I'm very much a Linux newbie so I hope this isn't too obvious...
I'm running Fedora Core 3 on a machine with 2 drives. The default configuration after install was that everything under root is mounted as /dev/VolGroup00/LogVol00. This volume group contains both my physical partitions (/hda2 and /hdb1).
What I would like to do is create 2 Volume Groups with one physical drive in each group. This way I can use one drive as a backup in case the other drive crashes.
pvmove /dev/hdb1 /dev/hda2
but was told that I need 915 allocatable extents. Ok, I figured that I could try to make some space using:
lvreduce -l 1000 VolGroup00/LogVol00
but I got scared from the resulting warning which made me think I needed to reduce the size of the root filesystem first. So I tried:
resize2fs /dev/VolGroup00/LogVol00 8000000
figuring that would give me 8 Gigs of free space allowing me to reduce the logical volume accordingly, but of course was told that I needed to unmount the root filesystem first!
So... how can I keep working on the machine while unmounting the root filesystem? Is there some way around this? A special boot up mode for working with LVM?
Any help would be greatly appreciated.