Grub config file editing

[Jeff Vian]

On Sun, 2006-02-19 at 16:24 +1030, Tim wrote:
> Jeff Vian:
> >>> It does not "remember" your previous selection.  It does *always* boot
> >>> the kernel marked as default unless you make some other selection from
> >>> the menu.
> 
> Tim:
> >> It is possible to configure GRUB to work the way you argue against.
> >> That can be useful for people with multi-boot systems who want to be
> >> able simply reboot the current OS.
>  
> 
> Jeff Vian:
> > OK, so you *CAN* make it do that.
> 
> Well, you were rather directly, very assertively, and not totally
> correctly, disputing a prior poster:

Point taken. Even though the setting to use the "saved" kernel has to be
manually configured it does exist.  I was basing my statement on what I
knew to that point.

> 
> John Summerfied
> >>>> However, it does not write[1] to those filesystems, and I think that 
> >>>> fairly sensible.
> >>>>
> >>>> [1] grub does write something to disk somewhere, it's able to "remember" 
> >>>> what your previous selection was, and it's able to mark a partition 
> >>>> active (for the DOS family of operating systems).
> 
> He correctly said it was *able* to do so, you said it couldn't do so
> (i.e. it doesn't remember, and it always boots the default kernel).
> 
> If you'd said it doesn't normally do that, I'd have agreed with you, but
> your prior reply was rather misleading.  Anybody who might have wanted
> to do what I'd described, might well have took what you said at face
> value, and not looked any further to see if it could have been done.
> 
I always appreciate an opportunity to learn, especially when it may aid
me in the future.  Another case where an absolute statement must be
backed by facts (that I was missing).

> > It certainly is not the default behavior and requires modification of
> > every stanza in grub.conf to achieve what you describe as well as
> > changing the default line.  That is not easy for most, nor intuitive
> > at all, and most would not consider making those changes without a
> > tutorial or a clearly documented procedure and reason.
> 
> It's not difficult to do.  And unless you never prune out all your prior
> kernels (which is bad management), it's not a lot of work.  The manual
> isn't too bad describing this, and I certainly would read a manual for
> something if I was considering customising my PC to do something.  And I
> do think it *is* intuitive that a reboot actually reboots your PC using
> the same system that you were already using, in certain circumstances
> (e.g. multiboot systems, or systems used by other people - where they'd
> expect a reboot to allow them to carry on doing what they were doing
> before, and not have to worry about anything special that you might have
> done before they started using the PC).
> 
Not at all difficult if you make that change as soon as you install the
system.  Each kernel update copies the appropriate lines into the stanza
for the new kernel so it is painless after the change has been made. 

It is intuitive that the boot should do that.  The configuration to make
it happen is what I said was not.

> > I wonder how many people on this list actually knew that was possible
> > before you posted the procedure here?
> 
> Not sure you really want an answer to that on a list which may well have
> a huge number of participants...
> 
Probably not  :-)