Is it possible to Clone individual drives in a 3ware array instead of destroying the array and starting over?
3ware drive cloning is possible and can be done using several methods from any modern Linux boot up CD/USB jump drive and can be an alternative to destroying and recreating an array especially in cases where there are 24 2TB drives and backup is not feasible.
Knoppix 6.2.1 or a higher version is recommended for the ease of use and built-in 3ware support for most 9650/9690 and earlier models.
Knoppix makes working with Linux low level utilities for Windows users without much Linux experience possible.
It is highly recommended before continuing to read and heed the warnings and to make sure that you have secured a good set of 3ware DCB files from dumpall that have been approved by an LSI support Engineer.
***If you are cloning from a small drive to a larger disk, you must run dumpall and a repair script to move the 3ware information to the end of the larger disk must be generated***
See
3ware Inoperable array / dumpall
Cloning outline:
There are several methods and examples of raw disk to disk copy found at:
Comparison of disk cloning software - Wikipedia, the free encyclopedia
Be sure that the copy program you select can copy Raw track to track or bit for bit.
Compression, bad block truncation or OS file system copy will not work properly.
Basic dd clone for copying from 1 drive to another drive of identical size:
dd if=/dev/sdb of=/dev/sdc bs=4k conv=noerror
The above command is good for copying from 1 same geometry drive to another with some error handling capabilities such as an unrecoverable block.
There are more aggressive methods of disk copy and are slower but recommended.
Clone with retry is a good way to get data off of a drive when it is overheated, out of calibration or beginning to “Click” or reset.
Trinity Rescue
www.trinityhome.org
ddrescue -v /dev/sdx /dev/sdx rescued.log
ddrescue -r 1 /dev/sdx /dev/sdx rescued.log
x is the source and target, see explanation below of the typical Linux SCSI disk enumeration.
There are other features that are useful for drives that are having problems which make ddrescue more preferable.
ddrescue when using the log file can start from the point where it left off in lockup or disk timeouts.
This can be invaluable for disks that might be having PCB level problems such as a failing disk controller chip.
General practices and warnings:
*** DO NOT OVERWRITE YOUR SOURCE DRIVE***
Know your drive mapping!
This can be done easily with HDParm.
Systematically poll SCSI devices such as sda, sdb, sdc until you have found your source and target drives.
hdparm -i /dev/sda
You should see the following output:
Model Number: SAMSUNG SV2002H
Serial Number: 0395J1FR904324
Firmware Revision: RA100-04
Note the serial # and match the drive to the /dev/sda relationship.
Be methodical when moving drives in and out of an array:
Use a dry eraser or stickers.
The more you organize drives and cables, the less chance for mistakes.
Typical disk array organization examples are:
Take the disk on port x and label it "portx, slot x" (See 3ware BIOS for actual port # or trace cabling).
Write down the serial numbers of each disk on a separate piece of paper and cross reference them to the port for reference.
Tips:
***Backup array config data with Dumpall *** See Dumpall link below.
***Document your source and target serial numbers.
***Jumper your drive to SATA 1.5
Cloning from an old disk to a new disk of a higher capacity:
If you are cloning from small drive to large, that is acceptable but you must get the array information first with dumpall and consult your LSI technician or support engineer before moving disks.
Dumpall is 3ware’s config data collection utility.
Dumpall will allow you to save drive stripe and array mode data to files along with their corresponding disk serial numbers and other important log information so make sure that all files are gathered, zipped up, and redundantly stored.
Resources:
You will need a Linux Live CD recommend Knoppix Adriane 6.2.1 or greater as it has most SATA drivers commonly built into the motherboard and is easy to use
Place your new drive on the onboard controller and boot Knoppix.
Links for programs referenced in this article:
DDRescue
Trinity Rescue Kit: Download
Index of /pub/gnu/ddrescue
Ddrescue - Forensics Wiki
Knoppix Adriane Live CD
www.knoppix.org
Dumpall:
3ware Inoperable array / dumpall
USB DOS boot creation needed for Dumpall:
GoCoding.Com
TrueImage
Backup software for data backup and disaster recovery in Windows and Linux - Acronis
Für SMART Werte kann ich allen smartmontools oder eben gsmartcontrol (ist smartmontools mit gui) empfehlen. HDSentinel ist schön, wenn man die Werte auch via web angezeigt bekommen möchte. (siehe FNBalu)
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