Problem with IP addresses in Clusters with private and public network

[simonostendorf]

Hello,

I am wondering what I am doing wrong when I create a cluster.

Here is the initial scenario:
I want a cluster where the nodes have both private and public IP addresses. The whole thing is currently created via a ClusterClass.

Problem:
The nodes get a private and public address as desired, but the pods partly use the public IP. Can I pin this to the private IP? I can't enter this in the configs because I don't know the IP there and ClusterAPI would then have to replace it.

Thank you for your help!

Edit: I am using advertise-address 10.0.0.2 (API LB) and bind-address 0.0.0.0

The pod (eg. kube-apiserver) shows hostIP: 10.0.0.9, podIP: 128.140.X.X and podIPs: [ip: 128.140.X.X].

I could fix this first error by adding the node private ip together with the hostname into the /etc/hosts. But kubernetes service for api (ip 10.20.0.1 for me) doesn't work because the endpoints use the public ip because kubeadm uses this is the advertise address refering to this post

[batistein]

This needs to be configured in the cni. The cluster-api is not responsible for this.
FYI: the cluster-api only manages the cluster lifecycle, configuration of the cluster needs to be done in the node-image, kubeadm or in the basic applications / cluster-addons (e.g cni, ccm etc.)