CCM with Hetzner network attempts to create IPv6 routes

[Xinayder]

TL;DR

Setting up a dual stack k8s cluster with HCCM and Hetzner's inter-server networking will result in the CCM attempting to create IPv6 routes for the internal Hetzner network.

Expected behavior

IPv6 routes should be created normally.

Observed behavior

The cloud controller keeps trying to create an IPv6 route on a v4 only network, failing with the error: Could not create route <route-id> 2001:cafe:42::/64 for node <node_name>: hcloud/CreateRoute invalid input in field 'destination' (invalid_input)

Minimal working example

Setup k3s with:

disable-cloud-controller: true
disable-network-policy: true
kubelet-arg: "cloud-provider=external"
cluster-init: true
cluster-cidr: 10.42.0.0/16,2001:cafe:42::/56
service-cidr: 10.43.0.0/16,2001:cafe:43::/112

Setup a Hetzner network with address 10.0.0.0/24

Log output

`Could not create route <route-id> 2001:cafe:42::/64 for node <node_name>: hcloud/CreateRoute invalid input in field 'destination' (invalid_input)`

Additional information

No response