Skip to content

Running k0s worker nodes in Windows#

Experimental status#

Windows support feature is under active development and MUST BE considered as experemential.

Requirements#

The cluster must have at least one worker node and control plane running on Linux. Windows can be used for running additional worker nodes.

Build#

make clean k0s.exe

This should create k0s.exe with staged kubelet.exe and kube-proxy.exe

Description#

the k0s.exe supervises kubelet.exe and kube-proxy.exe During the first run calico install script created as C:\bootstrap.ps1

The bootstrap script downloads the calico binaries, builds pause container and set ups vSwitch settings.

Running#

It is expected to have docker EE installed on the windows node (we need it during the initial calico set up)

C:\>k0s.exe worker --cri-socket=docker:tcp://127.0.0.1:2375 --cidr-range=<cidr_range> --cluster-dns=<clusterdns> --api-server=<k0s api> <token>

Cluster control plane must be inited with proper config (see section below)

Configuration#

Strict-affinity#

To run windows node we need to have strict affinity enabled.

There is a configuration field spec.network.calico.withWindowsNodes, equals false by default. If set to the true, the additional calico related manifest /var/lib/k0s/manifests/calico/calico-IPAMConfig-ipamconfig.yaml would be created with the following values

---
apiVersion: crd.projectcalico.org/v1
kind: IPAMConfig
metadata:
  name: default
spec:
  strictAffinity: true
Another way is to use calicoctl manually: 
calicoctl ipam configure --strictaffinity=true

Network connectivity in AWS#

The network interface attached to your EC2 instance MUST have disabled “Change Source/Dest. Check” option. In AWS console option can be found on the Actions menu for a selected network interface.

Hacks#

We need to figure out proper way to pass cluster settings from controller plane to worker.

While we don't have it, there are CLI arguments: - cidr-range - cluster-dns - api-server

Some useful commands#

Run pod with cmd.exe shell 

kubectl run win --image=hello-world:nanoserver --command=true -i --attach=true -- cmd.exe

Manifest for pod with IIS web-server 

apiVersion: v1
kind: Pod
metadata:
  name: iis
spec:
  containers:
  - name: iis
    image: mcr.microsoft.com/windows/servercore/iis
    imagePullPolicy: IfNotPresent