Ansible: Configure Servers Without Logging In

Ansible connects over SSH and applies tasks described in YAML. No agent is needed on the servers.

inventory.ini:

[web]
10.0.1.11
10.0.1.12

[web:vars]
ansible_user=ubuntu

site.yml:

- hosts: web
  become: true
  tasks:
    - name: Install nginx
      ansible.builtin.apt:
        name: nginx
        state: present
        update_cache: true
    - name: Start and enable nginx
      ansible.builtin.service:
        name: nginx
        state: started
        enabled: true

python3 -m pip install ansible-core==2.13.*
ansible web -i inventory.ini -m ping
ansible-playbook -i inventory.ini site.yml --check --diff
ansible-playbook -i inventory.ini site.yml

Tasks are idempotent: running again changes nothing if the server is already correct. Use --check first, keep secrets in Ansible Vault, and use fully qualified module names as shown, which newer releases expect.