Hi Chris, Yes, I discovered the hard way last night that my idea will not work. After following the steps I myself outlined earlier -- it looks like both logical volumes within the volume group /dev/VolGroup00 were trashed. That means LogVol00 (which I think housed / ) and LogVol01 (which I think was swap.) /boot appears to be intact since it is outside of the LVM, but as soon as I did my partition shrinking procedure, and rebooted, the kernel panicked. I can't get the kernel messages to stop long enough for me to read them but I suspect the panic is because the kernel couldn't mount LogVol00. I do get the impression that shrinking an lvm is a destructive process. It blows the filesystem away. Or perhaps my mistake was one of not getting the new lvm sizes all perfectly matched -- fdisk and lvresize. I do have a backup of most of my critical files, so I can reinstall from scratch today or whenever and not feel too much pain. I hope. Thanks Bob Cochran > -----Original Message----- > From: Chris Tyler [mailto:chris@xxxxxxxxxxx] > Sent: Monday, June 4, 2007 03:03 AM > To: fedora-list@xxxxxxxxxx > Cc: 'Robert L Cochran' > Subject: Re: Resizing an LVM > > On Sun, 03 Jun 2007 17:37:12 -0400 Robert L Cochran wrote: > > Here is what I believe I need to do. > > > > 1. Boot the Fedora 7 DVD in rescue mode. > > 2. Do not mount the file system, instead just go to a shell prompt and > > 3. lvm vgscan > > > > Gets the name of the volume group > > > > 4. lvm vgchange -a y /dev/VolGroup00 > > > > Activates the volume > > > > 5. e2fsck -f /dev/VolGroup00/LogVol00 > > > > Checks file system for errors > > > > 6. resize2fs /dev/VolGroup00/LogVol00 119G > > > > shrinks the file system down to 119 Gb > > > > 7. fdisk > > > > shrinks size of partition > > Unfortunately, this will not work, because shrinking the LV will not > reduce the size of the PV. > > If you need real partitions (not LVs) for the other operating systmes, > you are at the present time out of luck for a direct conversion, because > pvresize has not been implemented (see the manpage for lvm). > > What you could do, though, is temporarily attach another disk (IDE, USB, > or FireWire), then: > > 1. Create a partition on the temp disk (fdisk). > 2. Make that partition a PV (pvcreate). > 3. Add that partition to your volume group (vgextend). > 4. Migrate the data off the old PV to the new one (pvmove). > 5. Remove the original PV from the VG (vgreduce) > 6. Recreate the PV on the original disk, smaller than before. (fdisk > followed by pvcreate). > 7. Add the recreated PV to the VG (vgextend). > 8. Migrate the data from the temp disk to the original disk (pvmove). > 9. Remove PV on the temp disk from your VG (vgreduce). > > This is why it's a good idea, when setting up a new large disk for use > with LVM, to divide the disk into multiple partitions and use all of > them as PVs in the VG (instad of creating one big PV) -- it gives you > more flexibility to later move some of that space out of the VG so it > can be used for something else. (It also lets you do an in-situ > migration to RAID; if, for example, you have 5 PVs, you can migrate to > RAID PV-by-PV as long as you have 20% free space in your VG). > > -- > Chris Tyler > Fedora Daily Package - http://dailypackage.fedorabook.com > >
