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endoalpha
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PostPosted: Sun Jul 28, 2002 6:47 am    Post subject: /boot linked to itself? Reply with quote

Do I have an odd setup or is there a /boot/boot dir linked to '.'? In other words, I have: in my /boot dir
amdxp boot # ll
total 1602
-rw-r--r-- 1 root root 538849 Jul 10 18:10 System.map
lrwxrwxrwx 1 root root 1 Jul 27 16:08 boot -> .
-rw-r--r-- 1 root root 1076013 Jul 10 18:10 bzImage
drwxr-xr-x 2 root root 1024 Jul 10 18:21 grub
drwx------ 2 root root 12288 Jul 10 09:12 lost+found
drwxr-xr-x 2 root root 1024 Jul 17 22:54 memtest86
amdxp boot #
If i remove that /boot/boot link, I can't boot. (file not found error).
I don't quite understand.. kind of...
Can someone enlighten me a little?
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pjp
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PostPosted: Sun Jul 28, 2002 6:51 am    Post subject: Reply with quote

That is normal, I'm not sure why.
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rac
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PostPosted: Sun Jul 28, 2002 6:57 am    Post subject: Reply with quote

kanuslupus wrote:
That is normal, I'm not sure why.

To reduce the number of "GRUB doesn't work!" posts. Having that symlink means that even if you specify an extra /boot in the kernel path when you have a separate boot partition, GRUB will still find your kernel.
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friedmud
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PostPosted: Sun Jul 28, 2002 7:06 am    Post subject: Reply with quote

I was waiting for someone other than me to notice this....

I noticed it on one of my first install trials - and I'm pretty sure I know why they do it too...

It all has to do with grub.

From the install doc:
Code:

default 0
timeout 30
splashimage=(hd0,0)/boot/grub/splash.xpm.gz

title=My example Gentoo Linux
root (hd0,0)
kernel /boot/bzImage root=/dev/hda3


NOTE: this explanation assumes you did a *mostly* default install.

First of all notice that you refer to root as (hd0,0) - that is the *boot* partition. This partition is the one that is actually mounted under /boot normally - BUT... IT ITSELF DOES NOT HAVE A BOOT DIRECTORY IN IT!

So - you see how you are referring to both the splashimage and the kernel as being in /boot ?? Grub starts looking in your boot partition for a directory called "boot" - but one actually doesn't exist - so instead we make a symlink back to the root of the boot partition and name it boot - so grub will look there for bzimage.

Does that make any sense???

Now the real question here is: WHY? Well, I think the reason is that people would get confused - because most people dont think about the fact that the boot partition is the only thing grub looks at - so grub doesn't know that it is normally mounted under /boot. So the correct line (if you wanted to do it without a symlink would be:

Code:

kernel /bzImage root=/dev/hda3


But like I said this would confuse people because they would think that they need to put the kernel in the root of their filesystem (/) in order for grub to see it. So instead, to remain consistent - and so people wont ask to many questions they make a symlink.

OK - I know that was kind of convoluted - so what it comes down to is it is there to keep confusion to a minimum.

:wink:

Hope That Helps....

Derek
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pjp
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PostPosted: Sun Jul 28, 2002 7:08 am    Post subject: Reply with quote

rac wrote:
To reduce the number of "GRUB doesn't work!" posts.
:lol: If it has, I'd hate to see how many there would be if they didn't do that. Interesting to know that 'trick' though.
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endoalpha
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PostPosted: Sun Jul 28, 2002 7:46 am    Post subject: Reply with quote

friedmud and rac:

You are right on... When I rm the /boot/boot link, I had to cmdline grub to boot /bzImage... NOT /boot/bzImage..
I noticed this quite a while ago too, but never gave it much thought until i decided to delete /boot/boot, then I had to give it some quiet contemplation....
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mksoft
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PostPosted: Sun Jul 28, 2002 9:00 pm    Post subject: Reply with quote

That depends if you have /boot as a sepreate partition or not.

If yes, the kernel won't be in /boot/bzImage since there's not /boot dir on the /boot partition (for sake of argument /dev/hda), only on the root partition.

If not, the kernel will be in /boot/bzImage, since /boot is a directory on the root partition grub refers to.

If /boot points to itself, even if /boot is a seperate partition, the image (and stage files, menu.lst) can be found as well under /boot.

You can remove the symlink but make sure you have grub configured correctly. To prevent any confusion this solves it quite nicely (and elegant IMO).
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thor
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PostPosted: Sun Jul 28, 2002 9:22 pm    Post subject: Reply with quote

i never had this symlink, so in my first time booting gentoo, grub didn`t find the splash- and bzImage and i edited it by cmdline in grub that kind (removing /boot). after it also in menu.lst and all went fine.
so my question is, why no symlink? probably because of not making 'mkdir boot' in /mnt/gentoo at setup. i unpacked the tarball and then mounted boot in now existing boot folder.
can you agree with this?

hde1=boot - hde2=/ - hde3=opt - hdg1=swap - hdg2=/home

sorry for my bad english :roll:

th.
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abhishek
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PostPosted: Mon Jul 29, 2002 6:41 am    Post subject: Reply with quote

thor wrote:
i never had this symlink, so in my first time booting gentoo, grub didn`t find the splash- and bzImage and i edited it by cmdline in grub that kind (removing /boot). after it also in menu.lst and all went fine.
so my question is, why no symlink? probably because of not making 'mkdir boot' in /mnt/gentoo at setup. i unpacked the tarball and then mounted boot in now existing boot folder.
can you agree with this?

hde1=boot - hde2=/ - hde3=opt - hdg1=swap - hdg2=/home

sorry for my bad english :roll:

th.

U should have mounted boot then unpacked the tarball, becuase the link is in the tarball. I formatted boot after extracting the tarball an had no link and ended up edinting menu.lst on the command line.
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