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Cyber Range Pool Model


The Virginia Cyber Range is dedicated to providing our users with the best experience while using our virtual machines in the exercise area. In an attempt to reduce the amount of time it takes to access a virtual machine for the first time, the Cyber Range developed the pool model concept. By following the tips in this guide, you and your students will have your Virtual Machines ready to go at the start of your class.

What is the Pool Model?

Brand new virtual machines may take 15-20 minutes to completely warm up while their cloud storage is synced. However, after a VM has been warmed, it only takes about 45-60 seconds to startup. The Cyber Range introduced the Pool Model to help alleviate the wait time experienced when booting up a VM for the first time.

The Pool Model utilizes a separate pool of pre-warmed VMs for each individual exercise environment. The number of VMs in the pool will scale up and down daily based on how many users are expected to need VMs. This will be based on the "Reserved Enrollments" chosen by instructors as well as the number of email invitations sent from courses.

The Pool Model is particularly helpful for larger classes that use invitation codes for registration. By properly setting your Reserved Enrollments, you can ensure that there will be enough pre-warmed VMs so your students can startup their VMs with minimal delay.

Preparing for a Large Course

The best way for instructors to ensure all users in their courses can use their VMs without delay on first use is to properly set the Reserved Enrollments. This is done when initially requesting a course or you can contact support to retroactively adjust the "Reserved Enrollments" if your course has already been approved. Additionally, instructors will need to choose which exercise environments they wish to use and provision them. This will help the Pool Model adjust the available pre-warmed VMs as needed.

For example, let's say you were planning on adding 50 users via invitation code to use the Cyber Basics environment. First, you should set your "Reserved Enrollments" to 50. Then you should add the Cyber Basics environment to your course. This will signal to our Pool Model that 50 Cyber Basics environments will be needed soon and those VMs will be provisioned on the next day.

Setting Reserved Enrollments


Please make sure to set reserved enrollments approximately to the amount of students you plan on having in the course. Overestimating the number of enrollments can waste shared cloud resources. If you are not sure on the amount of students that will be in your course, we recommend setting Reserved Enrollments to 0.

Reserved Enrollments can be set in both new and existing courses. We will demonstrate how to complete this task in both cases below.

New Course

  1. Navigate to the Courses tab in the Exercise Area and click on the "Request new course creation" button (designated by a plus symbol) to create a new course. Courses is the first tab in the header navigation.
  2. In the "Create a New Course" dialog, set the Reserved enrollments to your expected number of users. Reserved enrollments field is after the Business Unit field.

Existing Course


This option is only available to Course Admins. Instructors should contact support if the Reserved Enrollment number needs to be updated on an existing course.

  1. Navigate to a course that has already been created
  2. Click on the pencil icon to "Edit this Course" Edit this Course button is the first in the set of action buttons on a course page.
  3. In the dialog box, set the Reserved Enrollments to your expected number of users Reserved Enrollments is the field after Course Description.

What if I Didn't Set Reserved Enrollments Prior to My Course?

If you are working with a smaller class (less than about 20), you should still be fine. We keep a minimum number of VMs ready in each exercise pool, so load times should still be pretty quick for your class. If you are working with a larger class and have not made any enrollment reservations, we recommend that you start provisioning VMs at least 20 minutes before they need to be used for the first time. To do so all at once, instructors can use the start all exercises feature. More information can be found in our article on the Start All Exercises Feature.

This process will not be required on subsequent startups and access to VMs should be quick. As an instructor, you can use the power button on your students' VMs to get the warming process started. Some of the VMs will be pulled from the pool, so they will provision very quickly, but some will need to wait the full ~20 minutes.

Have a Question? Contact Support

We're here to help you. If you still have questions after reviewing the information above, please feel free to submit a ticket with our support team and we'll get back to you as soon as possible.