Questions about a /boot partition

ezor · 03-25-2006, 01:00 AM

While Googling, I saw a suggestion to create a /boot partition. I'm assuming it would be a partition in addition to Linux Swap and Linux.

What would its purpose be, (1) in a linux only or (2) in a dual boot installation?

How is this done, and where would it fit into the partitioning scheme, eg. hda1 for /boot, hda2 for Linux Swap, hda3 for Linux?

What would be the size of this partition, and what would be written into it?

Thanks for any help.

jerryvb · 03-25-2006, 01:16 AM

You can create one if you want to, but as far as I know, it's not needed for today's Linux distributions.

It used to be that lilo couldn't read the boot files past the 1024th sector on the hard drive, so a boot partition at the front of the drive was needed to house the boot files. Lilo has since overcome that limitation, so a boot partition isn't needed any longer.

jschiwal · 03-25-2006, 02:00 AM

If you have a multiboot setup where you are running more than one distro, you might have a shared /boot partition.
You would want to update the boot loader using the same distro each time, but a /boot partition <100MB could contain all of the kernel and initrd files no problem.

Another reason to have a separate /boot partition is to use a filesystem that is better supported by Lilo or Grub. For example, the other partitions may be a raid1+0 partitions, and having the /boot on an ext3 partition is easier to boot from and setup.

J.W. · 03-25-2006, 02:20 PM

One reason creating a separate /boot partition is security -- in fstab, you can mount it read-only, thus creating another barrier against anyone/anything that tries to mess with it

jomen · 03-25-2006, 03:19 PM

an ext3 partition is probably not the best choice for a /boot partition - since it is small (all you store there is a few kernels and grub's files...) and seldom written to the simplest is the best - ext2 .
A filesystem check - should it be needed - on such a small partition (mine is 32 MB) takes less than a second.
Anything else would be wasted space for a journal you never really need - goes for reiserfs as well.

ezor · 03-25-2006, 11:32 PM

I was looking for partitioning info when I came across the reference to /boot. As J.W said, it had to do with security. I gather then that it is not generally used.

Thanks everyone for responding.