Configure Secret Resources for Sensitive Values

 

What is a Secret?

A Secret is a Kubernetes object which is used to store and manage sensitive data in Kubernetes such as:

Passwords

API Keys

Database Credentials

Tokens

Certificates

Why Use Secrets?

Not Recommended:-

env:

- name: DB_PASSWORD

  value: "admin123"

Anyone can see the password in the YAML file.

Recommended:- Store the password in a Kubernetes Secret and use it in the Deployment.

Step 1: Create a Secret

kubectl create secret generic mysql-secret --from-literal=username=admin --from-literal=password=admin123

kubectl get secrets

Step 2: Use Secret in Deployment

apiVersion: apps/v1

kind: Deployment

metadata:

  name: nginx-secret-demo

spec:

  replicas: 2

  selector:

    matchLabels:

      app: nginx-secret-demo

  template:

    metadata:

      labels:

        app: nginx-secret-demo

    spec:

      containers:

      - name: nginx

        image: nginx:latest

        env:

        - name: DB_USER

          valueFrom:

            secretKeyRef:

              name: mysql-secret

              key: username

        - name: DB_PASSWORD

          valueFrom:

            secretKeyRef:

              name: mysql-secret

              key: password

kubectl apply -f deployment.yaml

Step 3: Verify Inside the Container

kubectl get pods

kubectl exec -it <pod-name> -- bash

printenv DB_USER

Real-Life Example

Suppose your application connects to MySQL:

Database Host      = mysql-service

Database User      = admin

Database Password  = admin123

Store the password in a Secret instead of hardcoding it in the Deployment YAML, This keeps sensitive data separate from application configuration.