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Next you would need to select what your machine should boot from, and where it should store its files.There are a wide range of pre-made images available, containing a wide range of operating systems. To use one of these, select "Image" as the boot source.
It is Usually we recommended to not create a new volume but rather use the disk provided to the machine when a flavor is selected, as the disk associated with the flavor is not counted towards your storage-quota. Selecting yes when creating an image will result in the disk-size being taken from your storage qouta.
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