0000] Schema Validation failed for config file k3d-config.yaml: - kubeAPI.hostIP: Does not match format 'ipv4'

[alpeb]

Hi @iwilltry42, any updates on this? We're finally adding IPv6 support for linkerd and would love to be able to have this tested via our current k3d-based integration tests suite.