node-label-controller

README

node-label-controller

This controller watches the Kubernetes nodes and attaches a label to the Kubernetes Node object when the node uses a specific operating system based on a command line argument that should decide which operating system is targeted to be labeled.

On Local Environment

Setup a kind cluster

build the binary

go build

Execute the binary

./node-label-controller "linux"

On Kind Cluster

Build the controller image and push to docker registry

docker build -t akankshakumari393/node-label-controller:0.0.1 .
docker push akankshakumari393/node-label-controller:0.0.1

create a namespace in which controller would run

kubectl create namespace controller

Create ClusterRole to give permission for nodes

kubectl create clusterrole cluster-role --verb=list,watch,update --resource=nodes
# kubectl create -f k8s-resources/clusterrole.yaml

Create ClusterRoleBindings give access to default Service account in controller namespace

kubectl create clusterrolebinding cluster-role-binding --clusterrole=cluster-role --user=system:serviceaccount:controller:default
# kubectl create -f k8s-resources/clusterrolebinding.yaml

Create node label os controller as deployment

kubectl create -f k8s-resources/deployment.yaml -n controller

This would update the Node resource and add label k8c.io/uses-linux=true in above example if the OS matches the arg provided in the deployment, in our case linux