Global Variables

Global variables apply to every host in your inventory. Use these for values that are consistent across all your Pis — things like your API endpoint, authentication key, or any shared payload values.

In Semaphore, global variables are managed through the Environment feature.

Setting up an environment

1. In Semaphore, navigate to Environment.
2. Click New Environment.
3. Give it a friendly name (e.g. Rondo Global Config).
4. Make sure you’re adding values under Extra Variables — not Survey Variables.
5. Add each variable as a key-value pair.

For example, to share an API URL and key across all hosts:

{
  "api_url": "https://api.example.com",
  "api_key": "your-api-key-here"
}

Using secrets

For sensitive values like API keys, use Semaphore’s built-in Secrets manager rather than entering them as plain-text Extra Variables. Secrets are encrypted at rest and masked in job output logs.

To use a secret as a variable:

1. Navigate to Secrets and create a new secret with your value.
2. Reference it in your Environment configuration by name.

Environment vs inventory precedence

If the same variable is defined in both an Environment and a host’s inventory entry, the inventory value takes precedence for that host. This means you can set a sensible global default in the Environment and override it per host in the inventory when needed.