msjadhav03/kubernetes-prep

Kubernetes

Content

1. Understanding Containers
2. Kubernetes Basics
3. Services and Networking
4. Storage in Kubernetes
5. Configuration Management
6. Helm
7. Application Observability
8. Advanced Kubernetes Concepts
9. Kubernetes Security
10. Multi-Cluster and Federation
11. CI/CD with Kubernetes
12. Kubernetes in the Cloud
13. Troubleshooting
14. Best Practices
15. Kubernetes Community and Resources
16. Hands-On Projects

Understanding Containers

Kubernetes Basics

• Open Source Plateform for managing containerized workloads.

• Kubernetes originates from Greek, meaning helmsman or pilot.

• Containers are a good way to bundle and run your applications

• Kubernetes provides you with a framework to run distributed systems resiliently. It takes care of scaling and failover for your application, provides deployment patterns, and more.

• It provides some generally applicable features common to PaaS offerings, such as deployment, scaling, load balancing, and lets users integrate their logging, monitoring, and alerting solutions.

• It eliminates the need for orchestration.

• Kubernetes comprises a set of independent, composable control processes that continuously drive the current state towards the provided desired state.

• Features

  1. Service discovery and load balancing - if traffic high kubenetes is able to load balance
  2. Storage orchestration - Allows mounting of storage system of choice
  3. Automated rollouts and rollbacks - Can automate kubernetes to create new container
  4. Self healing - Kubernetes restarts containers that fail.
  5. Secrete and configuration mangement - lets you store and manage sensitive information
  6. Horizontal Scaling - Scale your application up or down with simple command or UI

• Kubernetes Components

  • Node

    • Kubernetes cluster consist of set of nodes. Nodes are set of worker machines.
    • Components
      1. kublet - agent that runs on each node in the cluster. Make sures containers are runnning in Pod.
      2. kube-proxy - a network proxy that runs on each node in your cluster.
      3. container runtime - It is responsible for managing the execution and lifecycle of containers within the Kubernetes environment.
      4. addons - Addons use Kubernetes resources (DaemonSet, Deployment, etc) to implement cluster features.
      5. DNS - Cluster DNS is a DNS server.
      6. Web UI Dashboard - web-based UI for Kubernetes clusters.
      7. Container Resource Monitoring - records generic time-series metrics
      8. Cluster-level Logging - is responsible for saving container logs to a central log store with search/browsing interface.
      9. Network Pluggins - are responsible for allocating IP addresses to pods and enabling them to communicate with each other within the cluster.

  • Pod

    • Component of the application workload.

  • Control Plane

    • manages the worker nodes and the Pods in the cluster
    • Control plane's components make global decisions about the cluster.
    • Control plane components can be run on any machine in the cluster.
    • Components
      1. kubi-apiserver - exposes Kubernetes API
      2. etcd - Key value store for storing cluster data
      3. kubi-scheduler - watches newly created pod which has no assigned node and selects them node.
      4. kube-controller-manager - runs controller process - like node controller, Service controller, Job controller, EndpointSlice controller
      5. cloud-controller-manager - lets you link your cluster into your cloud provider's API

• Install : Kubernetes Install

  1. Ubuntu Install
  2. MacOS Install
  3. Windows Install

• Minikube : Install Minikube

  1. Minicube Install

• Namespace : Creating NameSpace

---
apiVersion: v1
kind: Namespace
metadata:
  name: development

• Deployments : Creating Deployment

Basic structure

---
apiVersion: 
kind: 
metadata: 
  name: 
  namespace: 
  labels: 
    app: 
spec: 
  replicas:
  selector:
  template:
    metadata:
    spec:
      containers:
      - name:
        image:
        ports:
        - containerPort: 
        env:
        - name:
        valueFrom:
          fieldRef:
            fieldPath:

• Example

---
apiVersion: apps/v1
kind: Deployment
metadata: 
  name: pod-info-deployment
  namespace: development
  labels:
    app: pod-info
spec:
  replicas: 2
  selector:
    matchLabels:
      app: pod-info
  template:
    metadata:
      labels:
        app: pod-info
    spec:
      containers: 
      - name: pod-info-container
        image: kimschles/pod-info-app:latest
        ports:
        - containerPort: 3000

• Kubernetes Commands

• General

# Get Cluster Info
$ kubectl clutser-info

# Get Nodes List
$ kubectl get nodes

# Get Namespace List
$ kubectl get namespace

• Creation

# Create Resource
$ kubectl apply -f yaml_file_name.yaml

# Create Resource from link
kubectl apply -f https://git.io/vPieo 

# Create Multiple resource
kubectl apply -f ./my1.yaml -f ./my2.yaml   

• Listing

# Get Pods List within specific pod
$ kubectl get pods -n namespace_name

# List Out Service
$ kubectl get services 

# Get pods from all namspaces
$ kubectl get pods --all-namspaces

# List out deployment
$ kubectl get deployments deployement_name

# Get pods YAML
$ kubectl get pod pod_name -o yaml

• Deletion

# Deleting with YAML or json
$ kubectl delete -f ./pod.json   

Services and Networking

Kubernetes Services: Learn how to expose your applications to the network and how to configure different types of services (e.g., ClusterIP, NodePort, LoadBalancer).

Ingress Controllers: Understand how to manage and route external traffic to your services using Ingress controllers.

Network Policies: Explore network policies to control and secure communication between pods.

Storage in Kubernetes

Persistent Volumes (PVs) and Persistent Volume Claims (PVCs): Learn how to manage storage in Kubernetes, including volume provisioning and mounting.

Configuration Management

ConfigMaps and Secrets: Discover how to manage configuration data and sensitive information securely.

Helm

Helm Package Manager: Learn how to use Helm for packaging and deploying applications to Kubernetes.

Application Observability

Logging and Monitoring: Explore tools like Prometheus and Grafana for monitoring and logging in Kubernetes clusters.

Advanced Kubernetes Concepts

StatefulSets: Understand how to manage stateful applications in Kubernetes.

Custom Resource Definitions (CRDs): Learn how to define custom resources to extend Kubernetes functionality.

Operators: Explore Kubernetes operators for automating complex, application-specific tasks.

Kubernetes Security

RBAC (Role-Based Access Control): Learn how to set up fine-grained access control in Kubernetes.

Pod Security Policies: Understand how to implement security policies for pods.

Multi-Cluster and Federation

Multi-Cluster Management: Learn how to manage multiple Kubernetes clusters.

CI/CD with Kubernetes

CI/CD Pipelines: Integrate Kubernetes into your CI/CD pipelines using tools like Jenkins, GitLab CI/CD, or ArgoCD.

Kubernetes in the Cloud

Managed Kubernetes Services: Explore managed Kubernetes offerings from cloud providers like AWS EKS, Google GKE, and Azure AKS.

Troubleshooting

Debugging and Troubleshooting: Develop skills for diagnosing and resolving issues in Kubernetes clusters.

Best Practices

Kubernetes Best Practices: Learn best practices for optimizing performance, security, and scalability in Kubernetes.

Kubernetes Community and Resources

Kubernetes Documentation: Continuously refer to the official Kubernetes documentation for in-depth information.

Kubernetes Community: Engage with the Kubernetes community through forums, mailing lists, and social media.

Kubernetes Conferences and Meetups: Attend Kubernetes-related events and conferences to network and stay updated on the latest trends.

Online Courses and Tutorials: Explore online courses and tutorials on platforms like Udemy, Coursera, and edX.

Books: Consider reading books dedicated to Kubernetes, such as "Kubernetes Up & Running" and "The Kubernetes Book."

Hands-On Projects