pre_sanity.yml

---
- hosts: all
  become: yes
  become_method: sudo
  tags:
  - pre_sanity
  - master
  - node
  tasks:

  - name: check 127.0.1.1 /etc/hosts
    # For a system with a permanent IP address, that permanent IP address should be used here instead of 127.0.1.1
    # https://www.debian.org/doc/manuals/debian-reference/ch05.en.html#_the_hostname_resolution
    # This is a good rule, while not mandatory. If you want, you can skip this task with --skip-tags check_etc_hosts
    command: grep '^\s*127.0.1.1' /etc/hosts
    register: command_result
    failed_when: command_result.stdout != ""
    tags:
    - check_etc_hosts
    changed_when: false

  - name: check docker is running
    command: 'docker info'
    tags:
    - check_docker
    when: docker_setup is defined and docker_setup=false
    changed_when: false

  - name: check docker hello world
    shell: docker run --rm -i hello-world | awk '/Hello/ {print $1}'
    register: command_result
    failed_when: command_result.stdout != "Hello"
    tags:
    - check_docker
    when: docker_setup is defined and docker_setup=false
    changed_when: false

# Ideally, to ensure there is no x509 certificate error like:
#' docker pull gcr.io/google_containers/kube-apiserver-amd64:v1.7.2
#Trying to pull repository gcr.io/google_containers/kube-apiserver-amd64 ...
#Get https://gcr.io/v1/_ping: x509: certificate signed by unknown authority '
# yum check-update ca-certificates; (($?==100)) && yum update ca-certificates || yum reinstall ca-certificates
# update-ca-trust extract

# Check ports: https://kubernetes.io/docs/setup/independent/install-kubeadm/