What is Images?
Learn where the images for your virtual machines come from, how you capture your own, how images relate to restore points, and how they're billed.
An image is the template for an instance's OS disk: an operating system and, for an image that you capture, your software and settings. You choose an image when you create an instance, and the instance's OS disk is created from it. Images come from the region's catalog, or you capture them from your own instances.
Key features
- Region catalog. Start from the operating system images that the region's operator publishes, some of them marked Recommended. See Boot sources.
- Your own images. Capture an instance as an image, with its operating system, software, and settings, to launch identical instances. See Capture an image from a virtual machine.
- Instances and volumes from images. Launch instances from an image, or create a bootable volume from it. See Launch virtual machines from an image.
How it works
The creation wizard lists images from two sources, and each image says where it comes from:
- Region catalogue: images that the region's operator publishes. You can use them, but you can't delete them.
- Your project: images that aren't in the region's catalog, such as the images captured in your tenant's projects.
An image can require a minimum amount of memory and a minimum disk size. The wizard applies both when you choose a size and the OS disk. An image from the catalog can also carry a software license, which is billed on every instance that boots from it.
The console has no separate page for images. You see them where you use them: in the image list of the creation wizard and in the image list of the volume form. Viewing and deleting your own images are available through the API only.
Images and restore points
When you capture an instance, you choose what you get back:
| Reusable image | Restore point | |
|---|---|---|
| Purpose | Launch new instances from a prepared template. | Go back to the state of one instance. |
| Where it's listed | The image list of the creation wizard. | ComputeInstance snapshots, and the Snapshot boot source of the wizard. |
| Name | 3–63 characters: lowercase letters, numbers, dots, and hyphens. | 1–255 characters. |
Both copy every disk of the instance, and both keep those copies in the cloud as volume snapshots for as long as they exist. While they exist, the instance's volumes can't be deleted. See What is Snapshots?.
Use cases
- Golden images. Prepare an instance with your operating system settings, agents, and software, capture it, and launch every new web or application server from the image.
- Scale out. Create several identical instances from your image in one request. See Create several identical instances.
- Bootable volumes. Create a volume from an image, and boot an instance from that volume.
Billing
Images bill these dimensions:
| Dimension | How it's billed |
|---|---|
| Images that you own | As image storage, per GB-month, for as long as the image exists, when the region has a price for it. |
| Images from the region's catalog | Not billed as storage. A license that comes with an image is billed on the instances that boot from it. |
An image whose capture fails isn't billed. Every resource is billed for at least 60 seconds over its lifetime, once. For how usage becomes charges on your invoice, see How billing works. For prices, see Pricing.
Limits
- You can create images from your instances, and through the API from volume snapshots. The console and the REST API don't offer an image upload or import.
- An image name has 3–63 characters, and no other image can have the same name.
- The REST API refuses to delete an image while instances that were created from it exist.
- Encryption at rest for images is available only where the region supports it; the console shows the option only there.
Related services
- Virtual Machines: instances that boot from images.
- Snapshots: restore points and volume snapshots.
- Block Storage: bootable volumes created from images.