Re: [gentoo-user] Grub2 and is the upgrade a tooth puller.

[Neil Bothwick]

On Mon, 25 Jun 2012 00:05:25 -0500, Dale wrote:

> It appears that grub2 is coming soon.  Thread on -dev said a couple
> months or so till it hits the tree, keyworded and/or masked I'm sure.  I
> guess it is about time to jump off the cliff and give this a try.

If GRUB legacy is working for you, I see no need to change. I put GRUB 2
on new installs but haven't seen any reason to switch over existing
systems.

On the other hand, if you want to learn more about it, go for it!
 I
> My first question is, how hard is this to change from old grub to
> grub2?

The same as installing GRUB 2 from scratch. I would waste time trying to
have both installed (I'm not sure if that's even supported any more)
as it's easy enough to reinstall legacy from a live CD if you have to, but
keep your menu.lst.

> I must confess tho, I'm a
> hoarder of kernels.  LOL   I generally have several versions of them on
> here.  Is there a way for it to only see say the last 3 versions or so?
> I only have three right now but I cleaned out all the non-init kernels a
> while back.  Given time, I may have a dozen or so.  I would rather not
> have that many lines on the grub screen when booting.

You could edit the script that searches for an adds Linux kernels, or
disable it. I use the custom script to add my own entries at the top of
the menu and let the standard 10_linux script add all detected kernel
below. It lists them most recent first, so any excess of kernels falls
off the bottom of the screen :)

> Also, will it know what init thingy image to connect the kernels too?  I
> name my kernels with the version and name the init thingy with a similar
> name.  Looks someting like this:
>
> root@fireball / # ls -al /boot/bzImage-3.*
> -rw-r--r-- 1 root root 4740064 May 16 20:25 /boot/bzImage-3.3.5-2
> -rw-r--r-- 1 root root 4758496 May 23 13:09 /boot/bzImage-3.4.0-1
> -rw-r--r-- 1 root root 4758816 Jun 14 09:00 /boot/bzImage-3.4.2.r1-1
> root@fireball / # ls -al /boot/initramfs-3.*
> -rw-r--r-- 1 root root 3560934 May 12 05:03 /boot/initramfs-3.3.5-1.img
> -rw-r--r-- 1 root root 3560423 May 23 13:10 /boot/initramfs-3.4.0.img
> -rw-r--r-- 1 root root 3561170 Jun 14 09:05 /boot/initramfs-3.4.2.img

That should work, although I do not use a separate initramfs file so I
haven't tried it.

> There are times when I may have more than one kernel but only one init
> thingy tho.  So far, one init thingy will work with any kernel of that
> version.  I have not tried mixing tho.

Use symlinks, or a custom menu.

> Also, how much disk space does grub take up on /boot?  Mine is on a
> separate partition and I hope it is large enough.

% df /boot
Filesystem     Type  Size  Used Avail Use% Mounted on
/dev/md0       ext2  482M  406M   51M  89% /boot

However, 380MB of that is a System Rescue CD ISO, one of the nice things
about GRUB 2 is that you can boot straight fro the ISO, no need to go
hunting for a CD when you need a live boot (unless the reaso you need a
live boot is that you screwed up GRUB :)

% du /boot/grub2
1.5M    /boot/grub2

A GRUB legacy box here gives

% du /boot/grub 
990K    /boot/grub

so not much difference.

> Miss the compile output?  Hint:
> EMERGE_DEFAULT_OPTS="--quiet-build=n"

This is redundant now, portage has gone back to the old method of
spamming your screen with compiler output when using --jobs 1.


-- 
Neil Bothwick

Home is where you hang your @.