ansible.cfg

Goal

Stop repeating -i inventory.ini and connection flags on every command.

Project layout

On the control node:

mkdir -p ~/ansible-project
cd ~/ansible-project

inventory.ini

[web]
prod-managed-node-1 ansible_host=54.179.68.157 app_name=frontend
prod-managed-node-2 ansible_host=54.254.115.55 app_name=backend
 
[web:vars]
ansible_user=ubuntu

ansible.cfg

[defaults]
inventory = inventory.ini
host_key_checking = False
remote_user = ubuntu
private_key_file = ~/.ssh/id_ed25519
forks = 10
timeout = 30
log_path = ansible.log

Verify config is loaded

ansible --version
# look for: config file = .../ansible-project/ansible.cfg
 
ansible-inventory --list
ansible all -m ping

With ansible.cfg present:

# Before
ansible all -i inventory.ini -u ubuntu -m ping
 
# After
ansible all -m ping

Override when needed

CLI flags still win for a single run:

ansible all -i other-inventory.ini -m ping

Search order

Ansible looks for config roughly in this order (first found wins):

1. ANSIBLE_CONFIG environment variable
2. ./ansible.cfg (current directory)
3. ~/.ansible.cfg
4. /etc/ansible/ansible.cfg

Student tasks

1. Create ~/ansible-project with inventory.ini + ansible.cfg
2. Confirm ansible --version shows your config file
3. Ping all hosts without -i
4. Change forks and re-check with ansible-config dump
5. Generate a sample config: ansible-config init --disabled > sample.cfg

Interview reminders

• What is ansible.cfg? Project/user/system defaults for inventory, SSH, parallelism, and more.
• Which config wins? The first found in the search order (or ANSIBLE_CONFIG).
• Best practice? Keep ansible.cfg in the project root and commit non-secret settings with the repo.