Solved

RAID Management query

Posted on 2011-03-16
12
333 Views
Last Modified: 2016-12-08
I have a server with a raid controller and 7 disks.

Each disk is 500 GB in size.

I want RAID 1 with 2 disks for OS. RAID 5 with 5 disks for data.

Problem is RAID 1 on 500 GB for solely OS is a waste. Can I somehow allocate 450 GB of the OS RAID 1 to the RAID 5?

In the DELL setup utlility it seems I have to use the entire 2 disks. Can I somehow manage this after the OS is installed?

I would like to see OS RAID 1 50 GB, DATA RAID 5 2 TB

Regards
0
Comment
Question by:Network_Padawan
  • 4
  • 3
  • 3
  • +2
12 Comments
 
LVL 9

Expert Comment

by:pcchiu
ID: 35152899
You can't do that as the hard drive physically in 500G.    

You can get 2x120GB hard drive for the OS and then save the 500GB for the RAID10 which may serve your purpose?

0
 
LVL 76

Assisted Solution

by:Alan Hardisty
Alan Hardisty earned 25 total points
ID: 35152903
With 500gb drives using 5 for RAID 5, you will have 2TB of data anyway, but the short answer is that you can't allocate the 450gb of space on the RAID 1 volume to the RAID 5 volume.

I would stick to a 500gb C: drive and enjoy the space!
0
 
LVL 9

Expert Comment

by:pcchiu
ID: 35152904
I also suggest using RAID 10 instead of RAID 5 if possible.
http://www.cyberciti.biz/tips/raid5-vs-raid-10-safety-performance.html

0
Netscaler Common Configuration How To guides

If you use NetScaler you will want to see these guides. The NetScaler How To Guides show administrators how to get NetScaler up and configured by providing instructions for common scenarios and some not so common ones.

 
LVL 32

Assisted Solution

by:PowerEdgeTech
PowerEdgeTech earned 70 total points
ID: 35152943
I too would recommend sticking with two drives for the OS - or getting two high-speed, smaller drives for the OS.

OR...

Your controller will also support multiple RAID 5's across the same set of disks, so you could create a RAID 5 of 50GB across all 7 disks, then use the remaining amount in another RAID 5.  This is called slicing.  This cannot be done in the Dell installation utility.  It must be set up in the CTRL-R configuration utility during POST, then skip that option during the installation utility (or skip the use of the utility altogether).  You would end up with a data "disk" in Windows that is larger than 2TB, so you would have to convert it to GPT before partitioning it.
0
 

Author Comment

by:Network_Padawan
ID: 35152952
Hi PowerEdge, I wasnt aware you could do slicing...will give that a try
0
 

Author Comment

by:Network_Padawan
ID: 35152990
pcchiu, why would i go for RAID 10? I stand to lose 500 GB with that setup
0
 
LVL 9

Assisted Solution

by:pcchiu
pcchiu earned 50 total points
ID: 35153065
I don't think you want to do slicing as if anything went wrong you may not able to recover any data, as RAID1 is the simplest raid and you can recover data and repair it easily.  With slicing in case anything went wrong it's make it much harder for recovery.

RAID 10 you gain on performance...  So if performance is more of the concern you may want to go for it, if the storage size is more important you can stick with RAID5..

0
 
LVL 32

Expert Comment

by:PowerEdgeTech
ID: 35153079
If you are using a Dell controller that will do RAID 5, it will also support slicing.

Which system/RAID controller are you using?

RAID 10 vs RAID 5 generally has better write performance (common for databases), and gives you "up to" two-drive fault tolerance (you can lose up to 2 drives and still have access to the data).  It does come at a disk/space cost though.
0
 
LVL 32

Expert Comment

by:PowerEdgeTech
ID: 35153127
Which is why I still recommend using two drives dedicated to the OS, but the controller can do it, if he is so-inclined to go that route.
0
 

Author Comment

by:Network_Padawan
ID: 35153157
Hi powers,

Its a perc 7 card I believe
0
 
LVL 47

Accepted Solution

by:
dlethe earned 105 total points
ID: 35153726
You really should just leave it alone BUT ...
Use the RAID1 for scratch table space; swap files; transaction logs; any write-intensive items.  Then not only do you accomplish "freeing up the space for data", but you also take advantage of the inherent write speed advantage of RAID1 over RAID5.

RAID10 is NOT going to be faster across the board, because on your O/S disk you're going to be doing a lot of 4KB I/Os.  If you so much as touch a file, and your stripe size in the RAID is 64KB, then you'll be forced to write 128KB worth of data every time.   RAID10 is better for a SQL database but not the boot drive, at least from the I/Os per second perspective.

Personally, I would leave things as they are.
0
 

Author Closing Comment

by:Network_Padawan
ID: 35177105
Thanks guys. Will just leave it as is.
0

Featured Post

NAS Cloud Backup Strategies

This article explains backup scenarios when using network storage. We review the so-called “3-2-1 strategy” and summarize the methods you can use to send NAS data to the cloud

Question has a verified solution.

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

The article will include the best Data Recovery Tools along with their Features, Capabilities, and their Download Links. Hope you’ll enjoy it and will choose the one as required by you.
In this article we will learn how to backup a VMware farm using Nakivo Backup & Replication. In this tutorial we will install the software on a Windows 2012 R2 Server.
This tutorial will walk an individual through locating and launching the BEUtility application and how to execute it on the appropriate database. Log onto the server running the Backup Exec database. In a larger environment, this would generally be …
This tutorial will give a short introduction and overview of Backup Exec 2012 and how to navigate and perform basic functions. Click on the Backup Exec button in the upper left corner. From here, are global settings for the application such as conne…

777 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