Per-Host Variables

Per-host variables are values that differ between individual Pis — for example, each Pi might control a different door, so each needs its own door_id and user_id. In Semaphore, these are defined directly in the Ansible inventory.

Setting up the inventory

1. In Semaphore, navigate to Inventory.
2. Click New Inventory → Ansible Inventory.
3. Give it a friendly name (e.g. Rondo Hosts).
4. Select your credentials as needed.
5. Set the type to Static YAML.
6. Paste and fill in the following template:

notes:
  hosts:
    pi1:
      ansible_host: 192.168.1.101
      ansible_user: pi
      DOOR_ID: e3a1d7f9-6b3c-4f59-b813-1a728a214d89
      USER_ID: pi1_user
    pi2:
      ansible_host: 192.168.1.102
      ansible_user: pi
      DOOR_ID: e3a1d7f9-6b3c-4f59-b813-1a728a214d89
      USER_ID: pi2_user
    pi3:
      ansible_host: 192.168.1.103
      ansible_user: pi
      DOOR_ID: 7c5e8a92-2b41-4de6-8a3f-4d182bb5f2e9
      USER_ID: pi3_user

Add or remove hosts as needed. Each host entry can carry any variable you want to vary per device.

How it works

When the Ansible playbook runs, the values defined here are available as host variables. The config.yml.j2 Jinja2 template uses them to render a unique config.yml for each Pi at deploy time — so pi1 and pi2 can share a door while pi3 controls a completely different one, all from a single playbook run.