Re: completely stand-alone grub (legacy or new) boot floppy - how?

[adrian15]

Stephen Liu wrote:
> Hi adrian15,
>
> FC5_64
> ======
>
>
> > If you only want a grub floppy and you don't want to make it. Try
> > Super 
> > Grub Disk ( http://adrian15.raulete.net/grub/ ). When dded to a
> > floppy 
> > and booted just press letter "c" to have a console.
>
>
> Whether after PC boots up the floppy just pressing "c" to start a
> console.  Then what will be next steps.  Would it be similar to
> starting grub, the bootloader, during booting HD?
No and yes. When the floppy boots you're presented a menu. And I suppose 
that when you boot your pc you also have a menu but different to the SGD 
ones.

If no menu.lst is found in your /boot/grub folder or if it has not boot 
entries... grub goes to the console... so if when you boot your see:
grub>

Pressing "c" after seeing the SGD main menu would be equivalent to your 
boot.

And I will say you one more thing: (Only if this feature is included in 
SGD floppy. I am sure it is included in SGD cdrom but I am not sure if 
it is included on SGD floppy )

The option is: Special Boot -- Boot your OS (linux or other one) again --

If you activate this option SGD will search for the first 
/boot/grub/menu.lst that it will find in your computer and load YOUR menu.

So that if Grub does not work... SGD can bring up your menu.


> > How to build your own Grub floppy.
> >
> > Take a floppy disk (fat or ext2)
> > Delete its contents
> > Create /boot/
> > Create /boot/grub/
> > Copy from your pc /boot/grub/* to the floppy
>
>
> following is the content of;
> # ls -al /boot/grub/
> total 207
> drwxr-xr-x 2 root root   1024 Apr 21 15:53 .
> drwxr-xr-x 4 root root   1024 Apr 21 15:53 ..
> -rw-r--r-- 1 root root     63 Apr 20 15:15 device.map
> -rw-r--r-- 1 root root   7456 Apr 20 15:15 e2fs_stage1_5
> -rw-r--r-- 1 root root   7328 Apr 20 15:15 fat_stage1_5
> -rw-r--r-- 1 root root   6592 Apr 20 15:15 ffs_stage1_5
> -rw------- 1 root root    746 Apr 28 01:02 grub.conf
> -rw-r--r-- 1 root root   6592 Apr 20 15:15 iso9660_stage1_5
> -rw-r--r-- 1 root root   8032 Apr 20 15:15 jfs_stage1_5
> lrwxrwxrwx 1 root root     11 Apr 20 15:15 menu.lst -> ./grub.conf
> -rw-r--r-- 1 root root   6752 Apr 20 15:15 minix_stage1_5
> -rw-r--r-- 1 root root   9056 Apr 20 15:15 reiserfs_stage1_5
> -rw-r--r-- 1 root root   7028 Mar  1 12:41 splash.xpm.gz
> -rw-r--r-- 1 root root    512 Apr 20 15:15 stage1
> -rw-r--r-- 1 root root 102332 Apr 20 15:15 stage2
> -rw-r--r-- 1 root root   6944 Apr 20 15:15 ufs2_stage1_5
> -rw-r--r-- 1 root root   6144 Apr 20 15:15 vstafs_stage1_5
> -rw-r--r-- 1 root root   8768 Apr 20 15:15 xfs_stage1_5
> * * * END * * *
>
> Whether copy all files to /boot/grub/ on the floppy?
If the floppy is only for grub and you do not want more to do with it... 
you can copy all of the files because they don't make any problem. They 
don't ocuppy too much space and can serve as a backup. You know although 
usually floppies are vfat... your partition might be reiserfs or ext2.

If size matters...
However if your floppy is vfat (fat or fat32) you can leave only: 
fat_stage1_5, menu.lst (optional), splash.xpm.gz (optional) stage1 and 
stage2.

If your floppy is ext2 you should change fat_stage1_5 and put e2fs_stage1_5.


> Following is the content of;
> # cat /boot/grub/device.map
> # this device map was generated by anaconda
> (hd0)     /dev/sda
> * * * END * * *
>
> Shall I delete "(hd0)     /dev/sda" 
> and add;
> (fd0)   /dev/fd0
>
> In my case "dev/fd0" is the floppy drive.
You do have to add the fd0 line.
What it is optional is removing the hd0 line. I would not remove it so 
that in a future from inside a grub shell you can do things to your hard 
disk.
> > Run grub from a linux shell.
> > Type the following commands:
> > root (fd0)
> > setup (fd0)
> > quit
>
> I suppose doing it on console (Konsole if on KDE) after "su -".  To run
> grub just type;

> # grub [Enter]
>
> > root (fd0) [Enter]
> > setup (fd0) [Enter]
> > quit
You're right. You must be root so that you can issue these commands.
And these are the right commands.
> If I'm wrong please correct me.  Tks.
>
> I suppose no change will be made on the HD.  I still don't have a clear
> picture how can the OS (FC5_64 in my case) on HD be started after
> booting up the floppy.

If you do your own floppy you can add your menu.lst (the one from hard 
disk) to  /boot/grub/ folder from the floppy. When booting the floppy 
YOUR menu will be shown but the menu.lst shown will be the one on the 
floppy NOT the one in your PC.

Usually when menu.lst is not found when booting means that the kernel 
might not be found... so I find it quite unuseful to make a floppy for 
having your own menu but... well... it depends on the situation... it 
can help you.

What I want to say is that the option:
Special Boot -- Boot your OS (linux or other one) again
from SGD would do the job in the most of the cases.

adrian15