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Steltek
08-03-2004, 10:57 AM
I need a Knoppix disk (or any other live distro) capable of detecting LVM2 volumes and resizing them (plus resizing and ext3 filesystem contained on it). The DVD packages list only shows lvm-common and lvm10 (so lvm2 seems to be missing) but I'm not sure whether that list is complete.

Edit: Of course I also need LVM2 support in the 2.6.x kernel for the distro to be of any use to me.

Steltek
08-05-2004, 07:53 AM
Replying to myself: you can ignore this, I've managed to get LVM2 to work with the current Knoppix 3.4 and successfully extended a vg (yes, I could've done this online) and a logical volume and resized the ext3 filesystem on that lv (this was a root on LVM2 box, thus the need to do these operations from a live CD).

In case anybody is interested, here's how I did it:

- First, boot knoppix26 (well duh, I doubt we can get LVM2 to work in Kernel 2.4 ;) ).
- Now we have two possible ways to proceed, we can either use apt-get to download the packages we need or we can download them manually.

With apt-get:
I think apt-get used to work on some older Knoppix CDs, nowadays it won't run directly so you need to go to services -> Install software while running from CD -> apt-get. Once you have done this, open a console and do 'apt-get update' and then 'apt-get install lvm2 dmsetup' (as user 'knoppix', not as root).

Manual download:
Go to http://packages.debian.org and search for the packages lvm2 and dmsetup in the 'unstable' distribution. Download the deb files for i386 from there and store them somewhere on /ramdisk.

- Next, open a console and become root.
- Start Midnight Commander (mc) and navigate one of the panes to /ramdisk and the other to where you stored the .deb files you downloaded (if you downloaded them with apt-get they are in /ramdisk/home/knoppix/.dist/var/cache/apt/archives).
- Open the .debs with Midnight Commander (position the cursor on them and hit enter, just like you'd do to enter a subdirectory), go into the cirtual 'CONTENTS' subdirectory, select everything there and copy it to /ramdisk (hit F5).
- Once you've extracted the .debs you can close mc again.
- Last but not least, change the path. To do this, type export and see the PATH= variable, it will be something like PATH="/sbin:/bin:/usr/sbin:...... copy (as in copy/paste) the part after the double quote, type 'export PATH="/ramdisk/lib/lvm-200:/ramdisk/sbin:' and then paste the original PATH contents after that.
- mkdir /dev/mapper
- cd /dev/mapper
- mknod control c 10 63
- Load the device-mapper module required for LVM2 (type modprobe dm-mod).

That's it. You can now run the usual commands like vgscan, vgchange, pv/vg/lvcreate, ... on your LVM2 volumes.

In case you want to resize an ext3 root volume like I did you can now proceed to extend the lv, run e2fsck -f on it, use debugfs to 'demote' it to ext2, run resize2fs on it, use tune2fs -j to make it ext3 again, mount it on /mnt2 (I always create /mnt2 and mount there, I don't like Knoppix creating mountpoints in whatever I mounted directly to /mnt), mount --bind /proc and /sys to /mnt2/proc and /mnt2/sys respectively, chroot /mnt2 and then lilo -v to reinstall your bootloader (I did that just for good measure. given the fact that neither kernel image nor initrd got moved in the resizing procedure it would probably have booted without going through all the steps to reinstall lilo), umount /mnt2, reboot and enjoy your bigger /.

sireasoning
01-21-2005, 07:58 AM
follow the directions above, however you will need to remove /dev/mapper before mkdir /dev/mapper (as /dev/mapper is actually a link to the live-cd and therefore read-only).
rm -Rf /dev/mapper
mkdir /dev/mapper
and continue with the rest of the instructions....

Personally I think it should be part of knoppix and not require such dramatics. Dev-mapper is already included and should be copied over to /etc instead of linked, then they could install lvm2 and run it on both kernels. It is a small program and would be trivial to implement.