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problem mounting LVM

Hello

I am having a problem mounting an LVM partition. Basically , I have had to do a fresh install of centos4.2 on a new drive. I need to mount the root partition from the old drive. The old drive is not damaged in anyway and still works. I need to mount /dev/hdc2 so i can access the data. Here are my results:

[root@server /]# mount /dev/hdc2 /oldroot
mount: /dev/hdc2 already mounted or /oldroot busy

Here is the fdisk -l info:

Device Boot Start End Blocks Id System
/dev/hda1 * 1 13 104391 83 Linux
/dev/hda2 14 274 2096482+ 82 Linux swap
/dev/hda3 275 535 2096482+ 83 Linux
/dev/hda4 536 24321 191061045 5 Extended
/dev/hda5 536 24321 191061013+ 83 Linux

Device Boot Start End Blocks Id System
/dev/hdc1 * 1 13 104391 83 Linux
/dev/hdc2 14 9729 78043770 8e Linux LVM

/dev/hdc1 obviously has no issue mounting. The /oldroot directory in which i am trying to mount to is completely empty and is does not have any partitions mounted to it. Any help/suggestions would be awsome.

Thank
Conal

surely the old root wont be in your lvm tab? also, you dont specify a file system type in your mount command....

It's telling you something is already in use/busy.

Try running lsof against both the device and the mount point to see if either is in fact actually in use.

You don't mount an LVM partition directly. You mount the logical volumes contained within the LVM partition. The error message you're getting is misleading, to say the least. But I think the root cause of your problem is the incorrect way you're attempting to use the partition.

See the LVM mounting example from my system below. I have LVM on /dev/sd8 but you can see that /dev/sd8 is NOT directly mounted anywhere. The individual LV's inside the LVM partition are mounted, e.g., /dev/mapper/vg0-usr is mounted on /usr, /dev/mapper/vg0-var is mounted on /var, etc.

Code:

# fdisk -l



Disk /dev/sda: 160.0 GB, 160000000000 bytes

255 heads, 63 sectors/track, 19452 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes



  Device Boot      Start        End      Blocks  Id  System

/dev/sda1              1        5099    40957686    7  HPFS/NTFS

/dev/sda2            5100      10199    40965750    7  HPFS/NTFS

/dev/sda3          10200      14024    30724312+  c  W95 FAT32 (LBA)

/dev/sda4          14025      19452    43600410    f  W95 Ext'd (LBA)

/dev/sda5  *      14025      14030      48163+  83  Linux

/dev/sda6          14031      14091      489951  82  Linux swap / Solaris

/dev/sda7          14092      14213      979933+  83  Linux

/dev/sda8          14214      19452    42082236  8e  Linux LVM

# mount

/dev/sda7 on / type ext3 (rw,errors=remount-ro)

proc on /proc type proc (rw)

sysfs on /sys type sysfs (rw)

devpts on /dev/pts type devpts (rw,gid=5,mode=620)

tmpfs on /dev/shm type tmpfs (rw)

usbfs on /proc/bus/usb type usbfs (rw)

/dev/sda5 on /boot type ext3 (rw)

/dev/mapper/vg0-usr on /usr type ext3 (rw)

/dev/mapper/vg0-var on /var type ext3 (rw)

/dev/mapper/vg0-opt on /opt type ext3 (rw)

/dev/mapper/vg0-tmp on /tmp type ext3 (rw)

/dev/mapper/vg0-home on /home type ext3 (rw)

/dev/sda1 on /mnt/windows/c type ntfs (ro,umask=0222)

/dev/sda2 on /mnt/windows/d type ntfs (ro,umask=0222)

/dev/sda3 on /mnt/windows/e type vfat (rw,umask=0000)

tmpfs on /dev type tmpfs (rw,size=10M,mode=0755)

#

Here are the LVM related entries in my /etc/fstab:

Code:

...

#

# Logical Volume Management (LVM2 on /dev/sda8)

# Note: /usr/local is symlinked to /opt

#

/dev/mapper/vg0-usr  /usr      ext3    defaults                    0      2

/dev/mapper/vg0-var  /var      ext3    defaults                    0      2

/dev/mapper/vg0-opt  /opt      ext3    defaults                    0      2

/dev/mapper/vg0-tmp  /tmp      ext3    defaults                    0      2

/dev/mapper/vg0-home /home      ext3    defaults                    0      2

...