Solved

The purpose of Vmware Thin Disk

Posted on 2016-10-23
8
58 Views
Last Modified: 2016-10-23
If I understand when you create VM with Thin disk you allocate a disk size , for instance 40GB.
I have read that the actual size of the disk is based on the size of the Data written to disk on demand up to the size of 40GB that has been allocated.

If the VM will never use the Whole 40GB , let 's say it will use 15 GB, then the rest of the space (25GB) will never be used by other VMs, since its already allocated.. ?

OR I misunderstood the concept of Thin Disk

Probably, the 40GB is the limit that the Thin Disk can use..and in the mean time if other VMs use all the space on the Datastore where that VM (that has thin disk) on, then the VM will not get to 40GB of usage..since the space could have been used by other VMs ?

any clarification  ?

Thank you
0
Comment
Question by:jskfan
  • 3
  • 3
  • 2
8 Comments
 
LVL 68

Accepted Solution

by:
Qlemo earned 280 total points
ID: 41856049
"Allocated" doesn't really fit with Thin  Provisioning. Your 40 GB are only allocated if you really use them by filling up the disk with 40 GB of data. And once you did that, it remains at 40 GB, even if you delete all files.

Thin Provisioned disks may extend to the size you provided, but will only be as large as needed. The "free", unallocated space can be used by other VMs. So you can buld up 10 VMs with 500 GB thin p. disks on a 500 GB partition, as long as you do not really make use of the virtual disk space. If one of the VMs fills up its disk, others won't be able to allocate more space, and fail (i.e usually crash in some way).
0
 

Author Comment

by:jskfan
ID: 41856099
when you create new VM and assign a size to the disk (I guess it is called provisioning).
well if the Vm has used 15gb out of 40GB, and all other VMs in the same datastore run out of space and need more.
Will they be able to use the 25GB left from not being used by the VM you created ?
0
 
LVL 68

Expert Comment

by:Qlemo
ID: 41856108
Yes. The 40 GB is used for overall calculation of over-provisioning (which is reasonable to a certain extend, depending on the requirements), but is not "reserved" in any way.
0
 

Author Comment

by:jskfan
ID: 41856114
Means other VMs can use space  of the VM that has Thin Disk, if it has not been used yet by the VM, and other VMs need that space........Correct ?
0
Ransomware-A Revenue Bonanza for Service Providers

Ransomware – malware that gets on your customers’ computers, encrypts their data, and extorts a hefty ransom for the decryption keys – is a surging new threat.  The purpose of this eBook is to educate the reader about ransomware attacks.

 
LVL 118

Assisted Solution

by:Andrew Hancock (VMware vExpert / EE MVE)
Andrew Hancock (VMware vExpert / EE MVE) earned 220 total points
ID: 41856125
Correct, but be careful, because if you overprovision and allocate more space in Thin disks, than space you have on the datastore, and ALL VMs demand that space....

the VMs will fail.

It means, that you have to be overally careful, when using thin disks, and ensuring you manage and document space requirements carefully.
0
 
LVL 68

Expert Comment

by:Qlemo
ID: 41856207
https:#a41856049 should be pretty clear about that.
0
 

Author Closing Comment

by:jskfan
ID: 41856251
Thank you for you explanation Guys
0
 
LVL 118
ID: 41856264
No problems, just be careful if you use them, and manage and document them correctly, and keep an eye in and use reporting tools.

Overprovision is a big problem when using Thin disks, also some applications do not support them, e.g. Exchange.
0

Featured Post

PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

Question has a verified solution.

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

In this article, I show you step by step with screenshots to assist you - HOW TO: Deploy and Install the VMware vCenter Server Appliance 6.5 (VCSA 6.5), with some helpful tips along the way.
In this article, I will show you HOW TO: Perform a Physical to Virtual (P2V) Conversion the easy way from a computer backup (image).
How to install and configure Citrix XenApp 6.5 - Part 1. In this video tutorial we have explained step by step installation of Citrix XenApp 6.5 Server on Windows Server 2008 R2 is explained in this video. We have explained the difference between…
In this video tutorial I show you the main steps to install and configure  a VMware ESXi6.0 server. The video has my comments as text on the screen and you can pause anytime when needed. Hope this will be helpful. Verify that your hardware and BIO…

920 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

16 Experts available now in Live!

Get 1:1 Help Now