An image defines what will run on a guest instance with your
Eucalyptus cloud. Typically, an image contains one of the Linux
distributions like CentOS, Fedora, Ubuntu, Debian or others. It
could also contain one of the supported Windows server versions. The
format for these is identical.
Normally when we use the term "image" we mean the root file system.
Once bundled, uploaded, and registered with Eucalyptus, such an
image is known as a Eucalyptus machine image (EMI).
There are, however, other types of images that support the EMI. They
are the kernel (EKI) and ramdisk (ERI). They contain kernel modules
necessary for proper functioning of the image. Often, one set of
these ERIs and EKIs are used by multiple EMIs. Once loaded into the
Eucalyptus cloud, the EKI and ERI are referred to by the image and
you don't have much interaction with them directly.
When you run an image, you can override the image's
associated kernel and ramdisk if necessary (for example, if you want
to try out another kernel. For more information, see Associate a Kernel and Ramdisk
To help get you started, Eucalyptus provides pre-packaged virtual
machines that are ready to run in your cloud. You can get them at
the Eucalyptus Machine Images
Eucalyptus image from this site comes bundled with a correspoding
EKI and ERI. You can manually download these images from the web
page, or you can use the Eualyptus Image Store commands to list and
describe these images, as well as to install an image in your cloud.
For more information see the Eucalyptus Image Store section in the
Command Line Reference
If you find that the pre-packaged images don't meet your needs, you
can add an image from an existing, non-registered image, or create
your own image.
Once you've selected and downloaded the image(s) you plan to use,
read the details in the following section for directions about how
to bundle, upload and register the images with your Eucalyptus
To view the status of your newly created and registered EKI, ERI, and
EMI images, use the euca-describe-images command.
You can also view image status using the Eucalyptus Administrator
Console's Images page.
Once you have added your image to Eucalyptus, see the User Guide
about launching and using instances based on the image.