What you'll learn
- Introduction
- The Demo
- Understanding the Error
- Verbose Execution
- Fixing the Code
- Successful Execution
- Conclusion
- Common Causes
- Wrong parameter name
- Module version mismatch
Introduction
Welcome to another episode of Ansible Pilot! I'm Luca Berton, and today we'll delve into Ansible troubleshooting, focusing on the infamous "Invalid Argument" error. This error commonly occurs when using the Ansible `file` module to create a symlink in a Linux environment. Let's explore how to reproduce, troubleshoot, and fix this issue.
The Demo
To better understand Ansible troubleshooting, let's dive into a live Playbook. We'll create a playbook (`invalidargument_error.yml`) that attempts to create a symbolic link using the `file` module. In this example, we're trying to symlink `/proc/cpuinfo` to `~/example`.
```yaml
---
- name: file module demo
hosts: all
vars:
mylink: "~/example"
mysrc: "/proc/cpuinfo"
tasks:
- name: Creating a symlink
ansible.builtin.file:
path: "{{ mylink }}"
dest: "{{ mysrc }}"
state: link
```
Executing this playbook (`ansible-playbook -i inventory invalidargument_error.yml`) results in the following error:
```bash
TASK [Creating a symlink] ******************************************************
An exception occurred during task execution.
OSError: [Errno 22] Invalid argument: b'/proc/cpuinfo'
```
Understanding the Error
The error is clear: "OSError: [Errno 22] Invalid argument." This occurs because the `file` module expects a valid source (`src`) and destination (`dest`) when creating a symlink. In our original playbook, we only provided the `path` and `dest` parameters, leading to the "Invalid argument" error.
Verbose Execution
Executing the playbook with increased verbosity (`-vvv`) provides a more detailed traceback, helping us pinpoint the issue:
```bash
ansible-playbook -i inventory invalidargument_error.yml -vvv
```
The output reveals the exact error in the `file` module, emphasizing the need for a valid source parameter.
Fixing the Code
To resolve the "Invalid Argument" error, we need to correct our playbook. The fixed playbook (`invalidargument_fix.yml`) includes the missing `src` parameter:
```yaml
---
- name: file module demo
hosts: all
vars:
mylink: "~/example"
mysrc: "/proc/cpuinfo"
tasks:
- name: Creating a symlink
ansible.builtin.file:
src: "{{ mysrc }}"
dest: "{{ mylink }}"
state: link
```
Successful Execution
Executing the fixed playbook (`ansible-playbook -i inventory invalidargument_fix.yml`) should now complete without errors:
```bash
PLAY [file module demo] ***************************************************************************
TASK [Gathering Facts] ****************************************************************************
ok: [demo.example.com]
TASK [Creating a symlink] *************************************************************************
ok: [demo.example.com]
PLAY RECAP ****************************************************************************************
demo.example.com : ok=2 changed=0 unreachable=0 failed=0 skipped=0 rescued=0 i