Agent State

The agent keeps most of its state in memory.

However, some information is persisted to ensure that the agent can recover from a restart.

Configuration

The default state provider is a file-based provider that stores the agent's state by default in the directory /var/lib/steadybit-agent. The path can be configured via the STEADYBIT_AGENT_STATE_PATH environment variable. The helm chart is, by default, creating a statefulset with a persistent volume claim to store the agent's state.

Another option is to use Redis as a state provider. The following set of environment variables can be used to configure this.

Environment Variable	Required	Description
STEADYBIT_AGENT_IDENTIFIER	yes	The unique agent identifiert, required if redis is used. Should be stable across restarts.
STEADYBIT_AGENT_STATE_PROVIDER	yes	Needs to be set to redis
STEADYBIT_AGENT_STATE_REDIS_HOST	yes	The redis host
STEADYBIT_AGENT_STATE_REDIS_PORT	no	The redis port, defaults to 6379
STEADYBIT_AGENT_STATE_REDIS_USERNAME	no	The redis username
STEADYBIT_AGENT_STATE_REDIS_PASSWORD	no	The redis password
STEADYBIT_AGENT_STATE_REDIS_DB	no	The redis database, defaults to 0
STEADYBIT_AGENT_STATE_REDIS_SSL_ENABLED	no	Should SSL be used

Extension Registrations

The agent persists extension registrations to ensure they are not lost after a restart. Extension registrations can be maintained via the agent API, see Extension Registration.

If redis is used as the state provider, existing file-based extension registrations are ignored.

Auto discovered extensions from Kubernetes are independently registered and not persisted via the configured persistence provider. They are also not visible or manageable via the agent API.

Execution State

The agent keeps track of an experiment's current execution state. This state is persisted so that actions can be rolled back in case of an agent restart.