How to properly set up Environment="KUBELET_EXTRA_ARGS=--cloud-provider=external" in K3S

[wanGiB]

I have the following set up for the control planes:

The first etcd server:

curl -sfL https://get.k3s.io | INSTALL_K3S_EXEC="--kubelet-arg=cloud-provider=external --node-name=$(hostname -f) --disable=traefik --disable=servicelb --disable-cloud-controller --prefer-bundled-bin --cluster-init --node-ip=$INTERNAL_IP --tls-san $PUBLIC_IP" sh -s - server

And the following when joining additional servers

curl -sfL https://get.k3s.io | INSTALL_K3S_EXEC="--kubelet-arg=cloud-provider=external --node-name=$(hostname -f) --disable=traefik --disable=servicelb --disable-cloud-controller --prefer-bundled-bin --node-ip=$INTERNAL_IP --server https://$FIRST_SERVER_IP:6443 --tls-san $PUBLIC_IP" K3S_TOKEN=$FIRST_SERVER_JOIN_SECRET sh -s - server

And here is the equivalent script when joining worker nodes to the cluster:

export K3S_NODE_NAME=$(hostname -f)
export K3S_KUBELET_EXTRA_ARGS="--cloud-provider=external"
curl -sfL https://get.k3s.io | K3S_TOKEN=$FIRST_SERVER_JOIN_SECRET sh -s - agent --server https://$FIRST_SERVER_IP:6443

I just want to be sure if this way of setting the cloud provider external flag is correct in k3s?

[lukasmetzner]

Hi,

Here you can find the official K3s documentation on this topic. Just as a note, while our cloud controller manager works with K3s, we don’t directly support K3s itself, as this question seems more specific to K3s than to our product.

In general, this looks good to me. As described in the kubelet cli reference, the value should be set to external, if you are running a external cloud controller manager, like ours.

Did you experience any issues while testing?

Best Regards

Lukas

[hegerdes]

You should be fine by setting --k3s-extra-args="--kubelet-arg=cloud-provider=external"

I would not worry to much about the unofficial support from hetzner for k3s. They are also using k3s for integration tests. See here how they use terraform to setup a k3s cluster:

https://github.com/hetznercloud/kubernetes-dev-env/blob/40b22edf75a85d603c39939a2d00bf16d86bb365/main-setup.tf#L32-L53