Ansible Roles using ansible-galaxy

 Ansible Roles :

• Roles are consist of more than one playbooks like modules in puppet and cook books in Chef.
• Roles are used to perform mulitple tasks under one container with clean and neat directory structure.
• Roles are set of tasks and additional files to breakup the configuration for easy handling
• Tasks under role can be used by anyone if those rules/tasks maches with their needs.

What is Ansible Galaxy?

Ansible Galaxy is used to initiate a role which will create respective directory structure under that the role name.

How to initiate a role using Galaxy?

Command to initiate the role using Galaxy is  

ansible-galaxy init <directory path>

Eg:

ansible-galaxy init /etc/ansible/roles/apache

Now let us create the tasks

Go to /etc/ansible/roles/apache/tasks

vi  main.yml

Above tasks does take care of installing httpd (apache) service, copying index.html to target server, starting service and enabling at the boot config.

In single task file we are performing more than one task, this can be done it through mulple yml files and then we can import all the yml files into tasks using below syntax

 Install.yml will look like below

---

      - name: Install apache httpd package

      - yum: name=httpd state=latest

Configure.yml will look like below

---

- name: copy httpd.conf file to the target servers

  copy: src=files/httpd.cfg dest=/etc/httpd/conf/httpd.cfg

- name: copy index.html to the target servers 

  copy: src=files/index.html desk=/var/www/index.html

   notify:

   - retart apache

             Note: src files kept it in 'files' directory so make sure you keep the httpd.cfg and index.html in that directory

service.yml will look like below

---

- name: enable service to come up during reboot

  service: name=httpd state=restarted enabled=yes

Next

Now you can update the meta data main.yml with author, purpose of this playbook, version, date etc

Restarting httpd service whenever there is any configuration change can be updated into hander section of the role.

Finally, we can create Run.yml to call the apache role to execute the underneath tasks

Run.yml

---

  - hosts: all/node1    (all means calling inventory)

  - roles: 

  - apache

if you want to call more than one role then mention all of them one by one

Execution:

validation

ansible-playbook  Run.yml  --syntax-check

ansible-playbook Run.yml