Switching between Linux distros - what steps to take?

Looking for a smooth transition

[brakthepoet]

I'm ready to change Linux distros since RH9 reached end of life last month. I've been searching the web & usenet for some good advice on the process of switching between distros, but haven't found much good information. (I promise, guys, I've tried to study up before raising my hand. I want to come to class prepared.) I'm finding lots of stuff for switching from Windows to Linux and choosing a distribution, but not much regarding a switch between distros.

I'm not concerned with what distro I go with, so anything is up as an option. I want to be sure that what I've saved/developed on my current machine moves to the new distro without many problems. It would seem that I mostly just need to backup the /home directory(s), install the new distro, and copy the /home directory(s) files to the newly installed OS. I also assume that I'll have to re-install some software that doesn't come with a basic install.

What other steps would the resident Linux gurus recommend for switching distros? Or am I headed in totally the wrong direction to begin with?

[nalin]

This might be more applicable to reinstalling the same distro but here it goes:

I generally backup
/home,
/root,
/etc
(and dependant upon system you might want parts of /var for instance if its a webserver logfiles and apache root dir)

I place all this stuff in an unused partition.

When reinstalling I reformat all but the unsued partitions, reinstall, and then selectively take what I need from the old system. The /etc tends to be the invaluable one (use gentoo here so there you start out with a command line editor and a long set of instructions, and prebuilt /etc files save lots of time and typos), as generally I can go without 90% of the crap that builds up in my home dir.

To this end I have a partition that is used exclusively for this task (one might ask why I dont rid myself of reiserfs or get a battery backup, but that would be way too easy), and have some of the aforementioned stuff on different mountpoints just to allow it to be easily reused.

edit: ----------------------------------
Also note that if you have the diskspace or can make it its not a bad idea to dual boot two distros (actually this would be most painless)

Dependant upon the distro you choose and the installation options it may / will likely want to overwrite your mbr - if you print your current /boot/grub/grub.conf or its lilo counterpart and integrate this into the new bootloader configuration file you should have very painless access to the new system while having a few weeks or months to salvage anything from the old.

[encyclo]

The easiest upgrade from RH9 would undoubtedly be to Red Hat Fedora Core 2 - I believe the Fedora installer offers an upgrade option, but even if not, the transition should be reasonably painless. Fedora is the diect descendant of RH9, and it would have been RH10 were it not for the change in marketing tactics by Red Hat. You'll feel very much at home!

The only thing you need to back up is

/home

. If you've got stuff like virtual servers in Apache, mailservers or the like, you also need to backup the configuration files at the very least. Of course if you back up everything, you can switch back to RH9 if the install of Fedora goes haywire (it shouldn't).

[brakthepoet]

Thanks nalin & encyclo, you've got me started in the right direction.

I have Fedora Core 1 on my laptop, and it does seem much like RH9. I'm a bit skeptical of an upgrade option, but that's probably because of my experiences with Windows upgrades. I'll look it over, though.

I hadn't thought about searching for reinstallation information, as that sounds closer to what I'm doing now.

[danny]

I've done multiple RH9 to FC1 upgrades, with no problems. I've even done some without an install, following instructions from Alan Cox:

Install fedora-release and yum packages from CD#1 of FC1
yum update rpm
rpm --rebuilddb
yum update krb5-libs e2fsprogs
yum update
reboot

[jam13]

Or you could extend the life of RH9 somewhat by using one of the unofficial package repositories. The Fedora legacy project are supposed to be providing security patches for RH9 for another 18 months from EOL:

[fedoralegacy.org...]

We have moved to Fedora for many of our installs, but given the short lifespan (even with extended support from projects like the one above) this decision may prove to be hard to live with :(