Ansible telnet without username login

Question

I need to connect to cisco devices with ansible telnet module (I can't enable SSH). In all the tutorial I found on the web, everyone is specifying a login username and a password for authenticating in telnet.

But my router doesn't have a username need, the auth prompt start directly with the mesage :

Password:

Here's my files :

inventory.yml :

[cisco]
test ip_address=xxx.yyy.zzz

[cisco:vars]
password=test
password_enable=test

plays/cisco.yml :

---

- hosts: cisco
  connection: local
  roles:
    - role: cisco-telnet

roles/cisco-telnet/tasks/main.yml :

---
- name: Telnet test
  telnet:
    host: "{{ ip_address }}"
    port: 23
    password_prompt: "Password:"
    password: "{{ password }}"
    prompts:
      - '[>|#]'
    command:
      - enable
      - "{{ password_enable }}"
      - show running-config

I got an error message everytime :

FAILED! => {
    "msg": "Unexpected failure during module execution.",
    "stdout": ""
}

How can I use telnet module without specifying a username ? Someone already did that ?

Answer 1

Studying the source code of the telnet module and reading the documentation I assume the follwing behaviour:

If the password is empty then no password prompt is expected.

It follows that you can use the login prompt for the password. Somewhat strange, so I guess the following code snippet should work:

- name: Telnet test
  telnet:
    host: "{{ ip_address }}"
    port: 23
    login_prompt: "Password:"
    user: "{{ password }}"
    prompts:
      - '[>|#]'
    command:
      - enable
      - "{{ password_enable }}"
      - show running-config

I can't test it because I do not have a telnet server anymore, you are 20 years late ;-)