This article discusses something which the OpenELEC team provides zero support for and may even be potentially dangerous. If something goes wrong you are on your own. Proceed at your own risk.

This guide follows is given as a courtesy only for the advanced or adventurous user.

This tutorial describes how to set up a multi boot environment for Ubuntu and OpenELEC.

In the end you get a system that boots to a Grub menu with openelec selected by default (so if you do/press nothing, OpenELEC loads automatically after some seconds).

When you have more than one partition on a hdd, it is wise to carefully choose where you want each partition located. I recommend using this setup:

[Ubuntu EXT3/EXT4 partition]
[(optional)Ubuntu swap partition]
[OpenELEC EXT4 data partition]
[OpenELEC boot partition]

The reason behind this setup? The OpenELEC boot partition should never have to be resized, so placing it at the end of the hdd is a safe bet. By keeping [UNUSED SPACE] in the middle of the hdd, the Ubuntu partition and/or OpenELEC data partition can expand without affecting other partitions. If you want a third os such as Windows installed, place it on the side of the [UNUSED SPACE] that you think is least likely to be resized (for example, if you don't think Ubuntu will ever need more space, place Windows directly following Ubuntu).

Note that hdd's support a maximum of 4 primary partitions (at least under gparted), so if you want to install a third OS make sure you have a free primary partition left to use.