On 22 Mar 2013, at 23:05, Paul D. DeRocco wrote: > I'm trying to get a core-image-base-cedartrail-nopvr image to boot from an > eUSB SSD on an Intel Atom mobo. I'm following the instructions in > > <https://www.yoctoproject.org/download/intel-atom-n2600n2800d2550-wnm10-chip > set-cedar-trail> > > which tell me to dd the .hddimg file onto the flash drive. But apparently, > the image isn't an image of a regular bootable system drive, but is a "live > image" of a smaller system that can either boot the real system from a > virtualized file system in RAM whose image is read from a single file in the > first level, or it can install the real system to a different drive. > (Correct me if I'm mistaken about any of this.) > > What's the point of all this? It seems like a completely unnecessary layer > of complexity and inefficiency. I have a very vague understanding of the > whole concept of running a live image off a virtual file system, and it > seems to make sense when you're booting off a readonly medium like a DVD, > but this is a writable flash drive. Why doesn't the .hddimg file just > contain the real target root file system partition in it? Or is that what > some of those other files in the build/tmp/deploy/images directory > represent? If the latter, is there a way I can just directly create the > flash drive the way it will ultimately be used in the final system, without > using this "live image" stuff? > > I'd really like to be able to create the flash, mount it under Ubuntu, and > not see the five files the implement the live image, but see the full root > file system of my target.
Have a look at meta/recipes-core/initrdscripts/files/init-install.sh. This shows how the 'install' boot option of the 'live usb image' gives exactly what you want. It basically: 1) Partitions the eUSB; 2) Copies the root filesystem (one of you five files) to the eUSB (given the caveats I mentioned in my last message); 3) Installs and configures grub to boot this. The live image is a quick way to get a system up and running. It allows someone to 'try stuff' and still get back to a working system if they make an error. It's 'install' option allows you to install to a target in a more conventional way - i.e. with all the files/directories you are expecting to see. I use the live usb image to install my images to target hardware. I've modified the script so I can also use it to install to a sequence of eUSB drives that I plug into an external adaptor when I need to program a load for a production run. Chris Tapp [email protected] www.keylevel.com _______________________________________________ yocto mailing list [email protected] https://lists.yoctoproject.org/listinfo/yocto
