How to change from one distro to the next?

@darkstar:

I'm relatively new in UML….I have installed RH9 on my server… does anybody know how to change the distro to another (say Fedora) without wiping out all the existing data and configuration?

It all depends on how much you have setup, and where.

The very first thing you must do is make one big backup of everything, and an Offsite location.

After doing this, you have two ways of going about switching distros.

The first is to create a partition, that will hold all the data while you are switching distros. This way that partition is never touched, and the data on it is safe.

The second is to simply make another backup of your files. Dump them to an offsite location. Install the new distro. Put back the files in the correct places via the second backup. (The second backup is DIFFERENT than the first, for obvious paranoid reasons.)

One big question that remains is which files need to be copied over. This greatly depends on what you have installed, and how much you plan to copy over.

If you have multiple users, then you may want to copy over /etc/passwd, /etc/group and /etc/shadow*. Additionally you will want to make a backup of your /home dir.

If you use the unix standard mail spool, then you might want to copy /var/spool/mail. If you run an HTTP server, then you want to look at your httpd.conf file to see which dirs are being used, and properly copy them over to. You must do this for all services you run.

big hassel huh?

What Unix people often do is have a seperate partition for user data and such. I personally stick everything in /home. This way, when I want to upgrade distributions as well, I can easily do so without worrying about losing data on /home.

So the next time you install a distro, keep everyhting in a few easy to manage places so that when you need to change distros, the chance of data loss will be minimal.

Bill Clinton

It seems to me like the guy just wants to test out another distro and see what it's like :)

If that's the case, you need to check the remaining total disk space from the Linode control panel (NOT in SSH). If there isn't enough for a Fedora installation (~500MB), log into your RH9 shell and type df to see how much is actually being used. Now shut down the RH9 linode from the control panel and view your disk partitions - choose to resize the RH9 partition to the value you got from typing df earlier (plus another 50MB for peace of mind). This should leave you with enough space to enter the Distro Wizard and create a Fedora distribution. Note that you won't be able to instantly access files from the RH9 distro, Bill's post above covers that. From then on it's a simple case of choosing which one you want to boot.