The Blender Foundation's Flamenco render manager has just received an update that adds several features to give you more control over the workers.
Sybren A. Stüvel writes:
Today, a new version of Flamenco Manager and Worker (both versions 2.1.0) introduces more control over your Workers from the Flamenco Manager dashboard. You can now send Workers to sleep, wake them up when needed, or shut them down, all from the dashboard.