Images

An Image (or Cloud Server Image) is a copy of a virtual disk from which a Cloud Server can be built. Brightbox provides several official up-to-date images for common operating systems (such as Ubuntu, Centos, Fedora, FreeBSD and Windows), but you can supply your own (and share them with other users if you like).

To create your own image, you can either snapshot an existing server or upload a new image to the Image Library and register it (see Image Library Guide for a walk-though)

The Image you choose affects some aspects of the Server it is used to create.

Architecture

Each Image has an architecture attribute, either i686 (32bit) or x86_64 (64bit), which sets the architecture of your new server.

Mode

An Image can be set to one of two modes: virtio or compatibility.

An Image with the mode virtio creates servers with virtio virtual devices. virtio devices allow for higher performance but require that the operating system have proper support for them.

If your operating system does not support virtio then it will not be able to access the network or disk devices.

Most modern Linux kernels have virtio support built-in, but many other operating systems, such as FreeBSD or Microsoft Windows, do not.

compatibility mode replaces any virtio devices with emulated equivalents, which allows a broader range of operating systems to work without modification at the cost of some performance.

More information on virtio, including some details about the Windows drivers, can be found on the libvirt wiki.

Status

An Image can be in one of several states, which affects how it can be used and how it is displayed. An Image with status available can be used to build new servers. You can monitor the progress of an Image in creating state by watching the disk_size attribute.

Creating

Status creating means the Image is currently being created, either from a server being snapshotted or an uploaded Image being registered. Images in the state creating cannot be used to build new servers.

Deleted

Status deleted means the Image has been removed from the Image Library and is no longer available to build new servers.

Failed

Status failed means the Image was not successfully created - usually indicating that either a server snapshot or a registration did not succeed.

Deprecated

Status deprecated means the Image does not show up in the list, but it is still available for building new servers to those who know the identifier. This is often used in the situation where you have an image that is public and you want to release a new version of it. Removing the old version straight away will affect any users who have hard-coded your image’s identifier into their build scripts. Setting it as deprecated makes it clear it’s not supposed to be used any more, giving existing users a chance to update their systems.

Image size

An Image is stored in the Image Library in a compressed format. Basically, this means any zeroes in the Image don’t actually take up space in the Image Library.

So this means an Image has two different size attributes. The disk_size is how much actual non-zero data is in the Image.

The virtual_size is how big the Image is once uncompressed and written to your Server (so including the zeroes).

This means that the server type you choose for your server must have a disk at least as big as the virtual_size of your Image, or it will not fit.

Username

The username attribute defines the default user account that the Image is set up with. This is usually the account that gets your ssh key on first boot.

Image Access

Both uploaded images and snapshot images are private by default, which means only the account that owns them can list them or build servers from them.

If you make an image public, other Brightbox users can see them and build servers from them.

Official Images

An Image with the attribute official set to true has been provided by Brightbox. This flag is mainly just used to display these Images slightly differently to indicate they are trustworthy.