[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Bug#485790: generate separate /boot as workaround for buggy LBA48 ?



On Friday 13 June 2008, Goswin von Brederlow wrote:
> > Earlier instances of the same problem.  The 8 GiB barrier was because
> > of the BIOS only issuing one 24-bit ATA command.  I'm not sure how
> > common will the new limit be in comparison.
>
> As well as 518MB, 2GiB, 32GiB, 64GiB, 128GiB. PC BIOSes are just
> riddled with those stupid problems.

Yep.

> >> I wonder what we should do about this:
> >> - just always create a /boot partition when guided partitioning is
> >> used
>
> There is only one reason to have a seperate /boot: / is crypted. And
> then you always need one.

And LVM when used with some/most bootloaders, and most RAID setups.

> In all other cases a small / partition is the superior solution imho.
>
> So my solution would be to default to a seperate small / partition at
> the start of the disk unless crypted is selected and then start with a
> small /boot.

That may still not solve the problem for one important class of installs 
though: dual boot systems where the size of $other_os partition + the / 
partitions exceeds what the BIOS supports.

> The risk of detection problems certainly outweighs the drawbacks of
> always having a small / or /boot.

The disadvantage of that (assuming you want to avoid LVM) is that for a 
really small / you'll need at least separate /var, /usr, /tmp, /srv 
and /home partitions and then you have the question what the best 
relative sizes are for that particular user.

Here's a wild idea that could be used to work around that.

Create two partitions: / and a partition e.g. "/media/multifs".
And then bind mount all other partitions inside the second one.

/etc/fstab would look something like this:
<snip>
# /etc/fstab: static file system information.
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
proc            /proc           proc    defaults        0       0
/dev/hda1       /               ext3    errors=remount-ro 0       1
/dev/hda3       /media/multifs  ext3    defaults        0       2
/dev/hda5       none            swap    sw              0       0
/dev/hdc        /media/cdrom0   udf,iso9660 user,noauto     0       0
/dev/fd0        /media/floppy0  auto    rw,user,noauto  0       0

/media/multifs/home	/home	ext3	bind		0	0
/media/multifs/srv	/srv	ext3	bind		0	0
/media/multifs/usr	/usr	ext3	bind		0	0
/media/multifs/var	/var	ext3	bind		0	0
/media/multifs/tmp	/tmp	ext3	bind		0	0
</snip>

I've tested this and it actually seems to work. If people like this idea, 
all we'd need is to add support for it in partman :-)
One added advantage would be short fsck times for /.

Cheers,
FJP

Attachment: signature.asc
Description: This is a digitally signed message part.


Reply to: