[CentOS] Removing LVM

Tue Apr 10 16:52:07 UTC 2012
James Pifer <jep at obrien-pifer.com>

On Tue, 2012-04-10 at 04:59 +0200, Markus Falb wrote:
> On 10.4.2012 02:42, James Pifer wrote:
> > I have a CentOS 5 machine in which I'm trying to remove lvm. I dd'ed the
> > file system to another partition, then dd'ed it back overwriting the lvm
> > partition. I then modified menu.lst and fstab and replaced the paths to
> > point to the correct device. 
> > 
> > When the system boots it's still looking for lvm. I can restore the
> > system back to where it was with lvm, but I'm not sure what step I'm
> > missing to stop the system from looking for lvm. 
> Extract the initrd, edit the init script (I do not remember the name)
> and compress initrd again. I had to this some time ago after renaming a
> Volume Group. There is some lvm stuff hardcoded in this script.


Thank you for the suggestion. I'm very close, I think. I used the
instructions here for working with initrd's script:

I'm still having a problem booting up. I can't seem to figure out what
the proper settings should be in initrd. When I boot I get:

Loading dmmemcache.ko module
Loading dmregion_hash.ko module
Loading dmmessage.ko module
Loading dmraid45.ko module
devicemapper: dmraid45: initialized v0.2594l
Waiting for driver initialization.
Scanning and configuring dmraid supported devices
Trying to resume from /dev/sda2
Unable to access resume device (/dev/sda2)
Creating root device.
Mounting root filesystem.
mount: could not find filesystem ’/dev/root’
Setting up other filesystems.
Setting up new root fs
setuproot: moving /dev failed: No such file or directory
no fstab.sys, mounting internal defaults
setuproot: error mounting /proc: No such file or directory
setuproot: error mounting /sys: No such file or directory
Switching to new root and running init.
unmounting old /dev
unmounting old /proc
unmounting old /sys
switchroot: mount failed: No such file or directory
Kernel panic  not syncing: Attempted to kill init!

Here are my relevant files:
fdisk -l
Disk /dev/sda: 53.7 GB, 53687091200 bytes
255 heads, 63 sectors/track, 6527 cylinders, total 104857600 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xea6c011f

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *          63      208844      104391   83  Linux
/dev/sda2          208845     4401809     2096482+  82  Linux swap / Solaris
/dev/sda3         4401810    46122614    20860402+  83  Linux

/dev/sda3               /                       ext3    defaults        1 1
#LABEL=/                        /                       ext3    defaults        1 1
LABEL=/boot             /boot                   ext3    defaults        1 2
tmpfs                   /dev/shm                tmpfs   defaults        0 0
devpts                  /dev/pts                devpts  gid=5,mode=620  0 0
sysfs                   /sys                    sysfs   defaults        0 0
proc                    /proc                   proc    defaults        0 0
/dev/sda2               swap                    swap    defaults        0 0

# grub.conf generated by anaconda
# Note that you do not have to rerun grub after making changes to this
# NOTICE:  You have a /boot partition.  This means that
#          all kernel and initrd paths are relative to /boot/, eg.
#          root (hd0,0)
#          kernel /vmlinuz-version ro root=/dev/VolGroup00/LogVol00
#          initrd /initrd-version.img
title CentOS (2.6.18-274.17.1.el5)
        root (hd0,0)
        kernel /vmlinuz-2.6.18-274.17.1.el5 ro root=/dev/sda3
        initrd /initrd-2.6.18-274.17.1.el5.img
title CentOS (2.6.18-274.3.1.el5)
        root (hd0,0)
        kernel /vmlinuz-2.6.18-274.3.1.el5 ro root=/dev/sda3
        initrd /initrd-2.6.18-274.3.1.el5.img
title Centreon Enterprise Server (2.6.18-194.3.1.el5)
        root (hd0,0)
        kernel /vmlinuz-2.6.18-194.3.1.el5 ro root=/dev/sda3
        initrd /initrd-2.6.18-194.3.1.el5.img

initrd init:

mount -t proc /proc /proc
echo Mounting proc filesystem
echo Mounting sysfs filesystem
mount -t sysfs /sys /sys
echo Creating /dev
mount -o mode=0755 -t tmpfs /dev /dev
mkdir /dev/pts
mount -t devpts -o gid=5,mode=620 /dev/pts /dev/pts
mkdir /dev/shm
mkdir /dev/mapper
echo Creating initial device nodes
mknod /dev/null c 1 3
mknod /dev/zero c 1 5
mknod /dev/urandom c 1 9
mknod /dev/systty c 4 0
mknod /dev/tty c 5 0
mknod /dev/console c 5 1
mknod /dev/ptmx c 5 2
mknod /dev/rtc c 10 135
mknod /dev/tty0 c 4 0
mknod /dev/tty1 c 4 1
mknod /dev/tty2 c 4 2
mknod /dev/tty3 c 4 3
mknod /dev/tty4 c 4 4
mknod /dev/tty5 c 4 5
mknod /dev/tty6 c 4 6
mknod /dev/tty7 c 4 7
mknod /dev/tty8 c 4 8
mknod /dev/tty9 c 4 9
mknod /dev/tty10 c 4 10
mknod /dev/tty11 c 4 11
mknod /dev/tty12 c 4 12
mknod /dev/ttyS0 c 4 64
mknod /dev/ttyS1 c 4 65
mknod /dev/ttyS2 c 4 66
mknod /dev/ttyS3 c 4 67
echo Setting up hotplug.
echo Creating block device nodes.
echo "Loading ehci-hcd.ko module"
insmod /lib/ehci-hcd.ko
echo "Loading ohci-hcd.ko module"
insmod /lib/ohci-hcd.ko
echo "Loading uhci-hcd.ko module"
insmod /lib/uhci-hcd.ko
mount -t usbfs /proc/bus/usb /proc/bus/usb
echo "Loading jbd.ko module"
insmod /lib/jbd.ko
echo "Loading ext3.ko module"
insmod /lib/ext3.ko
echo "Loading scsi_mod.ko module"
insmod /lib/scsi_mod.ko
echo "Loading sd_mod.ko module"
insmod /lib/sd_mod.ko
echo "Loading scsi_transport_spi.ko module"
insmod /lib/scsi_transport_spi.ko
echo "Loading mptbase.ko module"
insmod /lib/mptbase.ko
echo "Loading mptscsih.ko module"
insmod /lib/mptscsih.ko
echo "Loading mptspi.ko module"
insmod /lib/mptspi.ko
echo "Loading libata.ko module"
insmod /lib/libata.ko
echo "Loading ata_piix.ko module"
insmod /lib/ata_piix.ko
echo "Loading dm-mod.ko module"
insmod /lib/dm-mod.ko
echo "Loading dm-log.ko module"
insmod /lib/dm-log.ko
echo "Loading dm-mirror.ko module"
insmod /lib/dm-mirror.ko
echo "Loading dm-zero.ko module"
insmod /lib/dm-zero.ko
echo "Loading dm-snapshot.ko module"
insmod /lib/dm-snapshot.ko
echo "Loading dm-mem-cache.ko module"
insmod /lib/dm-mem-cache.ko
echo "Loading dm-region_hash.ko module"
insmod /lib/dm-region_hash.ko
echo "Loading dm-message.ko module"
insmod /lib/dm-message.ko
echo "Loading dm-raid45.ko module"
insmod /lib/dm-raid45.ko
echo Waiting for driver initialization.
stabilized --hash --interval 1000 /proc/scsi/scsi
echo Scanning and configuring dmraid supported devices
resume /dev/sda2
echo Creating root device.
mkrootdev -t ext3 -o defaults,ro /dev/sda3
echo Mounting root filesystem.
mount /sysroot
echo Setting up other filesystems.
echo Switching to new root and running init.

Any ideas?