> For the complete documentation index, see [llms.txt](https://www.ankitavirani.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.ankitavirani.com/experience/devops-infrastructure.md).

# DevOps/Infrastructure

### 1. Docker 🐳

Docker is a platform for developing, shipping, and running applications in containers.

#### Key Concepts:

* Containers: Lightweight, standalone executable packages
* Images: Read-only templates used to create containers
* Dockerfile: Script to build Docker images
* Docker Hub: Cloud-based registry for Docker images

#### Architecture:

<figure><img src="/files/TFa2XTK8nbUYVbwxf3GV" alt=""><figcaption></figcaption></figure>

#### Example Dockerfile:

```
FROM node:14
WORKDIR /app
COPY package*.json ./
RUN npm install
COPY . .
EXPOSE 3000
CMD ["npm", "start"]
```

### 2. Kubernetes ☸️

Kubernetes is an open-source container orchestration platform for automating deployment, scaling, and management of containerized applications.

#### Key Concepts:

* Pods: Smallest deployable units in Kubernetes
* Nodes: Worker machines in a Kubernetes cluster
* Clusters: Set of nodes that run containerized applications
* Services: Abstract way to expose applications running on pods

#### Architecture:

<figure><img src="/files/AkihcCMdc1pWthHcoCBg" alt=""><figcaption></figcaption></figure>

#### Example Kubernetes Deployment:

```yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  replicas: 3
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.14.2
        ports:
        - containerPort: 80
```

### 3. CI/CD 🔄

Continuous Integration and Continuous Deployment (CI/CD) is a method to frequently deliver apps to customers by introducing automation into the stages of app development.

#### Key Concepts:

* Continuous Integration: Merging code changes frequently
* Continuous Delivery: Automatically preparing code for release
* Continuous Deployment: Automatically releasing to production
* Pipelines: Automated processes for building, testing, and deploying

#### CI/CD Pipeline:

<figure><img src="/files/ooOJYveEd0AXgHtRxppT" alt=""><figcaption></figcaption></figure>

#### Example GitLab CI/CD Configuration:

```yaml
stages:
  - build
  - test
  - deploy

build:
  stage: build
  script:
    - npm install
    - npm run build

test:
  stage: test
  script:
    - npm run test

deploy:
  stage: deploy
  script:
    - npm run deploy
  only:
    - master
```

### 4. Docker Swarm 🐝

Docker Swarm is a native clustering and orchestration solution for Docker.

#### Key Concepts:

* Nodes: Docker hosts participating in the swarm
* Services: Definition of tasks to execute on nodes
* Tasks: Docker containers executing commands
* Load Balancing: Distributing service containers across nodes

#### Architecture:

<figure><img src="/files/ts9cE6mNBlzWBgXAv42y" alt=""><figcaption></figcaption></figure>

#### Example Docker Swarm Service:

```bash
docker service create --name my-web-server \\
                      --replicas 3 \\
                      --publish 80:80 \\
                      nginx
```

The core of modern DevOps and Infrastructure management, enabling efficient development, deployment, and scaling of applications. 🚀