Re: Embedding a file into core.img

[Andrey Borzenkov]

В Wed, 20 Mar 2013 10:34:46 +0100
"Arbiel (gmx)" <address@hidden> пишет:

> Hi
> 
> I try to record in the MBR of USB keys an autonomous MBR (no support of 
> any other directory or file) to boot a PC with the system located on a 
> partition whose name is predefined "cielos", and in case this fails, to 
> chainload to the hd0's MBR.
> 
> I've understood from Grub's Manual that to achieve such a goal, I have 
> to embed the file using option -c of grub-mkimage.
> 
> I have now modified the --grub-mkimage option to point to the shell 
> script which creates /media/maisonnette/grub/core.img and from there I 
> have been able to imbed the file and launch a boot process. However, 
> this process failed, with a "no such device : the uuid I used in my 
> search.fs_uuid command" whereas such a device exists on my external device
> 

You need to include much more of grub modules than you did. At least
you need disk driver and filesystem driver to read UUID. 

grub-install creates exactly the same embedded config. Why do not you
simply use it?

> The imbedded file reads
> 
> search.fs_uuid 0aceef09-a694-4105-bade-2dca95a09a08 root
> set prefix=(root)/boot/grub
> 
> and a sudo blkid | grep 0aceef09-a694-4105-bade-2dca95a09a08 responds
> 
> /dev/sdb5: LABEL="cielos" UUID="0aceef09-a694-4105-bade-2dca95a09a08" 
> TYPE="ext4"
> 
> I try to understand why the search fails.
> 
> Le 20/03/2013 04:18, Andrey Borzenkov a écrit :
> > В Wed, 20 Mar 2013 00:15:07 +0100
> > "Arbiel (gmx)" <address@hidden> пишет:
> >
> >> Hi
> >>
> >> I'm trying to embed a file into core.img. I followed instructions from
> >> GNU Grub Manual's 5.4 Embedding a configuration file into Grub and tried
> >> to replicate the example given there with a config file figuring two lines
> >>
> >>        search.fs_uuid the_uuid_of_my_partition root
> >>        set prefix=($root)/boot/grub
> >>
> >>
> >> I used the following commands
> >>
> >> #! /bin/bash
> >> cd "${1}"
> >> cat 1> grub/embed.cfg <<EOF
> >> search.fs_uuid 0aceef09-a694-4105-bade-2dca95a09a08 root
> >> set prefix=($root)/boot/grub
> >> EOF
> >> sudo grub-mkimage -c 'grub/embed.cfg' -o 'grub/grub-image' -O i386-pc -d
> >> '/usr/lib/grub/i386-pc' -C none search_fs_uuid
> >
> > -O and -d together are redundant.
> >
> >> sudo chmod +x 'grub/grub-image'
> >> sudo grub-install --boot-directory=/media/maisonnette
> >> --grub-mkimage=grub/grub-image /dev/sdb 2>grub/msg.log
> >>
> >
> > --grub-mkimage points to program to create image, not to image itself.
> >
> > You do not explain what you attempt to achieve. May be using grub-rescue
> > to build ISO image that includes full grub and can optionally include
> > arbitrary files would be easier?
> >
> >> I get the following error message
> >>
> >> grub/grub-image: 1: grub/grub-image: Syntax error: word unexpected
> >> (expecting ")")
> >>
> >> Can anybody tell me what's wrong, knowing that my partition
> >> /media/maisonnette has nothing to do with the
> >> 0aceef09-a694-4105-bade-2dca95a09a08 partition.
> >>
> >> Thank you
> >>
> >> I used the following command
> >>
> >>
> >>
> >>
> >>
> >> _______________________________________________
> >> Help-grub mailing list
> >> address@hidden
> >> https://lists.gnu.org/mailman/listinfo/help-grub
> >