daemonset-example.yaml

apiVersion: apps/v1
kind: DaemonSet
metadata:
  labels:
    name: startup
  name: startup
  namespace: default
spec:
  selector:
    matchLabels:
      name: startup
  template:
    metadata:
      labels:
        name: startup
    spec:
      containers:
      - name: startup
        image: gcr.io/google-containers/startup-script:v1
        imagePullPolicy: IfNotPresent
        securityContext:
          privileged: true
        env:
        - name: STARTUP_SCRIPT
          value: |
            #! /bin/bash
            sysctl -w vm.max_map_count=262144
            # Increase max open pseudo terminals to avoid the following error when using shell to connect on containers:
            #   'starting container process caused "open /dev/ptmx: no space left on device": unknown'
            sysctl -w kernel.pty.max=8192
            echo "done"