Lab 8 - Solution¶

Mandatory¶

Replace copy with template¶

Change your ntp role
Create the templates directory in your ntp role /home/ansible/training/roles/ntp/templates
Create the template file templates/ntp.conf.j2 (copy the ntp.conf file from files/ntp.conf)
In your tasks file, replace the copy module with the template module
Add a new task to start and enable the ntp service (see Service Module)
Run the playbook
Verify the configuration file
If everything works, delete the file files/ntp.conf

Hint

Don’t forget the .j2 file extension.

mkdir /home/ansible/training/roles/ntp/templates
cp roles/ntp/files/ntp.conf roles/ntp/templates/ntp.conf.j2

# file: roles/ntp/tasks/main.yml
- name: configure ntp
  template:
    src: ntp.conf.j2
    dest: /etc/ntp.conf
    owner: root
    group: root
    mode: 0644
  tags:
    - configuration

- name: start and enable ntp
  service:
    name: ntp
    state: started
    enabled: yes
  tags:
    - service

# run the playbook
ansible-playbook ntp-role.yml

# remove the old ntp.conf
rm roles/ntp/files/ntp.conf

Use facts and ansible_header¶

Add a comment in the ntp.conf.j2 file with the fact ansible_os_family
Add a ansible_managed header in the ntp.conf.j2 file
Run the playbook and verify the configuration file on the managed host

# file: roles/ntp/templates/ntp.conf.j2
# {{ ansible_managed }}
# {{ ansible_os_family }}
...

# on the control node
ansible-playbook ntp-role.yml

# verify the configuration on the managed host
ssh web1.<firstname>.lab "head /etc/ntp.conf"
# Ansible managed
# Debian

Loop¶

Replace the pool server entries in your template file ntp.conf.j2
Loop over your ntp_servers list in the template ntp.conf.j2
Run the playbook with diff, to see the changes
Verify the configuration file

# file: roles/ntp/templates/ntp.conf.j2
{% for srv in ntp_servers %}
pool {{ srv }} iburst
{% endfor %}

# on the control node
ansible-playbook ntp-role.yml --diff

# on the remote host
ssh web1.<firstname>.lab "cat /etc/ntp.conf"

When Conditionals¶

Make sure the ntp role works on Debian and RedHat
Create the variable file vars/RedHat.yml and add the variable ntp_service with the value ntpd
Create a new task to include the variable file RedHat.yml (see Include_Vars Module) -> Put this task in first place, to ensure it run before all other tasks
Ensure, the include_vars task is running only on the ansible_os_family RedHat (see Chapter Variables)

# file: roles/ntp/vars/RedHat.yml
---
ntp_service: 'ntpd'

# file: roles/ntp/tasks/main.yml
---
- name: include redhat variables
  include_vars: RedHat.yml
  when: ansible_os_family == "RedHat"

Define a role default in defaults/main.yml for the variable ntp_service with the value ntp
Use the new variable ntp_service in your handlers/main.yml and tasks/main.yml

# file: roles/ntp/defaults/main.yml
...
ntp_service: 'ntp'

# file: roles/ntp/tasks/main.yml
- name: start and enable ntp
  service:
    name: '{{ ntp_service }}'
    state: started
    enabled: yes
  tags:
    - service

# file: roles/ntp/handlers/main.yml
- name: restart ntp
  service:
    name: '{{ ntp_service }}'
    state: restarted

Edit your installation task and use the package module instead of the apt module
Edit your playbook to run the ntp role on the web hostgroup
Run the playbook

# file: roles/ntp/tasks/main.yml
- name: install ntp packages
  package:
    name: '{{ item }}'
    state: latest
  with_items:
    - '{{ ntp_packages }}'
  tags:
    - installation

# file: ntp-role.yml
---
- hosts: web

  roles:
    - ntp

# run the playbook
ansible-playbook ntp-role.yml

Overwrite role default with group_vars¶

Create a group_vars file for your db hostgroup
Add the list variable ntp_servers with the items ntp1.lab, ntp2.lab and ntp3.lab
Edit your playbook to run the ntp role all hosts
Run the playbook
Verify your db host has other ntp servers

# file: group_vars/db.yml
---
ntp_servers:
  - ntp1.lab
  - ntp2.lab
  - ntp3.lab

# file: ntp-role.yml
---
- hosts: all

  roles:
    - ntp

# run the playbook
ansible-playbook ntp-role.yml

# on the remote host
ssh db.<firstname>.lab "cat /etc/ntp.conf"

Commit your changes¶

add all files to your git repo and commit it

git status
git add roles/*
git commit -m 'lab 8'