A blueprint can optionally define a lease duration for machines provisioned from that blueprint.
If a blueprint does not specify a lease period, machines are provisioned from that blueprint with no expiration date. If a blueprint specifies a single value for lease duration, machines are provisioned from that blueprint with an expiration date based on the blueprint lease duration. The expiration date is calculated from the time of the request, not from when the machine is provisioned.
If a blueprint specifies a range of possible lease durations, a user can select the desired lease duration within that range when submitting the machine request. Machine requests can be subject to approval based on the requested lease duration only if you use the Always condition.
When a machine lease expires, the machine is powered off. When the archive period expires, the machine is destroyed. You can reactivate an archived machine by setting the expiration date to a date in the future to extend its lease, and powering it back on.
You can send notification emails to alert machine owners and business group managers that a machine's lease is about to expire and again when the lease expires. See Customize the Date for Email Notification for Machine Expiration and Configuring Templates for Automatic IaaS Emails.
Users can be entitled to request a lease extension at any time before it expires. A business group manager or support user can also change the expiration date for a machine after it is provisioned.