For more information regarding the security incident at F5, the actions we are taking to address it, and our ongoing efforts to protect our customers, click here.

Forum Discussion

Thornid's avatar
Thornid
Icon for Nimbostratus rankNimbostratus
Jul 24, 2020

Basic Question on Ansible - Creating Nodes

Hello all

I know this is basic but I'm starting off learning about Ansible and F5s. I'm following this lab guide:

https://github.com/ansible/workshops/tree/devel/exercises/ansible_f5/1.2-add-node

I have configured a basic inventory as such:

[lb]
f5 ansible_host=X.X.X.X ansible_user=admin private_ip=X.X.X.X ansible_ssh_pass=XXXXXXXX

[webservers]
host1 ansible_host=X.X.X.X
host2 ansible_host=X.X.X.X

I then have my YAML file as follows:

---
- name: BIG-IP SETUP
 hosts: lb
 connection: local
 gather_facts: false

 tasks:

 - name: CREATE NODES
   bigip_node:
     provider:
       server: X.X.X.X
       user: XXXX
       password: XXXXXXX
       server_port: 443
       validate_certs: false
     host: "{{hostvars[webservers].ansible_host}}"
     name: "{{hostvars[webservers].inventory_hostname}}"
   loop: "{{ groups[webservers] }}"

When I try to run this playbook I get the following error:

devlin@ubuntu-v20:~/ansible/f5/lab2$ ansible-playbook -i inventory bigip-node.yaml

PLAY [BIG-IP SETUP] *****************************************************************************************************************

TASK [CREATE NODES] *****************************************************************************************************************
fatal: [f5]: FAILED! => {"msg": "'webservers' is undefined"}

PLAY RECAP **************************************************************************************************************************
f5                        : ok=0   changed=0   unreachable=0   failed=1   skipped=0   rescued=0   ignored=0

What does it mean "webservers is undefined"?

Thank you?

Ansible
application delivery
BIG-IP
devops

4 Replies

  • Thornid's avatar
    Thornid
    Icon for Nimbostratus rankNimbostratus
    Jul 24, 2020

    Thanks ArvinF

    Even if I explicitly tell the playbook which inventory file I get the same thing:

    devlin@ubuntu-v20:~/ansible/f5/lab2$ ansible-playbook -i ~/ansible/f5/lab2/inventory bigip-node-3.yaml -vvv
ansible-playbook 2.9.6
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/devlin/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3/dist-packages/ansible
  executable location = /usr/bin/ansible-playbook
  python version = 3.8.2 (default, Jul 16 2020, 14:00:26) [GCC 9.3.0]
Using /etc/ansible/ansible.cfg as config file
host_list declined parsing /home/devlin/ansible/f5/lab2/inventory as it did not pass its verify_file() method
script declined parsing /home/devlin/ansible/f5/lab2/inventory as it did not pass its verify_file() method
auto declined parsing /home/devlin/ansible/f5/lab2/inventory as it did not pass its verify_file() method
Parsed /home/devlin/ansible/f5/lab2/inventory inventory source with ini plugin
 
PLAYBOOK: bigip-node-3.yaml ************************************************************************************************************************************************************************************************
1 plays in bigip-node-3.yaml
 
PLAY [BIG-IP SETUP] ********************************************************************************************************************************************************************************************************
META: ran handlers
 
TASK [CREATE NODES] ********************************************************************************************************************************************************************************************************
task path: /home/devlin/ansible/f5/lab2/bigip-node-3.yaml:9
fatal: [f5]: FAILED! => {
    "msg": "The task includes an option with an undefined variable. The error was: \"hostvars['webservers']\" is undefined\n\nThe error appears to be in '/home/devlin/ansible/f5/lab2/bigip-node-3.yaml': line 9, column 5, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n\n  - name: CREATE NODES\n    ^ here\n"
}
 
PLAY RECAP *****************************************************************************************************************************************************************************************************************
f5                         : ok=0    changed=0    unreachable=0    failed=1    skipped=0    rescued=0    ignored=0
    • cjunior's avatar
      cjunior
      Icon for Nacreous rankNacreous
      Jul 24, 2020

      Hello,

      I think you must loop on "webservers" group and interact on each "item":

      ---
- name: BIG-IP SETUP
 hosts: lb
 connection: local
 gather_facts: false
 
 tasks:
 
 - name: CREATE NODES
   bigip_node:
     provider:
       server: X.X.X.X
       user: XXXX
       password: XXXXXXX
       server_port: 443
       validate_certs: false
     host: "{{hostvars[item].ansible_host}}"
     name: "{{hostvars[item].inventory_hostname}}"
   loop: "{{ groups[webservers] }}"

      Regards.

  • Thornid's avatar
    Thornid
    Icon for Nimbostratus rankNimbostratus
    Jul 25, 2020

    Hi cjunior

     

    You were spot on, thank you very much. Reading the various Ansible documentation and blog posts I convinced myself the hostvars must refer to an actual name in the inventory. But looking at it like this, it makes much more sense now.