Re: partition layouts - separate /boot

[Hollis Blanchard]

On Apr 4, 2005, at 11:55 PM, Vernon Mauery wrote:

> Hollis Blanchard wrote:
> > I've been thinking about how to install grub2 on an Open Firmware
> > system. Here's one possibility:
> >     /boot -- Linux-native filesystem (e.g. ext3)
> >         holds kernels, initrd, etc
> >     /boot/grub -- firmware-native filesystem (on Mac HFS+, on others
> > FAT, etc)
> >         holds grub executable, grub.cfg, modules
> >
> > The grub ELF file must live on a firmware-native filesystem. When run,
> > it can find out what partition it was booted from, so that is a 
> > natural
> > place to load grub.cfg from as well (and why not modules while we're 
> > at
> > it?). Thus this is the value of the "prefix" GRUB environment 
> > variable.
>
> Putting a restraint that says /boot/grub must be a separate partition 
> doesn't sound like a good idea.  It just clutters the partition table 
> with another small partition.
>
> If all it gains us is that we know where we booted from, we still need 
> to know where /boot is.  I don't see what this gains us -- the root 
> command or prefix variable is still required.  It sounds to me that if 
> you want to have a firmware native partition type, having all of /boot 
> be that type would be preferred.

I know there is at least one version of IBM Open Firmware which has a 
4GB limit on disk reads.  Creating a separate partition is the only way 
I know of to keep a filesystem from locating blocks above that 4GB 
limit.

You're correct: if we have /boot and /boot/grub partitions, we still 
need to know where /boot is. That's the heart of my question.

Haven't my arguments about trying to use FAT for /boot convinced you 
that using a firmware-native filesystem may not always be a good idea? 
To summarize, firmware-native filesystems:
- may not be well-tested (HFS)
- may not support expected features like symlinks or file permissions 
(FAT)
- may be less reliable, e.g. no journalling (FAT)
- may not support fsck, and wouldn't you like to fix filesystem 
corruption on /boot?

-Hollis