KOR - Kubernetes Orphaned Resources Tool Overview

In this blog post, We will explore a new tool called "KOR" (Kubernetes Orphaned Resources), which assists in identifying unused resources within a Kubernetes(K8S) cluster. This tool will be beneficial for those who are managing Kubernetes clusters.

Requirements:

1.One machine(Linux/Windows/Mac)

2.K8s cluster

Step 1 : Install kor in the machine.

Am using linux VM to do the experiment and for other flavours download the binaries from below link,

https://github.com/yonahd/kor/releases

Download the linux binary for linux VM,

wget https://github.com/yonahd/kor/releases/download/v0.1.8/kor_Linux_x86_64.tar.gz

tar -xvzf kor_Linux_x86_64.tar.gz

chmod 777 kor

cp -r kor /usr/bin

kor --help

Step 2 : Nginx Webserver deployment in K8s

I have a k8s cluster, We will deploy nginx webserver in K8s and try out "kor" tool

Create a namespace as "nginxweb"

kubectl create namespace nginxweb

Using helm, we will deploy nginx webserver by below command,

helm install nginx bitnami/nginx --namespace nginxweb 

kubectl get all -n nginxweb

Step 3 : Validate with kor tool

lets check the unused resources with kor tool in the nginx namespace,

Below command will list all the unused resources available in the given namespace,

Syntax : kor all -n namespace

kor all -n nginxweb

lets delete one service from the nginxweb namespace and try it.

kubectl delete deployments nginx -n nginxweb

Now check what are the resources are available in the namespace,

kubectl get all -n nginxweb

it gives the result of one k8s service is available under the nginxweb namespace

And now try out with kor tool using below command,

kor all -n nginxweb

it gives the same result, that the nginx service is not used anywhere in the namespace.

We can check only configmap/secret/services/serviceaccount/deployments/statefulsets/role/hpa by,

kor services -n nginxweb

kor serviceaccount -n nginxweb

kor secret -n nginxweb

That's all. We have installed the KOR tool and validated it by deleting one of the component in the Nginx web server deployment.

References:

https://github.com/yonahd/kor