Spent some time tinkering at home on Saturday; all processes below have been gradually experimented and implemented;

This article is based on practical operations and organized with ChatGPT, aiming to help readers quickly master the practical methods of Ansible in a local environment simulating multi-hosts with Docker.

Market Share and Value of Ansible
Getting Started with Ansible and Installation Debugging on Windows/WSL
Multi-Host Simulation with Ansible (Docker Solution)
Debugging Docker Containers and Bulk Tool Installation
Summary and Extension Suggestions

1. Market Share and Value of Ansible

Question

Is Ansible’s market share high? Is it worth learning? What problems does it mainly solve?

Market Data (2025)

Ansible: Market share 31.45%, ranking second among configuration management tools, second only to Terraform, higher than Puppet and Chef.
Red Hat Ansible Automation Platform: Market share 16.8%, still one of the mainstream solutions for enterprise automation.

Learning Value

Gentle learning curve, Agentless (no need to install agents on clients)
Deep integration with Python, strong script extension capabilities
Widely used in DevOps, cloud automation, network device management
Stable demand for Ansible talent in medium to large enterprises

Main Applicable Scenarios

Configuration management (unifying server environments)
Application deployment (rolling updates, blue-green releases)
IaC (Infrastructure as Code)
Task automation (batch operations, monitoring, backups)
CI/CD process integration
Network automation (Cisco/Juniper and other devices)
Consistency across development, testing, and production environments

💡 Suggestions

Use AI to assist in generating learning paths and practice hands-on with official documentation
Start with the smallest Playbook (e.g., disk check) and then expand to multiple nodes
Practice repeatedly in local + test server environments to improve portability

2. Getting Started with Ansible and Installation Debugging on Windows/WSL

Quick Start Example: Disk Space Check

inventory.ini

[local]
localhost ansible_connection=local

playbook.yml

---
- name: Check Disk Space
  hosts: local
  tasks:
    - name: Get disk usage
      ansible.builtin.shell: df -h
      register: disk_output

    - name: Display disk report
      ansible.builtin.debug:
        msg: "{{ disk_output.stdout }}"

Run Command

ansible-playbook -i inventory.ini playbook.yml

Common Issues in Windows/WSL Environment Debugging

Native installation on Windows may encounter Blocking IO errors
apt command may be unavailable (missing WSL configuration)

Solutions

# Install WSL and Ubuntu
wsl --install -d Ubuntu

# Update system and install Ansible
sudo apt update &amp;&amp; sudo apt upgrade -y
sudo apt install ansible -y

Experience Tips

Avoid executing control node tasks directly on Windows; it is recommended to use WSL/Linux
If Docker Desktop is installed, check WSL integration in the top right corner gear → Resources for easier visual management of containers

3. Multi-Host Simulation with Ansible (Docker Solution)

Dockerfile (Ubuntu with SSH)

FROM ubuntu:latest
RUN apt-get update &amp;&amp; \
    apt-get install -y openssh-server sudo &amp;&amp; \
    mkdir /var/run/sshd &amp;&amp; \
    useradd -m -s /bin/bash ansibleuser &amp;&amp; \
    echo "ansibleuser:password" | chpasswd &amp;&amp; \
    echo "ansibleuser ALL=(ALL) NOPASSWD: ALL" &gt;&gt; /etc/sudoers &amp;&amp; \
    ssh-keygen -A

CMD ["/usr/sbin/sshd", "-D"]

Build and Start Multiple Containers

docker build -t ansible-ubuntu .

for i in {1..10}; do
  PORT=$((2200 + i))
  docker run -d -p $PORT:22 --name host$i ansible-ubuntu
done

Inventory Configuration (multi-hosts.ini)

[simulate_hosts]
host1 ansible_host=127.0.0.1 ansible_port=2201 ansible_user=ansibleuser ansible_password=password
# host2...host10 incrementing ports

Ansible Configuration Optimization~/.ansible.cfg

[defaults]
host_key_checking = False
timeout = 30

Test Connectivity

ansible -i multi-hosts.ini simulate_hosts -m ping

4. Debugging Docker Containers and Bulk Tool Installation

Playbook for Bulk Installation of Common Tools

---
- name: Install Common Tools on Simulate Hosts
  hosts: simulate_hosts
  become: yes
  tasks:
    - name: Update apt cache
      ansible.builtin.apt:
        update_cache: yes
        cache_valid_time: 3600

    - name: Install common tools
      ansible.builtin.apt:
        name:
          - net-tools
          - iproute2
          - iputils-ping
          - htop
          - vim
          - tcpdump
          - curl
          - wget
        state: present

    - name: Verify installation
      ansible.builtin.shell: htop -V
      register: htop_output
      ignore_errors: yes

    - name: Display result
      ansible.builtin.debug:
        msg: "{{ htop_output.stdout | default('htop not installed') }}"

Run Command

ansible-playbook -i multi-hosts.ini install_tools.yml --ask-become-pass

Note: The Ubuntu image in Docker is a minimal version, and some services that depend on systemd cannot run.

5. Summary and Extension Suggestions

Ansible Practical Experience

Quickly set up a testing environment using WSL + Docker
Add -vvv during debugging to view detailed logs
Separate management of Inventory and Playbook

Docker Usage Experience

Minimal images require manual completion of tools
To keep containers running long-term:

CMD ["tail", "-f", "/dev/null"]
# or
sshd -D

Common Issues

YAML indentation errors causing Playbook execution failures
SSH fingerprint check blocking the first connection (need to disable host_key_checking)
When systemd is missing, lightweight alternatives need to be used

Extension Directions

Use Ansible to manage Docker container lifecycle
Integrate automated build and deployment pipelines (CI/CD)
Use Molecule for automated testing of Playbooks

Initial Experience with Ansible Automation Tool (Simulating Multi-Host with Docker)