register:

• Used to register variables defined in a module when it is invoked in a task
• The registered data is stored in JSON format
• The value of the variables set using the register clause is always a dictionary, but the specific keys of the dictionary are different, depending on the module that was invoked.
• Every module will have a different dictionary of variables that it will try to gather from the host.
• Below example shows the three dictionary values that were registered when using backup parameter in ios_config module.

ok: [coresw03] => {
"result": {
"backup_path": "/etc/ansible/roles/cisco_ios/backup/coresw03_config.2019-04-28@13:40:06", 
"changed": false, 
"failed": false
}
}

---

debug:
  msg:

• Used to display the variables registered using the register clause.
• The registered variable is referenced within {{ }} when using the msg parameter.
• This can be used along with a regular message string to provide more context to the variable’s specific dictionary key that was registered.
• To reference only a specific key in the dictionary append the registered variable with the dictionary key that you want to display;

{{ result.backup_path }}

• The msg paramter supports array, so you can reference multiple keys in the same task;

msg:
  - "Backup path is {{ result.backup_path }}"
  - "Changed: {{ result.changed }}"

---

debug:
  var:

• Used to display the variables registered using the register clause.
• Outputs the variable in raw format and cannot provide any context to the variable’s specific dictionary key that was registered.
• To reference only a specific key in the dictionary append the registered value with the dictionary key that you want to display;

result.backup_path

• The var parameter doesn’t support array. So you cannot reference multiple keys in the same task.

Note:

debug: var and debug: msg are mutually exclusive and cannot be used together in the same task. But they can be used in separate tasks under the same play.

 

---

Playbook1 using msg parameter:

- name: Running task_backup_cisco_ios_v3.yaml from /etc/ansible/roles/cisco_ios/tasks directory
  ios_config:
    backup: yes
  register: result

- name: Capture directory where backup file is stored
  debug:
    msg: "The backup file is saved in {{ result.backup_path }}"

Playbook1 output:

shoaib@ubndsk01:~/Desktop/ansible/projects/project_backup$ ansible-playbook pb_backup_cisco_ios_v1.yml

PLAY [Running pb_backup_cisco_ios_v1.yml from ~/Desktop/ansible/projects/project_backup directory] ************************************************************************************************************

TASK [cisco_ios : Running task_backup_cisco_ios_v3.yaml from /etc/ansible/roles/cisco_ios/tasks directory] ****************************************************************************************************
ok: [coresw03]

TASK [cisco_ios : Capture directory where backup file is stored] **********************************************************************************************************************************************
ok: [coresw03] => {
    "msg": "The backup file is saved in /etc/ansible/roles/cisco_ios/backup/coresw03_config.2019-04-28@13:26:18"
}

PLAY RECAP ****************************************************************************************************************************************************************************************************
coresw03                   : ok=2    changed=0    unreachable=0    failed=0  

 

---

Playbook 2 using var parameter:

- name: Running task_backup_cisco_ios_v3.yaml from /etc/ansible/roles/cisco_ios/tasks directory
ios_config:
backup: yes
register: result

- name: Capture directory where backup file is stored
debug:
var: result.backup_path

Playbook2 output:

shoaib@ubndsk01:~/Desktop/ansible/projects/project_backup$ ansible-playbook pb_backup_cisco_ios_v1.yml

PLAY [Running pb_backup_cisco_ios_v1.yml from ~/Desktop/ansible/projects/project_backup directory] ************************************************************************************************************

TASK [cisco_ios : Running task_backup_cisco_ios_v3.yaml from /etc/ansible/roles/cisco_ios/tasks directory] ****************************************************************************************************
ok: [coresw03]

TASK [cisco_ios : Capture directory where backup file is stored] **********************************************************************************************************************************************
ok: [coresw03] => {
"result.backup_path": "/etc/ansible/roles/cisco_ios/backup/coresw03_config.2019-04-28@13:27:48"
}

PLAY RECAP ****************************************************************************************************************************************************************************************************
coresw03 : ok=2 changed=0 unreachable=0 failed=0 

 

---

Playbook 3 using ‘msg’ and ‘var’ in the same play but under different tasks:

- name: Running task_backup_cisco_ios_v3.yaml from /etc/ansible/roles/cisco_ios/tasks directory
  ios_config:
    backup: yes
  register: result

- name: Capture directory where backup file is stored
  debug:
    var: result.backup_path

- name: Capture directory where backup file is stored
  debug:
    msg: "The backup file is saved in {{ result.backup_path }}"

Playbook 3 output:

shoaib@ubndsk01:~/Desktop/ansible/projects/project_backup$ ansible-playbook pb_backup_cisco_ios_v1.yml

PLAY [Running pb_backup_cisco_ios_v1.yml from ~/Desktop/ansible/projects/project_backup directory] ************************************************************************************************************

TASK [cisco_ios : Running task_backup_cisco_ios_v3.yaml from /etc/ansible/roles/cisco_ios/tasks directory] ****************************************************************************************************
ok: [coresw03]

TASK [cisco_ios : Capture directory where backup file is stored] **********************************************************************************************************************************************
ok: [coresw03] => {
    "result.backup_path": "/etc/ansible/roles/cisco_ios/backup/coresw03_config.2019-04-28@13:29:06"
}

TASK [cisco_ios : Capture directory where backup file is stored] **********************************************************************************************************************************************
ok: [coresw03] => {
    "msg": "The backup file is saved in /etc/ansible/roles/cisco_ios/backup/coresw03_config.2019-04-28@13:29:06"
}

PLAY RECAP ****************************************************************************************************************************************************************************************************
coresw03                   : ok=3    changed=0    unreachable=0    failed=0