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Ansible

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Run playbook without inventory file
#

ansible-playbook --connection=local --inventory xxx.xxx.xxx.xxx, playbook.yml # be aware of the comma
ansible all -i localhost, -m setup -c local

Output shell command
#

- name: debug
  shell: ls -al /var/www/
  register: out

- name: out
  debug:
    var: out.stdout_lines

Get a list of facts
#

ansible -m setup localhost | sed '1c {' | jq '.ansible_facts | keys'
# alternatively | python -mjson.tool

Ansible playbook waiting for reboot of target
#

UPDATE: Since Ansible 2.7 there is a reboot module

Sometimes a reboot of a machine during Ansible operation is required. Reboot results in a lost ssh connection.

Here is a way how to properly tell Ansible to handle a machines reboot in the middle of its operation without failing.

The following playbook snippet reconfigures the network (especially the IP), performs a reboot of the server while waiting for it to come back with its new IP address. host_name and ip_address must be provided from a external call.

---
- name: Configure interface
  template:
    src: etc/interfaces.j2
    dest: /etc/network/interfaces
    owner: root
    group: root
    mode: "u=rw,g=r,o=r"

- name: Set hostname
  hostname:
    name: "{{ host_name }}"
  tags: [hostname]

- name: Reboot Machine
  shell: sleep 2 && shutdown -r now "Ansible reboot"
  async: 1
  poll: 0
  ignore_errors: true

- name: Wait for the remote network interface to come back up
  local_action:
    module: wait_for
    host: "{{ ip_address }}"
    port: 22
    delay: 30
    timeout: 300
    state: started
  become: false
  register: wait_result

- name: Change ansible_ssh_host to new ip for further connections
  set_fact:
    ansible_ssh_host: "{{ ip_address }}"

- name: Interface configuration finished
  debug:
    msg: "Interface configuration finished"
  when: wait_result|succeeded

Ansible role testing with Docker and Molecule
#

Requirements
#

  1. Ansible
  2. Docker
  3. pip install molecule, docker-py, testinfra

Big Picture
#

graph LR A[Ansible Role] --> B((Molecule)) click A "https://www.ansible.com/" "Ansible Homepage" click B "https://github.com/metacloud/molecule" "Molecule Homepage" B --> C[Docker Container] click B "https://www.docker.com/" "Docker Homepage" B --> D[Play Playbook] B --> E[Testinfra] click B "https://github.com/philpep/testinfra" "Testinfra Homepage" B --> F[Clean up]

molecule.yml
#

---
dependency:
  name: galaxy
driver:
  name: docker
lint:
  name: yamllint
platforms:
  - name: foo
    image: centos/systemd
    volumes:
      - /sys/fs/cgroup:/sys/fs/cgroup:ro
    privileged: true
    override_command: false
    exposed_ports:
      - 80/udp
      - 80/tcp
    published_ports:
      - 0.0.0.0:8080:80/udp
      - 0.0.0.0:8080:80/tcp
    networks:
      - name: foo
    pre_build_image: false
  - name: foo-db
    image: mysql:5.7
    override_command: false
    env:
      MYSQL_ROOT_PASSWORD: admin
      MYSQL_DATABASE: admin
      MYSQL_USER: admin
      MYSQL_PASSWORD: admin
    exposed_ports:
      - 3306/udp
      - 3306/tcp
    networks:
      - name: foo
    pull: true
    pre_build_image: true
scenario:
  name: default
  test_sequence:
    - lint
    - destroy
    - dependency
    - syntax
    - create
    - prepare
    - converge
    - idempotence
    - side_effect
    - verify
    - destroy
provisioner:
  name: ansible
  lint:
    name: ansible-lint
verifier:
  name: testinfra
  lint:
    name: flake8