Grub overview/tutorial available

Grub overview/tutorial available

[Simon Kitching]

Hi All,

Just FYI, I've written up what I've learned about Grub during the last
few weeks and put it up here:

http://people.apache.org/~skitching/MineOfInformation/linux/Booting_Linux_on_x86_with_Grub2.html

This is more detailed than simple "user level", but doesn't get into any
code details. More at the "advanced sysadmin" level perhaps.

Any feedback/corrections welcome; I'm fairly new to Grub so probably
have some mistakes in there.

Regards,
Simon

Re: Grub overview/tutorial available

[Seth Goldberg]

Quoting Simon Kitching, who wrote the following on Sat, 17 Apr 2010:

> Hi All,
>
> Just FYI, I've written up what I've learned about Grub during the last
> few weeks and put it up here:
>
> http://people.apache.org/~skitching/MineOfInformation/linux/Booting_Linux_on_x86_with_Grub2.html
>

  This is excellent -- thanks for writing this up.  One difference with the 
current code, though.  The partition naming has been changed from (hdX,Y) to 
(hdX,<partitiontype>Y[,...]) (i.e. (hd0,msdos1) for the first partition 
specified by the "dos" partition table on the first disk; 
(hd0,msdos1,sunpc1) means slice 0 on the Solaris partition defined by the 
first "dos" partition on the first drive).

  Thanks,
   --S

Re: Grub overview/tutorial available

[J. Bakshi]

On Sat, 17 Apr 2010 17:39:48 +1200
Simon Kitching <simon.kitching@xnet.co.nz> wrote:

> Hi All,
> 
> Just FYI, I've written up what I've learned about Grub during the last
> few weeks and put it up here:
> 
> http://people.apache.org/~skitching/MineOfInformation/linux/Booting_Linux_on_x86_with_Grub2.html
> 
> This is more detailed than simple "user level", but doesn't get into
> any code details. More at the "advanced sysadmin" level perhaps.
> 
> Any feedback/corrections welcome; I'm fairly new to Grub so probably
> have some mistakes in there.
> 
> Regards,
> Simon

Hello Simon,

nice piece of work. thanks for the article. It would be nice if you stress on gfxterm too. It is the area where we still lacking relevant information. just my thought.

thanks

Re: Grub overview/tutorial available

[Vladimir 'φ-coder/phcoder' Serbinenko]

[-- Attachment #1: Type: text/plain, Size: 1912 bytes --]

Simon Kitching wrote:
> Hi All,
>
> Just FYI, I've written up what I've learned about Grub during the last
> few weeks and put it up here:
>
> http://people.apache.org/~skitching/MineOfInformation/linux/Booting_Linux_on_x86_with_Grub2.html
>
> This is more detailed than simple "user level", but doesn't get into any
> code details. More at the "advanced sysadmin" level perhaps.
>
> Any feedback/corrections welcome; I'm fairly new to Grub so probably
> have some mistakes in there.
>   
"This tool(grub-emu) can be used to install Grub." <--- wrong (outdated)
" Note also that there are a few commands that can be run in the “grub
shell” that are not available in a real Grub environment (because they
would be pointless)," <--- likewise
insmod /boot/grub/normal.mod normal <-- only one of 2 arguments and it
won't set prefix resulting in further problems. Correct action is:

set prefix=(<disk>)/boot/grub
insmod normal
normal

'Grub “legacy” (the 0.x series) could only boot kernels that support the
“multiboot” specification.' <--- grub legacy has a linux loader too
'As Grub2 boots kernels by invoking a helper module (“linux”, “xnu”,
“bsd”), it can boot any kernel for which the appropriate helper module
has been written. Of course if a kernel supports multiboot, then writing
such a helper module is much simpler!'
Modules are NOT ''helpers'. They are separate loaders. and multiboot
needs no 'helpers'

    linux $root/mykernel root=xyz ---->  linux ($root)/mykernel root=xyz

' search –set=MYDEV – search.label mylabel MYDEV' at very least actually
try the commands you supply

> Regards,
> Simon
>
>
>
>
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> http://lists.gnu.org/mailman/listinfo/grub-devel
>
>   


-- 
Regards
Vladimir 'φ-coder/phcoder' Serbinenko



[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 293 bytes --]

Re: Grub overview/tutorial available

[Simon Kitching]

On Sat, 2010-04-17 at 17:39 +0200, Vladimir 'φ-coder/phcoder' Serbinenko
wrote:
> Simon Kitching wrote:
> > Hi All,
> >
> > Just FYI, I've written up what I've learned about Grub during the last
> > few weeks and put it up here:
> >
> > http://people.apache.org/~skitching/MineOfInformation/linux/Booting_Linux_on_x86_with_Grub2.html
> >
> > This is more detailed than simple "user level", but doesn't get into any
> > code details. More at the "advanced sysadmin" level perhaps.
> >
> > Any feedback/corrections welcome; I'm fairly new to Grub so probably
> > have some mistakes in there.
> >   
> "This tool(grub-emu) can be used to install Grub." <--- wrong (outdated)

Fixed.

> " Note also that there are a few commands that can be run in the “grub
> shell” that are not available in a real Grub environment (because they
> would be pointless)," <--- likewise

Fixed.

I wrote this because in the command list documentation
(http://grub.enbug.org/CommandList), there is reference to a "loopback"
command as a replacement for grub legacy 'device' command, and I can't
see what use that would have in a real grub boot enviroment.

But as I'm not really sure about this, I'll just delete this section.

> insmod /boot/grub/normal.mod normal <-- only one of 2 arguments and it
> won't set prefix resulting in further problems. Correct action is:
> 
> set prefix=(<disk>)/boot/grub
> insmod normal
> normal
> 
> 'Grub “legacy” (the 0.x series) could only boot kernels that support the
> “multiboot” specification.' <--- grub legacy has a linux loader too
> 'As Grub2 boots kernels by invoking a helper module (“linux”, “xnu”,
> “bsd”), it can boot any kernel for which the appropriate helper module
> has been written. Of course if a kernel supports multiboot, then writing
> such a helper module is much simpler!'
> Modules are NOT ''helpers'. They are separate loaders. and multiboot
> needs no 'helpers'

Fixed.

> 
>     linux $root/mykernel root=xyz ---->  linux ($root)/mykernel root=xyz
> 
> ' search –set=MYDEV – search.label mylabel MYDEV' at very least actually
> try the commands you supply

Fixed.

Grub-emu doesn't work for me, and I eventually got tired of rebooting my
(only) PC to test things. Should have tried harder though :-(.

Thanks for your comments. Thanks also to Seth...

Regards,
Simon

Re: Grub overview/tutorial available

[Vladimir 'φ-coder/phcoder' Serbinenko]

[-- Attachment #1: Type: text/plain, Size: 804 bytes --]


>
> I wrote this because in the command list documentation
> (http://grub.enbug.org/CommandList), there is reference to a "loopback"
> command as a replacement for grub legacy 'device' command, and I can't
> see what use that would have in a real grub boot enviroment.
>
>   
Retrieving files from fs image or tar(.gz) archives.
> Grub-emu doesn't work for me, and I eventually got tired of rebooting my
> (only) PC to test things. Should have tried harder though :-(.
>
>   
qemu
> Thanks for your comments. Thanks also to Seth...
>
> Regards,
> Simon
>
>
>
> _______________________________________________
> Grub-devel mailing list
> Grub-devel@gnu.org
> http://lists.gnu.org/mailman/listinfo/grub-devel
>
>   


-- 
Regards
Vladimir 'φ-coder/phcoder' Serbinenko



[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 293 bytes --]