Install world fails, computer almost unusable

[Artem Koutchine]

>From: "Joshua Lokken" <joshua at twobirds.us>
> * Artem Koutchine <matrix at itlegion.ru> [2004-04-08 06:44]:
> > IMHO the upgrade pricedure is unstable and wrong in either case.
> > 
> > What do you think?
> 
> I don't pretend to understand *all* of the reasoning behind the
> recommended upgrade procedure.  Since I began using FreeBSD, I have
> performed somewhere around 50 system upgrades on various machines, most
> of them 4.x, and have upgraded 5.1->5.2 on four machines.  Of those
> system upgrades, two have failed, or 'not worked.'  One of them was due
> to the fact that I didn't follow the recommended procedure (admittedly,
> supplemented with list wisdom), the other, because I didn't follow the
> recommended procedure.
> 
> It just works.
> 

Actually it failed only once for me since 1996. But! I alway fill
shaky when upgrading a remote server and rebootting it. Never failed
once but i CAN SEE a case when it will fail because some utility
does not match kernel at the time of installation. The ideal upgrade
procedure must allow fall back to the previous version. So, the
ideal upgrade must install everything into a temporary storage space and
after reboot,  try to replace existing files with the new onces and if after
that boot failes after the next reboot restore the originals while keeping log.
I don't think it is as hard to implement as 5.2 locking :) 

Artem