Lamp Contd
- As of now our playbook is as shown below
---
- hosts: webservers
become: yes
vars:
package_apache: apache2
packages_php_modules:
- php
- libapache2-mod-php
- php-mysql
- php-cli
tasks:
- name: fail playbook on unsupported platforms
fail:
msg: 'This playbook is currently developed only for ubuntu 18'
when: ansible_distribution != 'Ubuntu'
- name: update and install apache
apt: # https://docs.ansible.com/ansible/latest/modules/apt_module.html
name: "{{ package_apache }}"
update_cache: yes
state: present
- name: restart and enable apache2
service:
name: "{{ package_apache }}"
enabled: yes
state: restarted
- name: install php modules
apt:
name: "{{ item }}"
state: present
loop: "{{ packages_php_modules}}"
- name: restart apache2
service:
name: "{{ package_apache }}"
state: restarted
- In the above playbook the problem is restart service is written multiple times and restart apache should happen only when the apache is installed or php modules are installed
- To solve this Ansible has handlers Refer Here
- To understand handlers lets write a simple playbook
---
- hosts: all
become: yes
tasks:
- name: uninstall git
package:
name: git
state: absent
- name: log message for uninstallation
debug:
msg: "git is uninstalled"
- This playbook displays git is uninstalled message every time, but actually it has to display the message when git is uninstalled by ansible, so using handlers will solve the issue
---
- hosts: all
become: yes
tasks:
- name: uninstall git
package:
name: git
state: absent
notify:
- log message for uninstallation
handlers:
- name: log message for uninstallation
debug:
msg: "git is uninstalled"
- Now in the same approach if we add handlers to handle service restarts our playbook will look like
---
- hosts: webservers
become: yes
vars:
package_apache: apache2
packages_php_modules:
- php
- libapache2-mod-php
- php-mysql
- php-cli
tasks:
- name: fail playbook on unsupported platforms
fail:
msg: 'This playbook is currently developed only for ubuntu 18'
when: ansible_distribution != 'Ubuntu'
- name: update and install apache
apt: # https://docs.ansible.com/ansible/latest/modules/apt_module.html
name: "{{ package_apache }}"
update_cache: yes
state: present
notify:
- debug message for apache installation
- restart and enable apache2
- name: install php modules
apt:
name: "{{ item }}"
state: present
loop: "{{ packages_php_modules}}"
notify:
- debug message for php modules
- restart and enable apache2
handlers:
- name: restart and enable apache2
service:
name: "{{ package_apache }}"
enabled: yes
state: restarted
- name: debug message for apache installation
debug:
msg: "{{ package_apache }} is installed"
- name: debug message for php modules
debug:
msg: "php modules are installed"
- We have one last step of creating a file called as info.php in /var/www/html/info.php with following content
<?php
phpinfo();
?>
- This step means we have to create a file. Creating a file can be done into two ways
- If the file is available on some url download the file
- Copy the file from your system into server whereever you want to run
- For file demo use this playbook
---
- hosts: all
tasks:
- name: create an empty file # This module creates an empty file on node
file:
path: /home/devops/readme.txt
state: touch
- name: copy the files on your server # This module creates a symlink between two files on the node
file:
src: /home/devops/readme.txt
dest: /home/devops/readmecopy.txt
state: link
- name: create directory # This module creates empty directory on node
file:
path: /home/devops/temp
state: directory
- name: download file from url # This module downloads the file from url into node
get_url:
url: https://war-jar-files.s3-us-west-2.amazonaws.com/gameoflife.war
dest: /home/devops/gameoflife.war
- name: copy the file from acs to node # This module copies the file from acs to node
copy:
src: demo.txt
dest: /home/devops/demo.txt
- Create info.php in the folder where you are writing playbook with following content
<?php
phpinfo();
?>
- Now use copy module to copy this info.php to node and the playbook looks like below
---
- hosts: webservers
become: yes
vars:
package_apache: apache2
packages_php_modules:
- php
- libapache2-mod-php
- php-mysql
- php-cli
tasks:
- name: fail playbook on unsupported platforms
fail:
msg: 'This playbook is currently developed only for ubuntu 18'
when: ansible_distribution != 'Ubuntu'
- name: update and install apache
apt: # https://docs.ansible.com/ansible/latest/modules/apt_module.html
name: "{{ package_apache }}"
update_cache: yes
state: present
notify:
- debug message for apache installation
- restart and enable apache2
- name: install php modules
apt:
name: "{{ item }}"
state: present
loop: "{{ packages_php_modules}}"
notify:
- debug message for php modules
- restart and enable apache2
- name: copy info.php
copy:
src: info.php
dest: /var/www/html/info.php
notify:
- restart and enable apache2
handlers:
- name: restart and enable apache2
service:
name: "{{ package_apache }}"
enabled: yes
state: restarted
- name: debug message for apache installation
debug:
msg: "{{ package_apache }} is installed"
- name: debug message for php modules
debug:
msg: "php modules are installed"
-
After this navigate to url http://<publicip>/info.php and you should see the php test page.
-
Exercise: Make this work for centos 7 as well using docs over here
-
In the next class we would configure tomcat on linux machines and learn the subsequent ansible topics along with that.
