Solved

Rebuild at RAID5?

Posted on 2007-04-04
9
405 Views
Last Modified: 2013-11-14
In server with RAID 5 configuration, one of our harddisk is OFFLINE.
Does it mean harddisk failed, because we can make it ONLINE and it works, but it still no data when we check at Windows.
If we choose to REBUILD will it erase the datas?
0
Comment
Question by:isuhendro
  • 5
  • 4
9 Comments
 
LVL 27

Expert Comment

by:Nopius
ID: 18855542
> In server with RAID 5 configuration
You need to specify what kind of 'RAID5': hardware of software, then, if hardware, what vendor/device.

> Does it mean harddisk failed
Probably yes. Disk goes offline automatically when there are exessive errors in most RAID configurations.

> If we choose to REBUILD will it erase the datas?
If you rebuild RAID with 1 failed disk you loose data with high probabilty, regardless of what kind of RAID are you using.  Change disk first. Then tell us _where_ do you intend to do 'rebuild', in what program/utility (it depends on type of your raid).
0
 
LVL 27

Expert Comment

by:Nopius
ID: 18855544
One more note to "> Does it mean harddisk failed
Probably yes. Disk goes offline automatically when there are exessive errors in most RAID configurations."
If your disk failed your RAID should be in 'degraded' state. It might also be possible that disk doesn't belong to any RAID group and it may be just 'offline' itself.
0
 

Author Comment

by:isuhendro
ID: 18855634
Hi Nopius,

Thanks for your answer. It's hardware RAID5, HP NetServer.
0
 
LVL 27

Accepted Solution

by:
Nopius earned 125 total points
ID: 18855675
isuhendro, then  'REBUILD' is non destructive, but I recommend you to change drive to a good one first.
If you had configured spare and automatic rebuild before drave failure, then your array should be in 'good' state since all data already has been rebuild to spare. Then you need to change a drive.
If you had no spare or no auto rebuild, then just change a drive and start it manually.
More user documentation for all Netserver products is available from http://netserver.hp.com You may find your RAID installation/configuration manual there.
0
Google Storage: Standard vs. Nearline vs. Coldline

Google Cloud Storage has a number of classes to choose from. Although there are a lot in common, they vary in price and usage terms. This post explains Google Cloud Storage classes and helps to understand which  one to choose.

 

Author Comment

by:isuhendro
ID: 18855867
hi Nopius,

we've finished the rebuild, all 4 harddisk are online now.. but still at Windows - Disk Management detect "Unknown" partition. Does it mean the data is gone? Is there any other way?

Thanks & regards.
0
 
LVL 27

Assisted Solution

by:Nopius
Nopius earned 125 total points
ID: 18855909
> but still at Windows - Disk Management detect "Unknown" partition.
Do you mean it was 'Unknown' _before_ you started rebuild? If yes, than nothing changed, really... It should stay exactly the same as before.
It's possible that you have had double disk failure in raid5 _before_, then yes, your data is gone. Also it's possible that your partition table was corrupted with or without this failed disk. This issue is also indepentant of any raid configuration and then yes, your data is gone.

You may try to recover data (even from dead partitions) with any data recovery software that supports SCSI devices and your partition type (I guess NTFS). I may advice RTT R-STUDIO Data Recovery Software: http://www.r-studio.com/. It has a 'demo' version and you may try it if it's able to find files on your disk. It costs $50 for full version.
0
 

Author Comment

by:isuhendro
ID: 18856211
hi Nopius,

it's true that before rebuild it was 'Unknown'.

now i'm trying to download r-studio. just wonder whether HP NetRaid Assistant also can do this kind of data recovery?
0
 

Author Comment

by:isuhendro
ID: 18864826
Hi Nopius,

You're most helpful.

Thanks & regards.
0
 
LVL 27

Expert Comment

by:Nopius
ID: 18869262
isuhendro do you have any success with recovering data or everything is lost?
0

Featured Post

Get up to 2TB FREE CLOUD per backup license!

An exclusive Black Friday offer just for Expert Exchange audience! Buy any of our top-rated backup solutions & get up to 2TB free cloud per system! Perform local & cloud backup in the same step, and restore instantly—anytime, anywhere. Grab this deal now before it disappears!

Join & Write a Comment

How to update Firmware and Bios in Dell Equalogic PS6000 Arrays and Hard Disks firmware update.
Moving your enterprise fax infrastructure from in-house fax machines and servers to the cloud makes sense — from both an efficiency and productivity standpoint. But does migrating to a cloud fax solution mean you will no longer be able to send or re…
This tutorial will walk an individual through the process of installing the necessary services and then configuring a Windows Server 2012 system as an iSCSI target. To install the necessary roles, go to Server Manager, and select Add Roles and Featu…
This Micro Tutorial will teach you how to reformat your flash drive. Sometimes your flash drive may have issues carrying files so this will completely restore it to manufacturing settings. Make sure to backup all files before reformatting. This w…

707 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

12 Experts available now in Live!

Get 1:1 Help Now