135 lines
3.8 KiB
Plaintext
135 lines
3.8 KiB
Plaintext
---
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title: Kubernetes
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tags:
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- Developer
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- Technical documentation
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- Code
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- Programming
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sidebar_position: 1
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---
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This guide provides step-by-step instructions for setting up a Kubernetes cluster using kind, configuring multiple nodes, and installing the Metrics Server.
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## Prerequisites
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Ensure you have the following installed:
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- [Docker](https://docs.docker.com/get-started/get-docker/) (required for running `kind` clusters).
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- [Kind](https://kind.sigs.k8s.io/docs/user/quick-start/) (Kubernetes in Docker).
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- [Kubectl](https://kubernetes.io/docs/tasks/tools/) (Kubernetes command-line tool).
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Additionally, ensure that Kubernetes tools are enabled in your environment by setting the following variable in your `.env` file:
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```bash
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# Enable Kubernetes tool
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ENABLE_KUBERNETES=true
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```
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### 1. Creating a Kubernetes Cluster with Multiple Nodes
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We will create a Kubernetes cluster using `kind` with one control plane node and two worker nodes.
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#### Define the Cluster Configuration
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Create a configuration file named `kind-config.yaml` with the following content:
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```bash
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cat > kind-config.yaml <<EOF
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# three node (two workers) cluster config
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kind: Cluster
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apiVersion: kind.x-k8s.io/v1alpha4
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nodes:
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- role: control-plane
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kubeadmConfigPatches:
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- |
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kind: KubeletConfiguration
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apiVersion: kubelet.config.k8s.io/v1beta1
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kubeReserved:
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cpu: "250m"
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memory: "256Mi"
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systemReserved:
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cpu: "500m"
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memory: "512Mi"
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evictionHard:
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memory.available: "200Mi"
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- role: worker
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- role: worker
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EOF
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```
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#### Create the Cluster
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Run the following command to create the Kubernetes cluster:
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```bash
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kind create cluster --name k8s-playground --config kind-config.yaml
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```
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This will provision a cluster named `k8s-playground` with the specified node configuration.
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### 2. Installing the Metrics Server
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The Metrics Server is required for gathering resource utilization metrics like CPU and memory usage. It is essential for features such as Horizontal Pod Autoscaling.
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#### Deploy the Metrics Server
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Run the following command to install the Metrics Server:
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```bash
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kubectl apply -f https://github.com/kubernetes-sigs/metrics-server/releases/download/v0.7.2/components.yaml
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```
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#### Disable TLS Verification (For Local Development)
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In local environments, Kubernetes nodes might not have valid certificates. To disable TLS verification, patch the deployment:
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```bash
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kubectl patch -n kube-system deployment metrics-server --type=json \
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-p '[{"op":"add","path":"/spec/template/spec/containers/0/args/-","value":"--kubelet-insecure-tls"}]'
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```
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This allows the Metrics Server to communicate with kubelets that use self-signed certificates.
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### 3. Verifying the Setup
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After completing the setup, verify that the cluster is running correctly:
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#### Check the Cluster Nodes
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```bash
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kubectl get nodes
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```
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Expected output:
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```bash
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NAME STATUS ROLES AGE VERSION
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k8s-playground-control-plane Ready control-plane Xs vX.Y.Z
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k8s-playground-worker Ready worker Xs vX.Y.Z
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k8s-playground-worker2 Ready worker Xs vX.Y.Z
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```
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#### Check Metrics Server Status
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```bash
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kubectl get deployment -n kube-system metrics-server
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```
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Expected output:
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```bash
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NAME READY UP-TO-DATE AVAILABLE AGE
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metrics-server 1/1 1 1 Xs
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```
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#### Get Node Resource Metrics
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```bash
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kubectl top nodes
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```
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This command should return CPU and memory usage statistics for each node.
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## Conclusion
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You have successfully set up a multi-node Kubernetes cluster using kind and installed the Metrics Server for monitoring resource usage. This setup is useful for local development and testing Kubernetes workloads before deploying them to a production environment. |