Changing Linux versions

[wjgollatz]

I will be receiving a new system much quiker than I thought - in 10 days as opposed to 4 weeks - so I will have less research time than what I thought. I have never used Linux before. If I install one particular version of Linux - and I don't like it, what are the problems or steps involved to removing it, and installing a new version, with backing up any data that I created? Should the parition be formatted like a Windows disc should be - can partitions even be formatted?

 

[drag]

The file system/partition sceme is very similar to Windows...

different filing system scemes, of course. Linux can't use NTFS, but has several to choose from. Ext3 is a safe bet.

Also Linux uses a seperate swap partition, unlike a swap file that is used in Windows.

Also Linux doesn't use C: D: E: drives or anything like that. Everything is part of a overall directory tree. Starting at / which is called "root". Every filing system (except swap partition) is mounted as a directory of that directory tree. It's makes for a much more transparent setup then what you get with Windows. For instance if you want home folders to be a from a remote file server and use it for many different computers, as a sort of "roaming profile" you just share it using NFS and mount it to /home/ and when people log in they have their home folder on that network share, and to them it's as if it's realy a local disk.

Same for floppies and cdroms even.

So what I like to do is have one big / (root) partition were most my applications go. Then I have a 1 or 2 of swap partition, and then a seperate /home partition. That way if I decide to change distros I can just format and blow away the OS, but still be carefull to keep my /home partition untouched. Then when I install a new distro all my user files are untouched. My user preferences and such can even survive intact between distros with no problem. (although going from version to a new version of applications can cause problems if the version that is installed is very different from the previous distros version).

The one caveat is that Linux displays user ownership using username and groupname, however it realy keeps track of it using UID and GID numbers, which may or may not be the same between each install. The fix is simple though. Before logging in as your user log in as root and issue a change of ownership command like such:
chown -R username:groupname /home/username

For instance I use the same name for my username and main group. So my command would go:
chmod -R drag:drag /home/drag

And that will fix the permissions so that your user can use your files with no problem.

Also user preferences are stored inside the actual home directory unlike Windows which has a universal single registry file...

These files are normally not seen because they have a . at the beginning of the filename. (also the shortcut ~/ is the wildcard that means /home/my.username) so to see these configuration files and directories you go:
ls -al ~/.*
and that will show all your hidden files.

So if any preferences get screwed up, delete the file or directory and it will be regenerated from defaults the next time you use your application. The only exceptions are stuff like Gnome apps that use a singular .gconf directory that it uses for most apps. Sometime you have to get creative...

Just becarefull with configuration directories for things like Evolution (e-mail client) or Mozilla/Firefox because you don't want to loose your bookmarks and saved mail files. Before screwing with their configurations backup their data you want to keep safe.

However keep in mind that your system-wide configurations are stored in the /etc/ directory. Be very carefull with those and back them up before editing them. If you blow them away they are gone forever and it can render your system non-functional. They don't work the same as user preferences.

So that way you can maintain your user directory between different system installs, and even different OSes. If you need to move them to a new harddrive or a different server you can simply wrap them up in a big tarball (linux equivalent of a zip file) and copy them over and untar it. Also any realy custom configurations you want to save, simply copy the text configuration files and keep them around to be copied between machines or into a new install (keeping in mind the differences between versions, of course Major version numbers usually indicate incompatabilities with older versions. Like for instance you can expect Evolution 1.0 stuff to work reasonably well with Evolution 1.4, but not with Evolution 2.0), but that's usually not worth it unless you put a lot of effort behind specific configurations.

 

[DouglasAdams]

why would you need 2 swap files drag?

 

[drag]

Sorry, I said:
Then I have a 1 or 2 of swap partition,

I ment to say:
Then I have a 1 or 2 gigs of swap partition,

hehe. Sorry for the misunderstanding.

Also it only gets a little bit complicated if you want to save your home files from distro to distro. If you backups and don't mind blowing everything away, then just format the partitions then install the new distro on your computer, like you would with windows. It won't cause any issues.

 

[DouglasAdams]

Originally posted by: drag
like you would with windows

actually drag, i've always installed windows to 1 drv/partition and put my data on a different drv/partition - a trick i learned in the days before dos 3.11

if i wanted to do the same with Linux (as yet undecided between choc-chip and cafe latte), i.e. the equivalent to transfering windows "my documents" to a D: drive, would simply relocating my "home" (yes, i've found where to do that) do the trick?? fyi, the machine i'm setting up is planned to be a file/print server; a play thing to learn Linux and a bitch for running/sending SETI@home but i hope to transfer more and more data (i.e. "work") to it and i'd hate it to disappear. btw, my present windows backup method is to rar all my data ("my documents") onto a second drive then throw the rar files to a cd-rw periodically. would making a tar ball of my "home" do the same? ... or better?

 

[uOpt]

wjgollatz, what you should do is install the OS and applications shipped with the OS to one root partition but keep everything else not belonging to the OS on a seperate partition. That way if you decide you want to try a different distribution then you just wipe out the root partition and mount your user stuff.

Example stuff that you keep in the second partition:
- you homedir and all you data including photos, mp3, videos, config files and documents of all kind
- software that you install outside the rpm system, i.e. to /usr/local. Keep /usr/local/ on the second partition using a symlink
- stuff you downloaded, e.g. rpms not belonging directly to one distribution that you will want to install on the new distribution

The first one is easy to ensure since if you use your user account you can only write to your homedir anyway, apart from /tmp and /var/tmp.

You can also have two or more distributions at the same time, both accessing the same /home and /usr/local. Might be the best way to compare them.

 

[uOpt]

Slight correction, BTW, Linux does support NTFS but it is very new and many distributions don't have it supported by default.

If you install a Windows on a machine that you will run Linux on later FAT is the time-saving choice.

 

[drag]

Originally posted by: DouglasAdams

Originally posted by: drag
like you would with windows

actually drag, i've always installed windows to 1 drv/partition and put my data on a different drv/partition - a trick i learned in the days before dos 3.11

if i wanted to do the same with Linux (as yet undecided between choc-chip and cafe latte), i.e. the equivalent to transfering windows "my documents" to a D: drive, would simply relocating my "home" (yes, i've found where to do that) do the trick?? fyi, the machine i'm setting up is planned to be a file/print server; a play thing to learn Linux and a bitch for running/sending SETI@home but i hope to transfer more and more data (i.e. "work") to it and i'd hate it to disappear. btw, my present windows backup method is to rar all my data ("my documents") onto a second drive then throw the rar files to a cd-rw periodically. would making a tar ball of my "home" do the same? ... or better?

Well it would save all your data + user preferences, So I figure, maybe a little bit better. But backups are backups not much difference between OSes. A compressed tarball is a good way to do backups....

for a big overview check out:
http://www.charlescurley.com/L...overy-HOWTO/index.html

 

[cquark]

Originally posted by: DouglasAdams

Originally posted by: drag
like you would with windows

actually drag, i've always installed windows to 1 drv/partition and put my data on a different drv/partition - a trick i learned in the days before dos 3.11

if i wanted to do the same with Linux (as yet undecided between choc-chip and cafe latte), i.e. the equivalent to transfering windows "my documents" to a D: drive, would simply relocating my "home" (yes, i've found where to do that) do the trick?? fyi, the machine i'm setting up is planned to be a file/print server; a play thing to learn Linux and a bitch for running/sending SETI@home but i hope to transfer more and more data (i.e. "work") to it and i'd hate it to disappear. btw, my present windows backup method is to rar all my data ("my documents") onto a second drive then throw the rar files to a cd-rw periodically. would making a tar ball of my "home" do the same? ... or better?

You might find rsync easier and faster, as it synchronizes the two directory hierarchies by copying the differences between them. There's also rsnapshot, a easy-to-use backup system based on rsync.

 

[cquark]

Originally posted by: wjgollatz
I will be receiving a new system much quiker than I thought - in 10 days as opposed to 4 weeks - so I will have less research time than what I thought. I have never used Linux before. If I install one particular version of Linux - and I don't like it, what are the problems or steps involved to removing it, and installing a new version, with backing up any data that I created? Should the parition be formatted like a Windows disc should be - can partitions even be formatted?

It's easy, as others have suggested. Just use a separate partition for your / (root) and /home directory hierarchies. When you install a different Linux distribution, let it overwrite the system and application files under / (root) and tell it not to do anything with /home. I've got both Debian and Fedora on my primary system, both with their own / (root) partition, but using the same /home partition.

I'd recommend trying Knoppix, as you can try it from the CD, then use the Knoppix Installer to turn your configuration into a working Debian system on your hard disk.