Can this be done with RAID ?

[mikkydoos]

Hi all,

 

I'll be VM'ing our physical main file server soon - currently 12TB capacity over 8 disks on a RAID5 array.

 

I'll be putting extra hard disks in my host, creating a new array and a new datastore for that VM to fill up.

 

My hypervisor machine only has RAID0 and RAID1 on the controller.

 

HP HDD's for my server at the moment are:

 

4TB - £220

6TB - £770

 

 

If I create a RAID1 array can I make it larger than the capacity of the disk?

 

e.g. If I put in four 4TB disks can I make an array of 8TB?

 

 

Server is an HP Proliant 360p Gen 8 with the standard HP Smart Array P420i controller

 

 

I'm pretty sure I can't but I'm throwing it out there......

 

 

Cheers in advance

Edited February 17, 2017 by mikkydoos

[kmount]

If the controller supports RAID10 you can put your 4x4TB in and get the 8TB you're talking about yep. (the P420 looks like it does https://www.hpe.com/h20195/v2/GetPDF.aspx/c04111534.pdf )

 

Be careful moving from 8 disks down to 4, you might have a performance impact to factor in.

[Norphy]

Hi all,

 

I'll be VM'ing our physical main file server soon - currently 12TB capacity over 8 disks on a RAID5 array.

 

I'll be putting extra hard disks in my host, creating a new array and a new datastore for that VM to fill up.

 

My hypervisor machine only has RAID0 and RAID1 on the controller.

 

HP HDD's for my server at the moment are:

 

4TB - £220

6TB - £770

 

 

If I create a RAID1 array can I make it larger than the capacity of the disk?

 

e.g. If I put in four 4TB disks can I make an array of 8TB?

 

 

Server is an HP Proliant 360p Gen 8 with the standard HP Smart Array P420i controller

 

 

I'm pretty sure I can't but I'm throwing it out there......

 

 

Cheers in advance

 

No.

 

RAID 1 is mirroring. What you're describing there sounds more like RAID 10, a mirror of striped disks.

[bwestlake]

If you have two 4tb disks:

 

RAID1 - 4TB (Redundant)

RAID0 - 8TB (NON Redundant)

 

Is that what your asking?

[mikkydoos]

If you have two 4tb disks:

 

RAID1 - 4TB (Redundant)

RAID0 - 8TB (NON Redundant)

 

Is that what your asking?

 

No. I want to make a RAID1 array larger than the size of each single disk.

I think I need RAID 10.

 

 

 

If the controller supports RAID10 you can put your 4x4TB in and get the 8TB you're talking about yep. (the P420 looks like it does https://www.hpe.com/h20195/v2/GetPDF.aspx/c04111534.pdf )

 

Be careful moving from 8 disks down to 4, you might have a performance impact to factor in.

 

 

Didn't think of disk performance yet. Good point.

 

My onboard controller only has RAID0 and RAID1. I think I might need a new controller.

[kmount]

Are you sure it's only RAID0 and RAID1?

 

How many disks have you got plugged in right now? It might not show you RAID10 until you have 4 plugged in.

[mikkydoos]

Are you sure it's only RAID0 and RAID1?

 

How many disks have you got plugged in right now? It might not show you RAID10 until you have 4 plugged in.

 

I don't think so. I've only got 3 in at the moment. Two mirrored and a spare.

[PotNoodleTech]

I had to read that a couple of times to try and get exactly what you are asking. I think I understand now.

 

The answer is no. Assuming your raid controller explicitly only supports raid 0 or raid 1 - Classic Raid 1 only allows you to use two disks in a mirror.

 

To use multiple pairs of disks in raid 1 your controller needs to support a hybrid raid 1 mode - Raid 01 for two pairs of raid 1 mirror disks in a raid 0 stripe, or RAID 10 for two pairs of raid 0 stripes in a mirror.

 

Need to find out exactly what your controller supports - it may well support RAID10/01 in which case you can do what you need to do (all 4 disks to create one 8TB mirror)

[3s-gtech]

Without checking the quickspecs as I'm in a rush, the P420 should be able to do RAID 10 without breaking a sweat. We have G5 and G7 servers with their contemporary controllers fitted, all doing RAID 10.

[mikkydoos]

Must be the number of disks in it at present.

 

Some on the way.... lets see

[Oaktech]

Grabbed from the HPE spec sheet...

 

RAID Support

 

RAID 6, 60 (Advanced Data Guarding)

NOTE: RAID 6, 60 can be enabled with a minimum of 512 MB FBWC

RAID 5, 50 (Distributed Data Guarding)

NOTE: A minimum or 512 MB cache is required to enable RAID 5, 50 support of the Smart Array P420i

RAID 1, 10 (Drive Mirroring)

RAID 1 ADM, 10 ADM (Advanced Data Mirroring)

RAID 0 (Striping)

Edited March 2, 2017 by Oaktech

[PotNoodleTech]

Yes you look good to go then!

[supawat1]

I have HP ML380p Gen8 with P420i RAID Controller and for sure, it supports RAID10 and RAID 1. You can create multiple group of RAIDs 1, 5 and 10, the only limitation you have is the enclosure to hold HDDs.

[mikkydoos]

I have HP ML380p Gen8 with P420i RAID Controller and for sure, it supports RAID10 and RAID 1. You can create multiple group of RAIDs 1, 5 and 10, the only limitation you have is the enclosure to hold HDDs.

 

Great info. Thanks @supawat1

 

Looks like I'm good to go.

 

Thanks for the posts guys

[mikkydoos]

I have HP ML380p Gen8 with P420i RAID Controller and for sure, it supports RAID10 and RAID 1. You can create multiple group of RAIDs 1, 5 and 10, the only limitation you have is the enclosure to hold HDDs.

 

Great info. Thanks @supawat1

 

Looks like I'm good to go.

 

Thanks for the posts guys