Open Embedded Linux Entertainment Center (OpenELEC) is a small Linux distribution built from scratch as a platform to turn your computer into an XBMC media center. OpenELEC is designed to make your system boot fast, and the install is so easy that anyone can turn a blank PC into a media machine in less than 15 minutes.
This is a great live image for getting up and running with XBMC, or testing it before committing to installing to a harddisk. I've set it up today to boot from the network to see how well it works on a machine I'm thinking about using for a media centre. It was a bit of a pain to get it working, but now that it is, it works fine.
First of all, download a copy of OpenElec from http://www.openelec.tv/get-openelec/download - I got a the tarballed version entitled OpenELEC-Generic.x86_64-devel-20131026131436-r16293 from the developer sources, but I think stable versions will equally well.
This was copied to my NAS server, and untarred using the command.
tar -xvf OpenELEC-Generic.x86_64-devel-20131026131436-r16293.tar
This then spat out what I presume to be an OpenElec live-cd or some such (but who cares - we don't do CD's do we? :) ). Within the created folder, there is a 'target' folder, which contains the images you need to boot from.
Make sure the target folder is in a location where it is accessible from both HTTP and NFS. Note, I've not been able to make this boot using HTTP, and I'm not sure its possible, because it seems to use NFS as a persistent storage location for your configuration.
Next, create a folder for storing your persistent information (I created a folder called persistent within my target folder.
Now update your iPXE menu.
:OpenElec
echo Booting OpenElec Media Centre
echo HTTP and NAS Method
kernel http://boot.server/openelec/OpenELEC-Generic.x86_64-devel-20131026131436-r16293/target/KERNEL boot=NFS=10.222.222.50:/boot.server/openelec/OpenELEC-Generic.x86_64-devel-20131026131436-r16293/target/ disk=NFS=10.222.222.50:/boot.server/openelec/persistent/ netboot=nfs ssh ip=dhcp
boot
So this loads the kernel using http from the server, and passes the boot partition nfs and persistent nfs location. Note, neither of the latter two define the files, just the folder paths. The Kernel knows what its looking for when it boots.
The final variables tell the kernel that it is being booted with nfs required, to enable ssh (if you want it) and to get the IP using DHCP. There are a number of other modes for debugging, text only mode, that sort of thing, but that is not discussed here.
Anyway, other than configuring the iPXE menu to call :OpenElec, that's all there is too it.
