Deployments¶

Description¶

A Deployment manages a set of identical pods and ensures that the desired number of replicas are running.

Deployments provide features such as:

rolling updates
scaling
rollback to previous versions

Deployments are commonly used to run stateless applications.

Key Fields¶

Field	Description
`spec.replicas`	Number of desired pods
`spec.selector`	Labels used to identify pods
`spec.template`	Pod template used to create pods
`spec.strategy`	Update strategy

Example Deployment¶

apiVersion: apps/v1
kind: Deployment
metadata:
  name: web-app
spec:
  replicas: 3
  selector:
    matchLabels:
      app: web
  template:
    metadata:
      labels:
        app: web
    spec:
      containers:
      - name: nginx
        image: nginx

Common Commands¶

Create a deployment:

kubectl apply -f deployment.yaml

Scale deployment:

kubectl scale deployment web-app --replicas=5

Check deployment status:

kubectl get deployments

Use Cases¶

Deployments are commonly used for:

web applications
API services
stateless workloads

Pods
Services
Horizontal Pod Autoscaler