[CentOS] Upgrading FC2 to CentOS 5.* - anyone second this? - general report

> On Wednesday, May 30, 2012 02:56:24 PM Max Pyziur wrote:
>> My hope is to upgrade; that way I don't have to change/specify partition
>> topology, and hopefully only minimally adjust the existing
>> configurations.
>
> I have tried this type of upgrade before; I have not had it go well for
> the most part.  The only way I'd try to do an FC2 to C5 upgrade is by
> incrementally upgrading up to FC4 or FC5 using install media, then boot
> the C5.8 install media with 'upgradeany'.  It may break things very badly.

Just to advise the general readership. I downloaded iso's for FC3, FC4,
FC5 DVD install discs, and their accompanying rescue CDs.

The machine under consideration is old by contemporary standards (a
PIII-1400 w/ 1.5GB RAM, and three discs, one 2TB in size generally used to
store backups.

The FC2->FC3->FC4-FC5 upgrades were done in about three hours; the time
was split between checking the integrity of the DVDs and CDs and the
upgrade. Today, I did the FC5->CentOS5.8 upgrade.

In each phase, the machine booted and functioned.

I recognized the postgresql issue you mention further in your posting;
I've been through something like that several times, so I know how to work
through it.

All-in-all, this has been easy; nothing like the FC14-FC15 DVD upgrade on
my desktop that froze that I did two weeks ago (there, I spent a very
large amount of time unraveling dependency issues and package
duplications). I hope to do other FC upgrades in the spirit of being
current, but I anticipate that it won't be as easy as the FC2 -> CentOS5.8
has been so far.

I recognize that most of the comments were from sysadmins, more involved
in managing server farms, and steeped in that knowledge/experience base.

Much thanks to thoughtful comments and cautions,

fyi,

Max Pyziur
pyz at brama.com

> I have had to do this sort of upgrade on SPARC systems running Aurora
> SPARC Linux; did a yum-based upgrade up through a few revs, and it was a
> pain.  I only did it because install media wasn't already available, and
> you had to go backrev to get booting media on my particular box (although
> the installed system worked fine once installed).  It is really something
> I would rather not do without the preupgrade logic in place, primarily
> because of non-repo or third-party repo packages that may or may not be
> around any more on a newer repo; for that matter, the Fedora package set
> in the FC2 days is likely to be larger than the C5 package set unless you
> enable third party repos at install/upgrade time, and that isn't
> guaranteed to work.
>
> This sort of discussion is in the archives several times, and I think I
> have put my particular recipe out there before.  It is recommended by the
> upstream vendor, Red Hat, to not do any major version upgrades from one
> version of EL to another.  EL4 was based from around FC3, and you are
> essentially talking about a direct upgrade from a pre-EL4 to EL5; these
> two are more different than you might think. (see
> https://en.wikipedia.org/wiki/Red_Hat_Enterprise_Linux#Relationship_to_free_and_community_distributions
> for info)
>
> Beyond that, the upgradeany path is probably the least tested of all the
> anaconda install paths, and will likely traceback at the worst possible
> time.  Upgrades aren't easy (even on Debian/Ubuntu where packages being
> upgraded can ask questions and do significant things, unlike in the RPM
> scriptlet case).  Preupgrade has failed for me more than it has worked,
> going through several revs of Fedora.
>
> Having said all of that, if you analyze your particular package set and
> you figure out that all of the packages have identical configs between FC2
> (or EL4, for that matter) and EL5, and that you're not using a package
> that has had major changes and upgrades break data (like PostgreSQL; FC2
> shipped a significantly older PostgreSQL than CentOS 5 does, and a major
> version upgrade on PostgreSQL requires some special handling), you might
> be able to get it to work.
>
> But it will probably take more time to successfully upgrade than it will
> to do a fresh install with the same list of packages and a restore of
> compatible configurations onto that fresh install.  But, it's your time to
> waste if you want to do so.
>
> If you want to see this sort of thing on the MS OS, there is a YouTube
> video out there highlighting upgrading through all versions of Windows;
> the cruft leftover from Window 1.0, 2.0, and 3.x in a Windows 7 upgraded
> system is a thing to behold.
>
> _______________________________________________
> CentOS mailing list
> CentOS at centos.org
> http://lists.centos.org/mailman/listinfo/centos
>