/boot partition needed?

Seiken · 04-18-2005, 09:10 AM

Here's the scenario: I have a spare PC at work for learning more about Linux. It's got a 20 GB hard drive that is currently split up with 3 GB FAT32 for XP, 3 GB FAT32 for storage, 256 MB swap, 4 GB ReiserFS for Slackware 10.1, 4 GB ReiserFS for Ubuntu 5.04, 4 GB ReiserFS for Gentoo 2005.0, and 1.6 GB unused.

Is it recommended to have a seperate /boot partition? The reason I ask is because after I installed Gentoo (it was the last one to go on), Ubuntu will no longer boot. It gets a Kernel panic error. Before I put Gentoo on, Ubuntu booted just fine. Basically, Ubuntu is the only OS to not boot now.

If a seperate /boot partition IS recommended... how big should it be, and how do I go about setting up my system so that each distro's /boot directory is located on that 1 partition. Do I have to worry about each distro overwriting files on that paritition that another distro is reliant on?

Thanks,
Seiken

Harmaa Kettu · 04-18-2005, 12:18 PM

Your problem isn't related to partitioning. The Ubuntu kernel probably needs some parameter (initrd?) that is missing from Gentoo's lilo/grub configuration.

Separate boot partition is needed only in some old 486/pentium computers if you have bigger hard disk than the BIOS supports. Otherwise it is a bad idea...

Quote:

Do I have to worry about each distro overwriting files on that paritition that another distro is reliant on?

...because exactly this happens if both distros have similarly named kernel files or if the another distro formats the partition during installation.

phen111 · 04-18-2005, 12:22 PM

Hi!

having a extra partition for the /boot directory is recommended, because the kernel has to be in the first 1024 cylinders. Otherwise the bootloader would not be able to start the linux system. Therefore, the size of the boot partition is limited by the size of each cylinder. partitioning software shows you, where the partition is lying on the disk, just take a look there.

i think (never done it before) that a single boot partition for multiple distro is ok, as long as you keep the different kernels in different directories. well it is worth a try :-)

cheers,
kai

Shade · 04-18-2005, 01:23 PM

Kai, that is an old limitation, no longer relevant to most modern systems.

--Shade

Seiken · 04-18-2005, 01:28 PM

Quote:

Originally posted by Harmaa Kettu
Your problem isn't related to partitioning. The Ubuntu kernel probably needs some parameter (initrd?) that is missing from Gentoo's lilo/grub configuration.

Separate boot partition is needed only in some old 486/pentium computers if you have bigger hard disk than the BIOS supports. Otherwise it is a bad idea...

...because exactly this happens if both distros have similarly named kernel files or if the another distro formats the partition during installation.

Thanks very much. I'll have to research Ubuntu a bit.

EDIT: In the meantime, here is my lilo.conf (from Slackware) in case anyone is able to spot what I am doing wrong:

Code:

boot = /dev/hda
message = /boot/boot_message.txt
prompt
timeout = 100
change-rules
  reset
vga = normal

image = /boot/vmlinuz
  root = /dev/hda7
  label = Slackware
  read-only

image = /mnt/ubuntu/vmlinuz
  root = /dev/hda8
  label = Ubuntu
  read-only

image = /mnt/gentoo/boot/vmlinuz
  root = /dev/hda9
  label = Gentoo
  read-only

other = /dev/hda1
  label = Windows
  table = /dev/hda

On the Ubuntu partition, Ubuntu created a symlink in "/" called "vmlinuz" that links to the actual kernel in /boot. Gentoo did not have any symlink at all for the kernel, so I just created one in /boot the same way Slackware does. When running /sbin/lilo, I get no errors or warnings.