Shutdown hours overview

• Running hours appear in your local timezone, but Ocean applies them using UTC.
• You can define running hours in 30‑minute increments.
• When running hours end, Ocean scales the cluster to zero.
• When running hours begin, Ocean brings up the minimum required nodes and resumes normal autoscaling.

Why shutdown hours are not supported for GKE shielded nodes

• The Ocean controller must be running when off-time ends.
• The controller cannot run on a node managed by Ocean during shutdown hours because Ocean scales those nodes down to zero.
• Without the controller, the Kubernetes node registration process cannot complete, and the cluster cannot restart cleanly.

How the controller behaves during shutdown hours

• At the end of off-time, Ocean launches a single node from a virtual node group without taints.
• If all virtual node groups use taints, Ocean falls back to the default virtual node group unless it is configured as template-only.
• Once a node launches and registers with Kubernetes, the controller is scheduled on that node.
• The controller reports unscheduled pods, and Ocean autoscaling continues as expected.

Shutdown hours per virtual node group