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rhb100
1st April 2009, 02:12 AM
I have Fedora Core 8 installed. I would like to reinstall it so as to get back commands that have been lost. To preserve my user data that has been stored in logical volumes, what selections should I make in the installation process? Are these selections essentially the same for Fedora Core 10?

Draciron
3rd April 2009, 09:12 AM
When your reinstalling choose custom layout. Then each of the partitions except / and swap assuming you have / and swap as separate partitions, click on the partition, choose the mount name for it, for example /data or /lvm1 or whatever you want it to mount as. Then select LVM from the file system type drop down. Make sure the format partition button is unclicked for partitions you want to save.

Never use LVM for you / partition. LVM partitions occasionally have glitches and if LVM goes down and / is mounted as LVM you'll have to reboot into a rescue CD to fix the problem. If / is ext 3 and LVM pitches a fit all you need do often as not is restart LVM and the problem goes away. Sometimes you have to run the LVM utils but in every case it's a whole lot easier that way than rebooting. It is usually wise not to use LVM on /home either for same reason. LVM goes down you'll have to log in as root to fix it as all of the users will be out of commission except root until you fix the LVM problem.

/ you'll want to reformat. Any data you have on / you should move to another partition before reinstalling. If you reinstall without formating / you risk dependancy issues and other problems caused by vestige libs and applications from your previous install.

rhb100
3rd April 2009, 08:29 PM

Thank you for your reply. I decided to go ahead and install Fedora Core 10 before I received your reply. However, I find some of your comments about LVM useful and interesting. I chose the custom layout, reformatted /boot and lvroot, but left lvhome unchanged so as to retain my data.

After I completed installation, I noticed that my data was not found in my home directory. I later figured out than I needed to mount logical volume lvhome. I created a new directory called home_new and mounted lvhome at that point. I did then find my data in home_new. However as I was attempting
mv home home_old
followed by
mv home_new home
the system stopped working.

I then reinstalled Fedora Core 10 without logical volumes and put the backup of my data into home/rhb100. I have decided that LVM causes more problems than benefits. Your remarks on the problems with LVM further convince me of this fact.

markkuk
4th April 2009, 10:25 AM
After I completed installation, I noticed that my data was not found in my home directory. I later figured out than I needed to mount logical volume lvhome. I created a new directory called home_new and mounted lvhome at that point.
You should have mounted lvhome in /home, you could have defined that during the installation process and avoided all the problems.

Draciron
4th April 2009, 10:49 AM
LVM is best used for partitions that have variable space needs. I typically use it on multi-function servers such as a web server that is also a home dir server for windoze users. By creating separate partitions for both and leaving space free I'm able to adjust as needed to the disk space demands. If I get low on diskspace I can change the quotas on the home dir partition, force a clean up and add space to the web server for example. On a home PC the only time I usually use it is with the data dirs. For example I may be scanning large numbers of photos as part of a geneological project I'm doing for my family which eats up massive space, but then when done I want to return that space to the partition I record music on.

Primarily I use it for servers though. Never for / or /home unless /home is serving up home dirs for networked machines. Unless I'm single tasking a server databases always live on an LVM partition if I expect heavy usage. Web servers the same way.

rhb100
5th April 2009, 03:46 AM
I think Draciron is correct that LVM is best used for partitions that have variable space needs. I also thank that Markhuk is probably right in saying that I should have mounted lvhome on /home as a part of installation.

But I think that Fedora is inconsistent in making LVM the default for installation while failing to provide a default method for upgrading an LVM installation.