#DD BACKUP SYSTEMRESCUECD SERIAL NUMBERS#

#DD BACKUP SYSTEMRESCUECD SERIAL NUMBERS#

In order to determine which is the source disk, you can use smartmontools.Īnother way to determine drive serial numbers is with hdparm.Īnother useful way to check is to use ' fdisk -l'. Once booted ' fdisk -l' should show the two drives, perhaps /dev/sda and /dev/sdb. Reversing the order will zero out your critical source disk and the array will be lost. Getting the drive order correct is critical. The procedure is to record the drives serial numbers (you need to know which drive is the source and which the copy), connect both drives to the Linux host then boot from SystemRescueCD. The SystemRescueCD can be downloaded from:Īs of the iso is version 1.3.1 and is 238 MB in size. SystemRescueCd is a Linux system rescue disk available as a bootable CD-ROM or USB stick for administrating or repairing your system and includes all the needed tools.

Now some Linux distributions include ddrescue, but it is suggested to download and use SystemRescueCD. Since the DDF pointer is in the very last block of the disk, it's critical that disk copied to be the exact same size and geometry as the bad block disk, which means you must use the same drive make and model. This is not guaranteed to recover all data as some blocks will not be readable, but there is a potential that the bad blocks were not yet used for file storage. The basic process is to copy all readable blocks to another disk and using the copied disk to be rebuild the array. In this case, one possible solution is to use Linux ddrescue. In some cases a critical drive may have excessive bad blocks, causing a rebuild to appear hang. Often when one drive in an array fails, other drives in the array may also develop problems since all drives in the array are subject to the exact same wear and environment. Using ddrescue to recover a RAID disk with many bad blocks

Dd backup systemrescuecd