Re: Aptitude/Grub Problem -- Is this a bug?

[Hal Vaughan <hal@thresholddigital.com>]

On Saturday 25 February 2006 06:26, Andrei Popescu wrote:
> On Fri, 24 Feb 2006 17:19:19 -0500
> Hal Vaughan <hal@thresholddigital.com> wrote:
>
> [snip]
>
> > Okay.  That's easy and makes sense.  But there is still a problem,
> > but may be more with grub.  I went through the man pages of grub
> > and did a lot of research to figure out how to make the changes I
> > needed.  Not once did I see this documented.  So there is basically
> > a default behavior to overwrite the file, but any documentation on
> > how to prevent changes from being overwritten is obscure.  This one
> > incident has really led me to question the overall stability of
> > Stable and wonder when another muck-up like this will happen
> > because all the documentation warning about such a default behavior
> > is obscure.
>
> update-grub is run on *every* kernel install/removal/upgrade and it
> has to. If you customize your menu.lst the file itself contains the
> indications on how to do this in order to keep the changes across
> updates. It has ways of specifying kernel options for all version or
> just for one subversion, which alternates to include for each kernel
> ...

Thank you.  That is quite helpful.  I just installed a new system last 
night, and tested this by putting extra arguments in menu.lst, THEN 
doing "aptitude update && aptitude upgrade."  The result was an 
overwritten menu.lst, automatically.  So my experience confirms what 
you've said.  This is an automatic part of a kernel update.

> I do agree this can not be considered proper documented, but then
> again, update-grub is Debian specific and any grub docs don't know
> anything about it. I can't think of a better way to document this. 


That is my opinion.  So maybe it's not aptitude's problem.  And your 
point that it is NOT properly documented is my issue.  Yes, there are 
comments in menu.lst about the automagic kernel list, and yes, there 
are comments in update-grub's man page.  However, if you're making one 
change to the kernel options, there is often no reason to read those.  
For example, I needed to add "ide-reverse" to the kernel options.  I 
had found that from a lot of hard research.  The post I found it in did 
NOT include any comments about this problem.  The author may not have 
used Debian, or may not have been aware of this problem, and may 
eventually have been nailed by it, just as I was.  I had no reason, in 
that careful research to read the man page for update-grub and, even 
more, was totally unaware of its existence.  There was no obvious place 
telling me about it.

> If 
> you file a bug I think it should be against whatever package contains
> update-grub. It probably should have a BIG warning that it is
> changing menu.lst, or at least make a back-up of the old file. The
> later would be trivial to implement.

That is my thinking ,exactly.  It should be rather trival to include 
some print or printf statements and wait for the user to press "enter", 
or to even go so far as to let them pick choices of continue, abort, or 
backup the original.  Update-grub is a Bash script, so it would not be 
easy to do this, but it would be really nice if it could read the 
kernel options in the automagic kernels and if there are some options 
that are used for every kernel, include them in the rebuild.

The problem is that the default behavior can bring down a system and 
there is no warning of it anywhere beforehand.

Thanks for the extra insight.

Hal