topic Re: RAID 1 with different disk sizes in ProLiant Servers - Netservers

Raid 1 with different disk sizes

Jorge HP — Wed, 03 Dec 2008 16:35:13 GMT

Hello people,

Proliant ML150 G5, HP Embedded SATA RAID Controller (RAID 0,1,10), 2 SATA hard disk, of
160 and 250 Gb, is it possible to create a Raid1??,
HD 160 Gb in port 0, and HD 250 Gb in port 1???

thanks in advance

Re: Raid 1 with different disk sizes

Pieter 't Hart — Thu, 04 Dec 2008 07:44:47 GMT

In theory no problem.
Done this with SCSI
Not done it with SATA.

max size will be limited to 160G!!

Re: Raid 1 with different disk sizes

MSECO — Thu, 04 Dec 2008 14:11:07 GMT

Hi Jorge:

Please check the next document:

http://h20000.www2.hp.com/bc/docs/support/SupportManual/c00771065/c00771065.pdf

RAID 0

The size of a drive segment is the size of the smallest disk drive in the array. For instance, an array that consists
of two 250-GB disk drives and two 400-GB disk drives has a drive segment size of 250 GB. This array thus has
1,000 GB (= 4 x 250 GB) of usable drive space, all of which can be used to store data when the array is used
to build a RAID 0 logical drive. The array also has 300 GB of drive space that is unusable in the context of this
particular collection of drives.

RAID 1
If a RAID 1 array is built from different-sized disk drives, the size of the drive segment is the size of the
smaller disk drive, as with RAID 0.

Re: Raid 1 with different disk sizes

adnanmaliq — Fri, 29 May 2015 09:29:23 GMT

Hi Jorge
In above scenario is it possible to use the extra space left on bigger drive "300 GB of drive space that is unusable" ? If so then how ? and is it possbile to do it online(while system is running, using hpacucli etc) ?

My scenario :
Server : ProLiant BL460c Gen8
Model : HP Smart Array P220i Controller
Logical Drive 01 : 136 GB , Fault Tolerance : RAID 1/RAID 1+0
Physical Drive in Port 1I Box 1 Bay 1 --> Capacity: 136 GB,
Physical Drive in Port 1I Box 1 Bay 2 --> Capacity: 558 GB,

So i am getting 136 GB space in OS. How can I use the remaining space from physical disk 2 : Space : 558-136 =422GB
I want to use this 422GB. It might sound strange and I am aware of the fact that this part of the disk will not be using RAID 1.

I will really appreciate quick replies.

Adnan Malik

Re: RAID 1 with different disk sizes

Dennis Handly — Sat, 30 May 2015 02:28:39 GMT

>In above scenario is it possible to use the extra space left on bigger drive?

I don't think you can. The OS can't see that part unless the controller allows these "left over" pieces.

Re: RAID 1 with different disk sizes

adnanmaliq — Sat, 30 May 2015 20:48:12 GMT

" The OS can't see that part unless the controller allows these "left over" pieces."

and how to allow in controller ?

Re: RAID 1 with different disk sizes

Dennis Handly — Sat, 30 May 2015 20:58:40 GMT

>and how to allow in controller?

That's the problem, I don't think it can. Especially since this isn't a normal situation.

Re: RAID 1 with different disk sizes

Jimmy Vance — Sun, 31 May 2015 03:15:18 GMT

You can use any disk same size or larger than the smalles disk in the array. The array will only use whatever size the smallest disk in the array is. All 'extra' space is wasted and unusable. The only option is to change out all of the disks to the same size as the largest disk (one at a time). Once the array has rebuilt (between each disk swap) you can then expand the array to reclaim the unused space

Standard disclaimer:

Always have a good backup before you start messing around with your disks or arrays

Re: RAID 1 with different disk sizes

adnanmaliq — Mon, 01 Jun 2015 15:31:06 GMT

Yes i know that, But that does not answer my question :)

Adnan

Re: RAID 1 with different disk sizes

Jimmy Vance — Mon, 01 Jun 2015 15:37:06 GMT

@adnanmaliq wrote:
Yes i know that, But that does not answer my question :)

Adnan

My comment

"The array will only use whatever size the smallest disk in the array is. All 'extra' space is wasted and unusable" doesn't answer your question?

Re: RAID 1 with different disk sizes

adnanmaliq — Mon, 01 Jun 2015 22:13:05 GMT

>"The array will only use whatever size the smallest disk in the array is. All 'extra' space is wasted and unusable" doesn't answer your question?

Please excuse my earlier comment and allow me to re-phrase it. Your answer does answer my question but it does not resolve my problem of using that extra space. This is probably because it is not possible to use that extra space, as you and Dennis said already.
Thanks for the quick responses everyone.

Adnan

Re: Raid 1 with different disk sizes

new_learning — Fri, 08 Dec 2017 02:55:03 GMT

Hello all
i want to ask
now slot hardisk to server database full. for now running each slot 300gb this condition life (production). i want to replace to 1TB for slot 5 and 6. can this be done?

whether this will have an impact on the system or for example on slot 5 and slot 6 that previously 300gb hardisk space I replace to 1TB. can this be?

now a total of 6 slots (slot 1,2,3,4 permanent running per slot 300gb)
whether this will impact on raid conditions that run on the existing server ?
for conditions existing using raid 1 0