[linux-lvm] Logical Volume Inaccessible

Tom+Dale tdmyth at yahoo.com
Sun Jan 12 04:28:08 UTC 2014



I am hoping that someone can assist me with a problem that I have on a 
single 500GB drive that was partitioned by "Mythdora" a (now defunct) 
distribution of Fedora + MythTV.  I had this system in use for several 
years and recently the motherboard died.  When I put the hard disk into a different machine it would not boot up (no surprise); however, I also 
was unable to access the partitions from a Knoppix Live CD (I tried both 5.1 and 7.0).  When I tried with Knoppix to mount the partitions I 
discovered that something is wrong with the partition tables or logical 
volumes.  Here are some examples of the commands that I tried along with the results.  Will you please give me some advice about the best way to recover data from sda2 (the recordings)?  Thank you in advance!
-Tom

---------------------------------------------
root at Microknoppix:/# fdisk -l

Disk /dev/sda: 500.1 GB, 500107862016 bytes
255 heads, 63 sectors/track, 60801 cylinders, total 976773168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x000537fa

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *          63      409662      204800   83  Linux
Partition 1 does not start on physical sector boundary.
/dev/sda2          409663   976768064  
 488179201   8e  Linux LVM
Partition 2 does not start on physical sector boundary.
root at Microknoppix:/# parted -l
Model: ATA WDC WD5000AADS-1 (scsi)
Disk /dev/sda: 500GB
Sector size (logical/physical): 512B/4096B
Partition Table: msdos

Number  Start   End    Size   Type     File system  Flags
 1      32.3kB  210MB  210MB  primary  ext4         boot
 2      210MB   500GB  500GB  primary               lvm


Warning: Unable to open /dev/fd0 read-write (Read-only file system).  /dev/fd0
has been opened read-only.
Error: /dev/fd0: unrecognised disk
 label                                 

Warning: Unable to open /dev/sr0 read-write (Read-only file system).  /dev/sr0
has been opened read-only.
Error: /dev/sr0: unrecognised disk label                                 

Error: /dev/zram0: unrecognised disk label                               

Warning: Unable to open /dev/cloop0 read-write (Read-only file system).  
/dev/cloop0 has been opened read-only.
Error: /dev/cloop0: unrecognised disk
 label                              

root at Microknoppix:/# gdisk -l /dev/sda
GPT fdisk (gdisk) version 0.8.5

Partition table scan:
  MBR: MBR only
  BSD: not present
  APM: not present
  GPT: not present


***************************************************************
Found invalid GPT and valid MBR; converting MBR to GPT format.
***************************************************************

Disk /dev/sda: 976773168 sectors, 465.8 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): E9B4E83E-86F3-4843-801E-495E6864F682
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 976773134
Partitions will be aligned on 8-sector boundaries
Total free space is 5099 sectors (2.5
 MiB)

Number  Start (sector)    End (sector)  Size       Code  Name
   1              63          409662   200.0 MiB   8300  Linux filesystem
   2          409663       976768064   465.6 GiB   8E00  Linux LVM
root at Microknoppix:/# vgchange -ay
  /dev/sda2: read failed after 0 of 1024 at 0: Input/output error
  /dev/sda2: read failed after 0 of 1024 at 4096: Input/output error
  /dev/sda2: read failed after 0 of 2048 at 0: Input/output error
  No volume groups found
root at Microknoppix:/# lvscan
  /dev/sda2: read failed after 0 of 1024 at 0: Input/output error
  /dev/sda2: read
 failed after 0 of 1024 at 4096: Input/output error
  /dev/sda2: read failed after 0 of 2048 at 0: Input/output error
  No volume groups found
root at Microknoppix:/# lvm lvdisplay
  /dev/sda2: read failed after 0 of 1024 at 0: Input/output error
  /dev/sda2: read failed after 0 of 1024 at 4096: Input/output error
  /dev/sda2: read failed after 0 of 2048 at 0: Input/output error
  No volume groups found
root at Microknoppix:/# vgscan --mknodes
  Reading all physical volumes.  This may take a while...
  /dev/sda2: read failed after 0 of 1024 at 0: Input/output error
  /dev/sda2: read failed after 0 of 1024 at 4096: Input/output error
  /dev/sda2: read failed after 0 of 2048 at 0: Input/output error
  No volume groups found
  No volume groups found
root at Microknoppix:/# 




More information about the linux-lvm mailing list