Solved

Storage virtualization

Posted on 2014-10-17
16
289 Views
Last Modified: 2014-10-17
We are getting Windows Server 2012 for the first time and we are looking at using Windows Storage Spaces for the first time.

We have never done virtualization and starting to learn about it. Our question is for example if you took two 500 GB drives, made them into a virtual disk and you were able to go up to a 2 TB virtual drive that is a volume and users can access it, can data be saved up to almost 2 TB on the volume?

How does the system add the other space if possible?
0
Comment
Question by:regsamp
  • 6
  • 6
  • 4
16 Comments
 
LVL 118
ID: 40386792
Two 500GB drives, is going to give you a maximum of 1TB of space.

It's a JBOD (just a bunch of disks), so depending upon mirroring, and DeDuplication, it's unlikely you will get 2TB of data on 1TB.
0
 

Author Comment

by:regsamp
ID: 40386806
Okay but we are trying to learn about virtualization and we are seeing videos of people increasing the storage size of disk drives with virtualization so ignoring the scenario above, how does the system add extra space and can you save data beyond the drive maximum? Below is a video of an example and it starts at 6:19.

0
 
LVL 118

Accepted Solution

by:
Andrew Hancock (VMware vExpert / EE MVE) earned 250 total points
ID: 40386851
DeDuplication and Compression.

Adding extra space, just add standard disks to the pool.

We currently have 10 virtual machines with virtual disk, which occupy 1.4TB in our storage pool.

Traditionally, this would take up 1.4TB of storage space.

This is deduplicated and compressed down to 348GB, and hence we have more storage available to store virtual machines. (and or standard data)
0
 

Author Comment

by:regsamp
ID: 40386861
Okay, thank you.
0
 
LVL 56

Assisted Solution

by:Cliff Galiher
Cliff Galiher earned 250 total points
ID: 40386876
You didn't actually post a link to a video. Storage virtualization does not change the rules of storage. You can only ever store as much data as you have physical space. To store more stuff, you either add more disks (something that storage virtualization technologies such as Storage spaces makes easier than RAID does), or you free up space through other means...such as the already mentioned dedup features. But dedup/compression is not required with storage spaces, nor does storage spaces automatically dedup. Dedup is not considered storage virtualization in any way and is an unrelated technology.

Now, again, because you didn't actually post a video link, I can only speculate on what you are seeing. But one other caveat to consider is yes, storage spaces supports a concept called "thin provisioning." This basically means I can claim to have more storage than I actually do. If you hit physical capacity, writes will still fail, even though you aren't yet at the size you claimed you have.

Think provisioning has a place in large environments and there are reasons you might deploy such a solution, but is a bad idea for most smaller organizations (which I am making an educated guess that this is for a smaller environment since most large organizations would also have virtualization experts already on staff.)
0
 

Author Comment

by:regsamp
ID: 40386919
This must be a problem with the link feature then because we have tried three times now and it won't post:
https://www.youtube.com/watch?v=CxH4ADPQX6s
0
 

Author Comment

by:regsamp
ID: 40386925
But what about this then? "This is deduplicated and compressed down to 348GB, and hence we have more storage available to store virtual machines. (and or standard data)"

"But one other caveat to consider is yes, storage spaces supports a concept called "thin provisioning." This basically means I can claim to have more storage than I actually do. If you hit physical capacity, writes will still fail, even though you aren't yet at the size you claimed you have."  

Then why would anyone want to do this??  It is at 6:19 in the video where it starts.
0
 
LVL 118
ID: 40386952
This is not Thin Provisioning.

This is DeDuped, so if we have 10 Copies of Windows 2012 in 10 VMs, we only actually need to store the OS data on 1 VM!

hence the saving!
0
Threat Intelligence Starter Resources

Integrating threat intelligence can be challenging, and not all companies are ready. These resources can help you build awareness and prepare for defense.

 
LVL 56

Expert Comment

by:Cliff Galiher
ID: 40386974
Actually, the video the OP linked to is about thin provisioning. The "thin or fixed" portion of the virtual disk is covered at around 8:20, not 6:19.

So yes, you can thin provision, and yes, that means you can hit a situation where your virtual disk is not yet "full" but your physical disks are. And writes will fail in this scenario.

-Cliff
0
 

Author Comment

by:regsamp
ID: 40386994
The video is listed as Windows Server 2012 Storage Spaces not as thin provision and the section I was referring to does start at 6:19 and as I indicated we are trying to learn about virtulization for the first time. Stating that something will just fail and not offering help giving a new person some education in technology that is new for them is not helpful.
0
 

Author Comment

by:regsamp
ID: 40386999
"This is not Thin Provisioning.

This is DeDuped, so if we have 10 Copies of Windows 2012 in 10 VMs, we only actually need to store the OS data on 1 VM!

hence the saving!"  

Thank you. We are just trying to learn more and go beyond our RAID 5 traditional setups so it seems deduplication or at least Storage Space 2012 is want we want to look more into with this Windows environment. We are a small company so this is new for us. Sorry for the confusion.
0
 
LVL 56

Expert Comment

by:Cliff Galiher
ID: 40387145
The video you linked to does *not* show dedup at all. I was giving the more specific time reference of 8:20 so that Andrew could see what you were referring to and eliminate any confusion in actually answering your question.

The video may not be labeled thin provisioning, but thin provisioning *is* a feature of Storage Spaces and the video does use thin-provisioned spaces.

As far as "saying something will fail" and not providing "help" ...I'm not sure what else you want me to do. If you thin-provision a disk (or if you follow the video guidance) and create a space that claims to have more space than the physical disks you have and then add more data than the physical disks will hold, it *will* fail. EVEN WITH DEDUP!!!  Dedup doesn't change how thin provisioning works. And dedup *DOES NOT HAPPEN IN REALTIME!*  

Sometimes the answer it "it will fail."  There is nothing to be done. There is no "help" to be provided. There is no "fix" as the system isn't broken. It is working as designed. If you choose to thin-provision and you write too much data, it will simply fail. Full stop. No change, no help, no nothing.

-Cliff
0
 
LVL 118
ID: 40387154
No problems, I was trying to explain how you might fit "2TB in 1TB"!
0
 
LVL 118
ID: 40387166
@Cliff My comment was about my posted comments, not the video! in response to the Authors post.

I did not see the video link posted until now!

I was going back to the how do we fit "2TB in 1TB"......DeDupe and Compression!
0
 
LVL 56

Expert Comment

by:Cliff Galiher
ID: 40387181
@Andrew: I figured, which is why I wanted to clarify. There was just a bit of miscommunication and since there was a video that, presumably, the OP may follow while setting up their environment, it is reasonable to see how they could get into an overprovisioned situation. I wanted to try and avoid that for them. I never thought you were saying otherwise in your posts, so I wanted to be very clear that the video does indeed show thin provisioning and that could be a problem if space is over-allocated, even with dedup.

-Cliff
0
 
LVL 118
ID: 40387232
@Cliff

 No problems!

Andy
0

Featured Post

New My Cloud Pro Series - organize everything!

With space to keep virtually everything, the My Cloud Pro Series offers your team the network storage to edit, save and share production files from anywhere with an internet connection. Compatible with both Mac and PC, you're able to protect your content regardless of OS.

Join & Write a Comment

Veeam Backup & Replication has added a new integration – Veeam Backup for Microsoft Office 365.  In this blog, we will discuss how you can benefit from Office 365 email backup with the Veeam’s new product and try to shed some light on the needs and …
Restoring deleted objects in Active Directory has been a standard feature in Active Directory for many years, yet some admins may not know what is available.
In this Micro Tutorial viewers will learn how to use Windows Server Backup to create full image of their system. Tutorial shows how to install Windows Server Backup Feature on Windows 2012R2 and how to configure scheduled Bare Metal Recovery backup.…
In this Micro Tutorial viewers will learn how to restore their server from Bare Metal Backup image created with Windows Server Backup feature. As an example Windows 2012R2 is used.

760 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

21 Experts available now in Live!

Get 1:1 Help Now