Drivers: Docker | Nomad | HashiCorp Developer
Fleeting- External reference: https://developer.hashicorp.com/nomad/docs/drivers/docker#gc
to prevent nomad from deleting images to soon
image_delay - A time duration, as defined here, that defaults to 3m. The delay controls how long Nomad will wait between an image being unused and deleting it. If a task is received that uses the same image within the delay, the image will be reused. If an image is referenced by more than one tag, image_delay may not work correctly.
— https://developer.hashicorp.com/nomad/docs/drivers/docker#gc