Agent identity

Zincati agent tries to derive a unique identity for the machine it is running on by introspecting the underlying OS and reading user configuration. This includes assigning an ID and a group label specific to the agent, so that cluster-wide upgrades can be orchestrated via phased rollouts and lock-based reboots.

Identity configuration

All agent identity values are normally auto-detected at startup and do not require user intervention.

However, the following settings can be overridden through configuration fragments in the identity section:

The following are defaults for each setting:

  • group (group label) is set to default
  • node_uuid (agent ID) is automatically generated, by hashing /etc/machine-id content
  • rollout_wariness is unset and the Cincinnati backend will assign a dynamic value to each request

When the agent ID is not customized via configuration fragments, its default value is dynamically generated starting from /etc/machine-id content and from a Zincati specific application ID. For more details about such application-specific machine IDs, see machine-id documentation.

Example

As an example, users can specify custom identity parameters by writing a configuration fragment to /etc/lib/zincati/config.d/90-custom-identity.toml:

[identity]
group = "workers"

The fragment above will steer the node into the “workers” reboot group.