Update K3s

Sometimes we need to update our kubernetes cluster to a newer version. As K3s came as single binary the update is pretty easy as we only need to swap the binary and restart the service.

Drain Node

First we have to disable the node in k3s

kubectl cordon <NODE>
kubectl drain <NODE> --ignore-daemonsets

Check for new version

• Go to https://github.com/k3s-io/k3s/releases
• Check for the newest version with tag “Latest”
• copy link to the Asset for your system

Now export that URL as env variable

export K3SURL=<COPY_LINK_HERE>

Remove old binary

Delete the old version

cd /usr/local/bin
rm k3s

Get new binary

We have to download the new binary and make it executable

wget $K3SURL
chmod 755 k3s

Check

Now the node that was updated should the in a newer version

kubectl get nodes

Release Node as Ready

Now the node will become Ready

kubectl uncordon <NODE>

Remaining Nodes

Do the steps above for all nodes.