upgrading form 4.2 to 5.x

[Kevin Oberman]

> Date: Sat, 17 Jul 2004 17:14:22 -0400
> From: epilogue <epilogue at allstream.net>
> Sender: owner-freebsd-stable at freebsd.org
> 
> On Sat, 17 Jul 2004 14:50:13 +0200
> Remko Lodder <remko at elvandar.org> wrote:
> 
> > Brent Bailey wrote:
> > 
> > > Hello,
> > > My company has been asked to help with the upgrade of several Freebsd
> > > systems that are pretty old. The customer is running a file server
> > > samba also running apache running FBSD 4.2,  he wants to upgrade using
> > > cvsup & the make buildworld procedure to upgrade to 5.x. Im very
> > > familier with the make buildworld procedure however there have been
> > > significant changes between 4.2 & 5.x  so is this something that can be
> > > done without many problems ?
> 
> hello brent,
> 
> though i don't know anyone who has gone this route, i imagine it is
> possible.  the reason most people don't cvsup from 4.x to 5.x is because
> there is a fundamental change in the filesystem (details of which escape me
> now - check the release notes at freebsd.org).  by simply cvsupping, you
> will _not_ be able to take advantage of the new filesystem.
> 
> if your customer insists upon 5.x, it would probably be best to prepare a
> full back-up then:
> 
> a) take the machine down, make a fresh install of 5.x, then load back data.
> 
> b) build and configure a parallel 5.x machine, load it with the backed-up
> data, then find a new use for the 4.x series machine.

I have gone this route a couple of times. It was an interesting exercise,
but not one I would recommend. It works, but things like the transition
from ufs to ufs2 and new threading libraries and LOTS more make it a
rough way to go. I think the advise to do a fresh install is the best
option if you go to 5, but I'd really recommend staying at 4.10 or
STABLE for now.
-- 
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman at es.net			Phone: +1 510 486-8634