Few Questions Regarding Partitions

[Glass Casket]

I'm following the Gentoo handbook very closely. It's not that it's not well written or that I don't understand. It's that I have question before goign any further before I delete important Kubuntu files by accident.

Here is the hardrive I will be installing Gentoo, and it also contains Kubuntu.

Disk /dev/sdb: 250.0 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1   *           1        8510    68356543+  83  Linux (66GB)
/dev/sdb2            8511       18358    79104060    5  Extended (72GB)
/dev/sdb3           18359       18995     5116702+  83  Linux (5GB)
/dev/sdb4           18996       20270    10241437+  83  Linux (10GB)
/dev/sdb5            8511       18236    78124063+  83  Linux (76GB)
/dev/sdb6           18237       18358      979933+  82  Linux swap / Solaris (1GB)

I was wondering if it were possible to use /dev/sdb1 as the boot partition for gentoo and the same swap partition. And if so, would I just mount the /boot files from the CD into sdb1 and instead o creating a new swap space, simply tell Gentoo where it is?

So I could possibly do:

# mount /dev/sdb3 /mnt/gentoo
# mkdir /mnt/gentoo/boot
# mount /dev/sdb1 /mnt/gentoo/boot

Thanks.

[spencerf]

your swap partition can be the same for both gentoo and your other linux distribution.

I'm not sure about your boot question.

what other partition is kubuntu installed in?

just don't mess around with those at all.

Gentoo in its simplest sense requires.
1. swap ---you already have this
2. root partitition ---you need to choose this
3. optionally a /boot partition. This should only be about 256Mb according to handbook.

[Cabhan]

You say that /dev/sdb1 is your boot, and that it's 66 GB. That is ENORMOUS: you don't need anything near that much. I think mine is 500 MB, and even that's bigger than most.

Yes, you can share a /boot, if you wish. The thing to beware of is that, if you compile a new kernel, it will bump the 'vmlinuz' file around. So for example, if Kubuntu is right now booting from vmlinuz, and you compile a new Gentoo kernel, Kubuntu's image will be vmlinuz.old, and booting can get really freaky.

Also, a note, you say that you're gonna mount /dev/sdb3 as your /. That's a bad idea: because Gentoo is very compile-heavy, you will need a LOT more than just 5 GB if you want to install very much at all.

[Glass Casket]

Thanks for the replies guys!

I know 66GB is really big for a boot partition. I screwed up while doing it.

But can I have two /boot partitions? One for Kubuntu and one for Gentoo? Will GRUB reconize that?

And i'll make a partition of 30GB also as /dev/sdb3 to put Gentoo on.

[Cabhan]

Yes, you can. GRUB, as I recall, reads them as partition numbers (you don't say /boot, you say hd(1,4), as I recall), so it shouldn't have a problem.

And as for which one will be used, that's determined by /etc/fstab, so you'll have no problems there either.

I also remind you that a /boot partition isn't actually necessary, it's just a security measure. You can just as easily not have a separate partition.

[gloomy]

Yes, harddisks count from zero to X likewise partitions.

Given that the boot partition is not generally large, I would also keep separate /boot partitions for separate distributions. Nothing wrong with a single boot partition though.

And I don't know where you guys picked up 256-500mb sized /boot partitions; how many kernels are you actually using? I have six on 128mb and still plenty of room left. Well, if one keeps some kind backups on /boot, may then even 1gb might be appropriate.