Ansible

Ansible Skill

Infrastructure as Code automation for server provisioning, configuration management, and orchestration.

Quick Start

Prerequisites

# Install Ansible
pip install ansible

# Or on macOS
brew install ansible

# Verify
ansible --version

Run Your First Playbook

# Test connection
ansible all -i inventory/hosts.yml -m ping

# Run playbook
ansible-playbook -i inventory/hosts.yml playbooks/site.yml

# Dry run (check mode)
ansible-playbook -i inventory/hosts.yml playbooks/site.yml --check

# With specific tags
ansible-playbook -i inventory/hosts.yml playbooks/site.yml --tags "security,nodejs"

Directory Structure

skills/ansible/
├── SKILL.md              # This file
├── inventory/            # Host inventories
│   ├── hosts.yml         # Main inventory
│   └── group_vars/       # Group variables
├── playbooks/            # Runnable playbooks
│   ├── site.yml          # Master playbook
│   ├── openclaw-vps.yml  # OpenClaw VPS setup
│   └── security.yml      # Security hardening
├── roles/                # Reusable roles
│   ├── common/           # Base system setup
│   ├── security/         # Hardening (SSH, fail2ban, UFW)
│   ├── nodejs/           # Node.js installation
│   └── openclaw/         # OpenClaw installation
└── references/           # Documentation
    ├── best-practices.md
    ├── modules-cheatsheet.md
    └── troubleshooting.md

Core Concepts

Inventory

Define your hosts in inventory/hosts.yml:

all:
  children:
    vps:
      hosts:
        eva:
          ansible_host: 217.13.104.208
          ansible_user: root
          ansible_ssh_pass: "{{ vault_eva_password }}"
        plane:
          ansible_host: 217.13.104.99
          ansible_user: asdbot
          ansible_ssh_private_key_file: ~/.ssh/id_ed25519_plane
    
    openclaw:
      hosts:
        eva:

Playbooks

Entry points for automation:

# playbooks/site.yml - Master playbook
---
- name: Configure all servers
  hosts: all
  become: yes
  roles:
    - common
    - security

- name: Setup OpenClaw servers
  hosts: openclaw
  become: yes
  roles:
    - nodejs
    - openclaw

Roles

Reusable, modular configurations:

# roles/common/tasks/main.yml
---
- name: Update apt cache
  ansible.builtin.apt:
    update_cache: yes
    cache_valid_time: 3600
  when: ansible_os_family == "Debian"

- name: Install essential packages
  ansible.builtin.apt:
    name:
      - curl
      - wget
      - git
      - htop
      - vim
      - unzip
    state: present

Included Roles

1. common

Base system configuration:

• System updates
• Essential packages
• Timezone configuration
• User creation with SSH keys

2. security

Hardening following CIS benchmarks:

• SSH hardening (key-only, no root)
• fail2ban for brute-force protection
• UFW firewall configuration
• Automatic security updates

3. nodejs

Node.js installation via NodeSource:

• Configurable version (default: 22.x LTS)
• npm global packages
• pm2 process manager (optional)

4. openclaw

Complete OpenClaw setup:

• Node.js (via nodejs role)
• OpenClaw npm installation
• Systemd service
• Configuration file setup

Usage Patterns

Pattern 1: New VPS Setup (OpenClaw)

# 1. Add host to inventory
cat >> inventory/hosts.yml << 'EOF'
        newserver:
          ansible_host: 1.2.3.4
          ansible_user: root
          ansible_ssh_pass: "initial_password"
          deploy_user: asdbot
          deploy_ssh_pubkey: "ssh-ed25519 AAAA... asdbot"
EOF

# 2. Run OpenClaw playbook
ansible-playbook -i inventory/hosts.yml playbooks/openclaw-vps.yml \
  --limit newserver \
  --ask-vault-pass

# 3. After initial setup, update inventory to use key auth
# ansible_user: asdbot
# ansible_ssh_private_key_file: ~/.ssh/id_ed25519

Pattern 2: Security Hardening Only

ansible-playbook -i inventory/hosts.yml playbooks/security.yml \
  --limit production \
  --tags "ssh,firewall"

Pattern 3: Rolling Updates

# Update one server at a time
ansible-playbook -i inventory/hosts.yml playbooks/update.yml \
  --serial 1

Pattern 4: Ad-hoc Commands

# Check disk space on all servers
ansible all -i inventory/hosts.yml -m shell -a "df -h"

# Restart service
ansible openclaw -i inventory/hosts.yml -m systemd -a "name=openclaw state=restarted"

# Copy file
ansible all -i inventory/hosts.yml -m copy -a "src=./file.txt dest=/tmp/"

Variables & Secrets

Group Variables

# inventory/group_vars/all.yml
---
timezone: Europe/Budapest
deploy_user: asdbot
ssh_port: 22

# Security
security_ssh_password_auth: false
security_ssh_permit_root: false
security_fail2ban_enabled: true
security_ufw_enabled: true
security_ufw_allowed_ports:
  - 22
  - 80
  - 443

# Node.js
nodejs_version: "22.x"

Vault for Secrets

# Create encrypted vars file
ansible-vault create inventory/group_vars/all/vault.yml

# Edit encrypted file
ansible-vault edit inventory/group_vars/all/vault.yml

# Run with vault
ansible-playbook site.yml --ask-vault-pass

# Or use vault password file
ansible-playbook site.yml --vault-password-file ~/.vault_pass

Vault file structure:

# inventory/group_vars/all/vault.yml
---
vault_eva_password: "y8UGHR1qH"
vault_deploy_ssh_key: |
  -----BEGIN OPENSSH PRIVATE KEY-----
  ...
  -----END OPENSSH PRIVATE KEY-----

Common Modules

Best Practices

1. Always Name Tasks

# Good
- name: Install nginx web server
  apt:
    name: nginx
    state: present

# Bad
- apt: name=nginx

2. Use FQCN (Fully Qualified Collection Names)

# Good
- ansible.builtin.apt:
    name: nginx

# Acceptable but less clear
- apt:
    name: nginx

3. Explicit State

# Good - explicit state
- ansible.builtin.apt:
    name: nginx
    state: present

# Bad - implicit state
- ansible.builtin.apt:
    name: nginx

4. Idempotency

Write tasks that can run multiple times safely:

# Good - idempotent
- name: Ensure config line exists
  ansible.builtin.lineinfile:
    path: /etc/ssh/sshd_config
    regexp: '^PasswordAuthentication'
    line: 'PasswordAuthentication no'

# Bad - not idempotent
- name: Add config line
  ansible.builtin.shell: echo "PasswordAuthentication no" >> /etc/ssh/sshd_config

5. Use Handlers for Restarts

# tasks/main.yml
- name: Update SSH config
  ansible.builtin.template:
    src: sshd_config.j2
    dest: /etc/ssh/sshd_config
  notify: Restart SSH

# handlers/main.yml
- name: Restart SSH
  ansible.builtin.systemd:
    name: sshd
    state: restarted

6. Tags for Selective Runs

- name: Security tasks
  ansible.builtin.include_tasks: security.yml
  tags: [security, hardening]

- name: App deployment
  ansible.builtin.include_tasks: deploy.yml
  tags: [deploy, app]

Troubleshooting

Connection Issues

# Test SSH connection manually
ssh -v user@host

# Debug Ansible connection
ansible host -i inventory -m ping -vvv

# Check inventory parsing
ansible-inventory -i inventory --list

Common Errors

"Permission denied"

• Check SSH key permissions: chmod 600 ~/.ssh/id_*
• Verify user has sudo access
• Add become: yes to playbook

"Host key verification failed"

• Add to ansible.cfg: host_key_checking = False
• Or add host key: ssh-keyscan -H host >> ~/.ssh/known_hosts

"Module not found"

• Use FQCN: ansible.builtin.apt instead of apt
• Install collection: ansible-galaxy collection install community.general

Debugging Playbooks

# Verbose output
ansible-playbook site.yml -v    # Basic
ansible-playbook site.yml -vv   # More
ansible-playbook site.yml -vvv  # Maximum

# Step through tasks
ansible-playbook site.yml --step

# Start at specific task
ansible-playbook site.yml --start-at-task="Install nginx"

# Check mode (dry run)
ansible-playbook site.yml --check --diff

Integration with OpenClaw

From OpenClaw Agent

# Run playbook via exec tool
exec command="ansible-playbook -i skills/ansible/inventory/hosts.yml skills/ansible/playbooks/openclaw-vps.yml --limit eva"

# Ad-hoc command
exec command="ansible eva -i skills/ansible/inventory/hosts.yml -m shell -a 'systemctl status openclaw'"

Storing Credentials

Use OpenClaw's Vaultwarden integration:

# Get password from vault cache
PASSWORD=$(.secrets/get-secret.sh "VPS - Eva")

# Use in ansible (not recommended - use ansible-vault instead)
ansible-playbook site.yml -e "ansible_ssh_pass=$PASSWORD"

Better: Store in Ansible Vault and use --ask-vault-pass.

References

• references/best-practices.md - Detailed best practices guide
• references/modules-cheatsheet.md - Common modules quick reference
• references/troubleshooting.md - Extended troubleshooting guide

External Resources

• Ansible Documentation
• Ansible Galaxy - Community roles
• geerlingguy roles - High quality roles
• Ansible for DevOps - Book by Jeff Geerling