Solved

Replacing failed raid 1 with different speed drive

Posted on 2013-05-29
11
1,441 Views
Last Modified: 2016-12-08
Hi,
Hopefully this is fairly simple.

I have a HP DL380G5 with a  HP Smart Array P400 controller (doing this from memory, not at system).  I have the system drives in a Raid 1 configuration using 2-Seagate ST9146803SS drives.  It looks like one has failed.

I found a drive locally,  ST9146852SS, that seems to be the same other than the rotational speed (specs below).

Is it possible to have two drives in an array that are of different speeds?

Seagate ST9146803SS - Savvio 10K.3 146GB 10K 6.0Gbps SFF Serial SCSI / SAS Hard Drive

Seagate  ST9146852SS - Savvio  15K.2 146GB 15K 6.0Gbps SFF Serial SCSI / SAS Hard Drive

Thanks,
--SM
0
Comment
Question by:smantz
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 5
  • 2
  • 2
  • +2
11 Comments
 
LVL 88

Expert Comment

by:rindi
ID: 39204857
The different speed won't matter. You just won't get any advantage of the higher speed as long as you don't also change the other drive for one running at that higher speed too.
0
 
LVL 95

Expert Comment

by:John Hurst
ID: 39204860
I would be inclined to keep the two speeds the same, lest you run into some hardware synchronization issues that depend upon matched speeds. I do not know if this is the case, but I would not take the chance.  .... Thinkpads_User
0
 
LVL 47

Assisted Solution

by:dlethe
dlethe earned 200 total points
ID: 39204953
Actually you WILL get slight advantage with higher speed drive.  Every I/O on that disk will take less time than I/Os on the other disks.
0
Best Practices: Disaster Recovery Testing

Besides backup, any IT division should have a disaster recovery plan. You will find a few tips below relating to the development of such a plan and to what issues one should pay special attention in the course of backup planning.

 
LVL 55

Accepted Solution

by:
andyalder earned 300 total points
ID: 39205184
Agreed, fractional improvement with a faster disk. The controller does two types of load-balanced reads, if it is very busy it will split the reads between the two disks but if less busy it will send both disks for the data and take the first answer which is more likely to come from the fast disk.

Are you sure they are generic Seagate disks though and do not have HP's part numbers on them as well? HP load custom firmware on their disks with tweaked retry timeouts and slightly different capacity, generally smaller than the generic drive so that any other manufacturer's disk will also be large enough. If you upload an ADU report **as attachment** we can check what the controller sees it as. (ADU should be under Start-HP system tools if installed else it's under the ACU on the SmartStart CD)
0
 

Author Comment

by:smantz
ID: 39205843
Well I'll try and remote in and if I' can't, it will be tomorrow before I'm back on site.  But I'll upload whatever I can.
0
 

Author Comment

by:smantz
ID: 39205946
Here are the attachments from the ACU for the controller, hope they help.
-SM
ADUReport.txt
ADUReport.xml
ADUReportTransform.xsl
ADUReportViewer.htm
0
 

Author Comment

by:smantz
ID: 39206047
I do believe that these drives are generic as there weren't any drives when I received the unit.  If need be, I will  take the unit down and pull the drives to see if there is any HP numbers.
0
 
LVL 55

Expert Comment

by:andyalder
ID: 39206165
They are indeed generic drives from that report rather than HP branded ones so you are right to use a generic drive as replacement for now.
0
 

Author Comment

by:smantz
ID: 39206172
So you feel there really wouldn't be much of a risk trying and using this drive?
0
 
LVL 47

Expert Comment

by:dlethe
ID: 39206196
SAS drives are all enterprise class so are similar or potentially same quality disks.  There are a few minor firmware tweaks that HP makes, but what you have is good enough for RAID1.  Now if you were doing RAID5 with max config of disks then I would say just to buy HP.
0
 

Author Closing Comment

by:smantz
ID: 39206208
These guys are great and if I could give more points, I would!!!  Thanks a million
0

Featured Post

Report: Liquid Web beats Amazon, Rackspace & More

A study by performance analyst firm Cloud Spectator finds that Liquid Web beats rivals Amazon, Rackspace and DigitalOcean when it comes to website and cloud application performance.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

A Bare Metal Image backup allows for the restore of an entire system to a similar or dissimilar hardware. They are highly useful for migrations and disaster recovery. Bare Metal Image backups support Full and Incremental backups. Differential backup…
Data center, now-a-days, is referred as the home of all the advanced technologies. In-fact, most of the businesses are now establishing their entire organizational structure around the IT capabilities.
This tutorial will walk an individual through configuring a drive on a Windows Server 2008 to perform shadow copies in order to quickly recover deleted files and folders. Click on Start and then select Computer to view the available drives on the se…
This tutorial will walk an individual through the steps necessary to install and configure the Windows Server Backup Utility. Directly connect an external storage device such as a USB drive, or CD\DVD burner: If the device is a USB drive, ensure i…

734 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