Command passes, but why is result in stderr and not stdout?

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1

I have the following simple task to check my Python version

`

  • name: Check if Python version matches target

commadn: “/local/python/bin/python --version”
register: python_ver_check

  • debug: var=python_ver_check

`

and I get

`
TASK [python3 : debug] *********************************************************
ok: [localhost] => {
“python_ver_check”: {
“changed”: true,
“cmd”: “/local/python/bin/python --version”,
“delta”: “0:00:00.003369”,
“end”: “2017-10-31 14:00:10.701899”,
“failed”: false,
“rc”: 0,
“start”: “2017-10-31 14:00:10.698530”,
“stderr”: “Python 2.7.14”,
“stderr_lines”: [
“Python 2.7.14”
],
“stdout”: “”,
“stdout_lines”:
}
}

`

Why stderr and not stdout? The task executed with no errors.

2

That is where python has decided the version output should go. It is specifically sent to stderr by the python binary.

3

Also, fwiw, look at the ansible_python or ansible_python_version variables created during fact gathering, that may be useful to you.

4

Thanks!

5

How do I force Ansible to use a certain version of Python? Is it in the ansible.cfg file? For example, I see via “ansible --version” command that it’s using /usr/local/bin/python v2.6.6, but I want it to use /local/python/bin/python v2.7.x for example?