In this post, I am discussing troubleshooting of Ansible playbooks. Ansible provides several methods for managing playbooks. These include log configuration, specifying options like --step, -v, and controlling playbook execution using modules like fail or assert.

Log File Configuration

Unfortunately, logging is not configured in Ansible by default. However, we can configure it. There are two ways to activate logging:

There are two ways to activate logging:

  • Set log_path parameter in default section of ansible.cfg file
cat ansible.cfg
[default]
log_path = /var/log/ansible-logs/ansible.log
  • set environment variable $ANSIBLE_LOG_PATH

NOTE: It is strongly recommended to use logrotate to manage the logs if they will be written in /var/log directory.

Managing problems

--syntax-check - checks the syntax in the playbook

ansible-playbook myplay.yml --syntax-check

--step - using this option we can step to a specific task in a playbook

ansible-playbook myplay.yml --step

--start-at-task - with this option we can start execution of a playbook from a specific task

ansible-playbook myplay.yml --start-at-task

Verbosity can be increased for debugging using -v parameter, with four levels of verbosity: -v, --vv, --vvv, --vvvv.

--check (or -C) executes a playbook without making changes to the managed host. You can control this option individually:

  • Always run in check mode:
- name: always run in check mode
  shell: hostname
  check_mode: yes
  • Do not run in check mode, even if --check is specified:
- name: always run in check mode
  shell: hostname
  check_mode: no

--diff shows changes made to template files:

ansible-playbook myplay.yml --check --diff

Expample Troubleshooting using modules

script module executes a script against managed hosts. This script have to locate on the control node. Executing fails if script ends with the non-zero code.


  tasks:
    - name: Run my script 
      script: run_my_script

uri module helps to check some http services


  tasks:
    - name: check my API
      uri:
        url: http://myapi.home.lab
        return_content: yes
      register: answer

    - fail:
        msg: 'Service is not up'
      when: "'UP' not in answer.content"

stat - collects information about files and folders


  tasks:
    - name: Check if /opt/app/hello.py file exists
      stat:
        path: /opt/app/hello.py
      register: answer

    - name: hello.py file does not exist
      fail:
      when: answer.stat.exists

The assert module can be used as an alternative to the fail module:


  tasks:
    - name: Check if /opt/app/hello.py file exists
      stat:
        path: /opt/app/hello.py
      register: answer

    - name: hello.py file does not exist
      assert:
        that:
          - not answer.stat.exists

This note provides insight into some methods and modules for troubleshooting Ansible playbooks based on personal experiences.

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