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

Re: lilo removal in squeeze (or, "please test grub2")



On Sat, 22 May 2010 23:39:52 -0400 (EDT), William Pitcock wrote:
> 
> After some discussion about lilo on #debian-devel in IRC, it has pretty
> much been determined that kernel sizes have crossed the line past where
> lilo can reliably determine the payload size.
> 
> This bug *can* be fixed, but not without a significant rewrite of the
> way that lilo's stage2 loader code works.  Given that there is no active
> upstream and that the Debian lilo package carries many patches for bug
> fixes that are alleviated by standardizing on grub2, this seems like the
> best option for Debian.
> 
> This means that users should *test grub2 extensively* before Squeeze is
> released so that any issues can be resolved now.
> 
> As for removal, the following things need to be done:
> 
> (1) The release notes need to be updated to reflect that lilo is no
> longer a bootloader option;
> (2) The debian-installer team needs to remove the lilo-installer udeb;
> (3) The ftpmasters need to remove lilo from unstable (which will be done
> using the appropriate bug filing once the above steps are made);
> (4) Users need to test grub2 now.

First of all, forgive me for cross-posting, which is generally a no-no.
But if you can cross-post, I can cross-reply.

Second, unless you reply to debian-user, to which I am subscribed, please
CC me.  I am not subscribed to any of the other lists.

I am not a Debian package maintainer or a Debian developer.  I am just an
ordinary system administrator.  So I'm sure that my opinion will not count
for much.  But I am opposed to the removal of lilo.  Both grub-legacy and
grub-pc use sectors on the hard disk outside of the master boot record
(cylinder 0, head 0, sector 1).  In other words they use cylinder 0, head 0,
sector 2 and possibly subsequent sectors on cylinder 0 head 0.  This breaks
the design of the backup software that my employer uses.  This backup software
backs up the master boot record and all partitions; but since the extra
sectors used by grub-legacy and grub-pc are outside the master boot record
and are not part of any partition, they don't get backed up.  Consequently,
if we have a hard drive failure and restore from a backup, we have an
unbootable machine.  Lilo uses only the master boot record.  A lilo-booted
machine can be backed up and restored with our existing backup software
just fine.  Given these requirements, I wouldn't use grub-pc even if it
were bug free and well documented.  (But neither is the case!)

As for the claims that kernels are too big now, I find that hard to
believe, especially now that we have the large-memory option available.
The standard stock Debian kernel image file that I use for Squeeze,
vmlinuz-2.6.32-3-686, is currently 2234080 bytes.  Are you trying to tell
me that there's no room for a 2M kernel below the start of the EBDA?

I am able to load *both* the kernel *and* the initial RAM filesystem
below the EBDA (i.e. the large-memory option is not used) if I use
MODULES=dep instead of MODULES=most in the initial RAM filesystem
under Lenny.  I'll bet I can do it with Squeeze too.

I realize that lilo doesn't work for everyone, and I'm not suggesting
that it be the default bootloader; but to get rid of it entirely is
unacceptable.  As far as I know, it's the only bootloader that meets
all of my requirements, and I will not voluntarily give it up.

No doubt you will tell me that I am welcome to maintain it myself.
Unfortunately, I do not have the requisite skills to do so.  All I
can do is to appeal in the name of reason that it not be dropped.

Also, please excuse my ignorance, but what exactly is this
"payload size" to which you refer?  Is that the same thing as the
size of the kernel?  Or is it something else?

-- 
  .''`.     Stephen Powell    
 : :'  :
 `. `'`
   `-


Reply to: