Montar LVM GNU/Linux y Reparar

• sudo su 
• instalamos lvm2 
• aptitude install lvm2 ó yum install lvm2
• fdisk -l (para verificar que existen lvm)
• pvscan (escaneo particiones lvm)
• vgscan (detectar grupos LVM)
• vgchange -a y (activa los LVM logicos para poder escanearlos)
• lvscan (para poder ver los volumenes logicos disponibles)
• crear una carpera en la cual montar el volumen logico.
• /mnt/volumen1 o /media/volumen1 según el sistema.

para un caso particular es importante que el sistema no monte en el arranque /dev/sales/reports ya que si esta corrupto no permitira autenticar en el sistema.

• Type root's password
• Edit the /etc/fstab file
• Comment out the line with /dev/sales/repor
• Reboot

Para verificar el estado de los volumenes y comprobar si tenemos errores  

• cat /proc/partition
• pvscan

si tenemos errores 

1. Fortunately, the meta data and file system on the disk that was /dev/sdc are intact.
2. So the recovery is to just put the disk back.
3. Reboot the server.
4. The /etc/init.d/boot.lvm start script will scan and activate the volume group at boot time.
5. Don't forget to uncomment the /dev/sales/reports device in the /etc/fstab file.

Otra forma de error LVM corrupto.

Solution 1:

1. Since the disk was never removed, leave it as is.
2. There were no device UUID errors, so don't attempt to restore the UUIDs.
3. This is a good candidate to just try restoring the LVM meta data.
4. Run a file system check on /dev/sales/reports. whit e2fsck /dev/sales/reports

si vgcfgrestore sales falla 

vgcfgrestore sales
  Couldn't find device with uuid '56ogEk-OzLS-cKBc-z9vJ-kP65-DUBI-hwZPSu'.
  Couldn't find all physical volumes for volume group sales.
  Restore failed.

1. Comparing the output of cat /proc/partitions and pvscan shows the missing device is /dev/sdc, andpvscan shows which UUID it needs for that device. So, copy and paste the UUID that pvscan shows for /dev/sdc.

ls-lvm:~ # pvcreate --uuid 56ogEk-OzLS-cKBc-z9vJ-kP65-DUBI-hwZPSu /dev/sdc
  Physical volume "/dev/sdc" successfully created

2. Restore the LVM meta data

ls-lvm:~ # vgcfgrestore sales
  Restored volume group sales

ls-lvm:~ # vgscan
  Reading all physical volumes.  This may take a while...
  Found volume group "sales" using metadata type lvm2

ls-lvm:~ # vgchange -ay sales
  1 logical volume(s) in volume group "sales" now active

3. Run a file system check on /dev/sales/reports.

ls-lvm:~ # e2fsck /dev/sales/reports
e2fsck 1.38 (30-Jun-2005)
/dev/sales/reports: clean, 961/131072 files, 257431/262144 blocks

ls-lvm:~ # mount /dev/sales/reports /sales/reports/

ls-lvm:~ # df -h /sales/reports
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/sales-reports
                     1008M  990M     0 100% /sales/reports

Tomado de

http://www.novell.com/coolsolutions/appnote/19386.html

http://hotfixed.net/2011/07/25/montar-particiones-lvm-desde-un-livecd/