ConfigMap as a "Volume"

We can use a ConfigMap to declare a file and then mount it as a volume to any container:

The ConfigMap is specified in the volumes section, the name of the volume has to match the volumeMounts name.

Two things to take into account, the mountPath could have been any path, the subPath must match the ConfigMap→data→key/file(index.html, in this case) defined.

The Service can be used to attach to an existing Ingress or any networking resource.

  volumeMounts:
  - name: html-volume
    mountPath: /usr/share/nginx/html/index.html
    subPath: index.html
  ports:
  - containerPort: 80
volumes:
- name: html-volume
  configMap:
    name: html

apiVersion: v1
kind: ConfigMap
metadata:
  name: html
data:
  index.html: |
    <!doctype html>
    <html lang="en">
    <head>
      <meta charset="utf-8">
      <title>Hello World</title>
    </head>
    <body>
      <h2>Hello</h2>
    </body>
    </html>
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: simple-web-server
spec:
  selector:
    matchLabels:
      app: simple-web-server
  template:
    metadata:
      labels:
        app: simple-web-server

    spec:
      containers:
      - name: simple-web-server
        image: nginx:latest
        resources:
          limits:
            memory: "128Mi"
            cpu: "500m"
        volumeMounts:
        - name: html-volume
          mountPath: /usr/share/nginx/html/index.html
          subPath: index.html
        ports:
        - containerPort: 80
      volumes:
      - name: html-volume
        configMap:
          name: html
---
apiVersion: v1
kind: Service
metadata:
  name: simple-web-server-service
spec:
  type: NodePort
  selector:
    app: simple-web-server
  ports:
  - port: 80
    targetPort: 80
    protocol: TCP

Table of Contents

ConfigMap as a "Volume"