Ansible Tutorial - How To Define a Ansible Register Variable in Playbook

Ansible Tutorial - How To Define a Ansible Register Variable in Playbook

Tags: ansible register variable, ansible, ansible tutorial, ansible ansible certification, ansible tags, ansible tasks, ansible modules, ansible debug, ansible inventory, ansible hosts file, ansible facts,ansible playbook tutorial, ansible linux, ansible best practices
Ansible registers module used to capture / store the output of a task/command.it is similar to variable declarations we can define the value in different scenarios like a conditional, logging etc.



for example we echo uptime and hostname, Following Syntax :

register: uptime

Here uptime is value of register variable, we can define any suitable value. At the last we use debug module with variable name.  

To create a playbook with suitable name, we create a register.yml file under ansible configuration directory
cd /etc/ansiblevi register.yml
---
- hosts: all
  tasks:
  - name: System Uptime
    command: uptime
    register: uptime

  - debug: var=uptime

-name: System Uptime  is a task name, 
command: uptime  , command is module name and uptime is linux system command
register: uptime , uptime is register variable value, we can use any suitable value 

To run playbook using ansible-playbook command, for help of ansible-playbook you can use -h option
ansible-playbook  -h
To run ansible playbook
ansible-playbook registe.yml
To run ansible playbook on single hosts of inventory using  -l option,


172.17.20.98 is hosts IP of our Ansible Inventery
ansible-playbook -l 172.17.20.98 register.yml
We can add stderr, stderr_lines, stdout, stdout_lines for filter

We will use stdout for filter the result, something like this example

Video Tutorial : 


---
- hosts: all
  tasks:
  - name: System Uptime
    command: uptime
    register: uptime

  - debug: var=uptime.stdout

Multiple register variable :

---
- hosts: 127.0.0.1

  tasks:
  - name: System Uptime
    command: uptime
    register: uptime

  - name: System Hostname
    command: hostname
    register: host

  - debug: var={{ item }}
    loop:
      - uptime.stdout
      - host.stdout


ansible-playbook registe.yml



Thanks

End of this ansible register variables tutorial,  we need your support so i request you to please comment if something missed by me, and share and like this post aslo 


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