FC3 upgrade without booting off cd

[David Bandel]

On Thu, 11 Nov 2004 09:55:05 -0500 (EST), Net Llama!
<netllama at linux-sxs.org> wrote:
> On Thu, 11 Nov 2004, David Bandel wrote:
> >
> > Probably because during the upgrade process there's at least an hour
> > (if not more) where the services provided by the system are not
> > available.  The upgrade the original poster wants to do would allow
> > services to continue to run until the new service is installed, and
> > then a simple restart handles the problem.
> 
> Yea, but i'd have to wonder how stable or reliable the system would be
> while all of that was happening.  Hell, its upgrading stuff like glibc and
> adding udev.  Those aren't trivial changes that won't have some kind of
> impact.

Well, udev is a POS. I've had to uninstall it on every system I've
tried to use it on.  I'm either using devfs (still) or the static dev
files.

I've never had a problem upgrading glibc on a live system.  You do
have to know which services to restart (like SSH, Apache, and a few
others).  But you can do it and still be running the services.  If you
reboot to upgrade, your services are all down until after the upgrade
is complete.  In some places I've done upgrades, this is not
tolerable.  A reboot at the end is barely tolerable, but what could
amount to hours offline is not.

> 
> > This is one of the nice things about Debian upgrades.  They aren't a
> > .. OK, everything is going down for the next few hours .. deal.  Same
> > for Gentoo.  You upgrade little by little on a daily or weekly basis
> > and are always current.
> 
> Yea, but you still have to reboot for a kernel change.  And if added or
> removed udev/devfs that would be really scary trying to activate the
> change on a live system without a reboot.

How long does it take your system to reboot?  A matter of minutes, I
assume (2-3 max?).  This is a _lot different than being down for hours
(or even 30 minutes).

I run an ISP.  I can afford to reboot a system once in a while (maybe
even once a day).  But if a system goes down for even 5 minutes (much
less 30 or more to do an upgrade), the phone calls from irate
customers delay me even longer.

I don't risk downtimes longer than a reboot.  At least not
deliberately.  Uptimes are not as important to me as not having
services go down, or if they do, for _very_ short intervals.

Ciao,

David A. Bandel
-- 
Focus on the dream, not the competition.
            - Nemesis Air Racing Team motto