What is the best way to shrink a thin provisioned disk. For those who do not have storage vmotion, you still can shrink the thin provisioned disk but it requires downtime. Shrinking thinprovisioned vmware disks in windows like linux, windows does not automatically zero blocks after deleting files. Storage chargeback is based on high watermark deleted space not reclaimed properly. Then, in hyperv manager, right click on the virtual machine and choose the settings command from the shortcut menu. When a vm is provisioned, the admin can create a thick or thin disk.
Storage reclamation part 2 windows kalles playground. When you have some vms with thin provisioned disks, you may have noticed that these will continue to grow, and never shrink. Free up esxi local drive vmfs datastore space after deleting data in a thin provisioned windows vm. This occurs with thinprovisioned virtual disk drives. With vmware being the market leader do they not just have this feature builtin and automatic.
Once the space has been filled with zeros you can shrink the partition as required. Reclaim deleted space on san from thin provisioned lun with. Ive been using his various utilities for nearly 20. Free up esxi local drive vmfs datastore space after. Thin provisioned virtual disks are quick to create and useful for saving storage space. Zero out, deflate, or whatever you want to call it. Not only do they allow overprovisioning, but with the prevalence of flash storage, performance degradation really isnt a concern like it used to be.
For example, if you create a new thinprovisioned 30gb virtual disk and copy 10 gb of files to it, the size of the resulting vmdk file will be 10 gb, whereas you would have a 30gb vmdk file if you had chosen to use a thickprovisioned disk. In this example we have a thin provisioned vmdk file with the size of 8 gb, which is the size of the disk as it appears to the virtual machine, in this case a windows 2003 server. Im only talking about shrinking thinprovisioned disks. Guest reclaim reclaims dead space from ntfs volumes hosted on a thin provisioned scsi disk. Defragmentation, sdelete, zeroing virtual disk veeam. Reclaim deleted space on san from thin provisioned lun. A similar technique can be used to shrink thinprovisioned guest hard disks. In case of fragmented disks, a single file may scatter all across the disk, so updating this file makes many block dirty while incremental changes are picked up with 1mb block, so even if a single bit in the block changes, the whole block is picked up during the incremental pass. When you have some vms with thin provisioned disks, you may have noticed. Vadims kb virtual machine preparation windows windows does not. Zero free space using sdelete to shrink thin provisioned. Before we can use vmkfstools to shrink the vmdk file we must zero out any unused space on the thin provisioned disk. Nov 05, 2012 the storage gets used only when needed by an application. The space in windows got used up a while back, so the vmdk is really.
Sdelete is a command line utility that takes a number of options. This feature is a great space saving technique, but rick vanover says its not worth the effort to. Dec 24, 2016 how to shrink a thin provisioned virtual disk vmdk thin provisioned disks are a great feature to save capacity as you virtual machines filesystem will never use the full capacity. I first prepared the disk with sdelete c and sdelete z. The shrink option is unavailable if the disk is thin provisioned. You can also use the shrink disk from vmware tools to reclaim the delete space. The users cleaned up about 8 tb, so windows now has 8 tb free. How to shrink a vmdk using vmware converter techrepublic. Please note that i dont want to focus on reclaiming space from underlaying luns. What happened is that i have a vm running centoscpanel and the vmdk had 500gb thin provisioned disk.
Below is an image which show what you will get in your shrink page of vmware tools if you are using thin provisioned disk. Thin provisioned disks are a great feature to save capacity as you virtual machines. This commandline tool has a powerful feature which can track and zero unused blocks. Vmware states you need to vmotion the disk to a datastore of a seperate block size first before this can take place though.
Shrink thin provisioned vmdk solutions experts exchange. Reclaiming thin disk space with storage vmotion and sdelete. Download sdelete onto the vm you want to shrink and run the following command, replacing drive. Nov 26, 2015 in disk management inside the guest, rightclick on the volume or partition at the end of the disk and click shrink volume. Windows will inform you the maximum amount it can shrink the disk by. In case of a unixoide os linux, freebsd, solaris, use dd. If it is not listed as a thin provisioned volume, talk to your storage admin. This overallocation is a key benefit of thin provisioning. May 06, 2017 thin provisioned disks never shrink automatically when you delete data from it, lets learn how to do it. What youll want to keep in mind that sdelete performs the cleanup against the entire os volume so it is io intensive. Using thin provisioned virtual disks can provide many benefits. Choose an amount that you wish to actually shrink it by and click shrink.
This will discard all unused space instead of defragmenting. This is required to reclaim space back from the virtual disk. Nov 09, 2015 free up esxi local drive vmfs datastore space after deleting data in a thin provisioned windows vm. After cleaning up the vm itself and running sdelete, its time to shrink the vmdk.
Running sdelete will increase the size of the thin provisioned disk to its maximum size. Oct 25, 2005 the shrink takes place over two distinct phases shrink preparation happens within guest os and shrink phase happens outside the os. Reclaim disk space from thin provisioned disks rickard nobel. I do not know a single system where you do not have at least 10gb of free space for os disks. On windows you can use sdelete or the following command on linux. The document solution to reclaim the free space also in the vmfs is fill the free blocks in the guest os with zeroed on windows can be done with sdelete and on linux with dd and then use a storage migration cold or hot with storage vmotion to move the vm file from one datastore to another. While thin provisioning adds storage as needed, it does not work in reverse, removing unneeded storage for the vm. Aug 15, 2012 sdelete deletes existing files and erases any file data that exists in the unallocated portions of a disk including files that you have already deleted or encrypted. We have a storage challenge in our organization, and i intend to reduce the storage space assigned to the vm. Open up windows defrag and make sure the drive is listed as a thin provisioned volume there.
That is the reason behind me not using it in this post. A simple way of doing this is by using a free utility called sdelete from sysinternals. Feb 21, 2011 now run sdelete against the disk that youre trying to reclaim the disk space from with the following command. Now, select the virtual hard disk that you want to compact, and click the edit. Reclaiming disk space with storage vmotion and thin provisioning. So first zero out the deleted space with sdelete and then use storage vmotion to convert the disk to thin. Now run sdelete against the disk that youre trying to reclaim the disk space from with the following command.
Dec 05, 2011 the document solution to reclaim the free space also in the vmfs is fill the free blocks in the guest os with zeroed on windows can be done with sdelete and on linux with dd and then use a storage migration cold or hot with storage vmotion to move the vm file from one datastore to another. In any given use, it allows you to delete one or more files andor directories, or to cleanse the free space on a logical disk. Vmware esx 4 reclaiming thin provisioned disk unused space. Free up esxi local drive vmfs datastore space after deleting. To shrink a vmdk we can use an esx command line tool vmkfstools, but first you have to zero out any free space on your thin provisioned disk. But often, data is written on a thinprovisioned drive and then deleted. Shrinking virtual disks and automating shrink with the. Dont waste time reclaiming space on thin provisioned vms. Thin provisioning space reclamation avoiding sdelete. To be able to zero the free space of the target disks on your windows virtual machine, you need to download sdelete a free utility from the microsofts sysinternals suite and unzip the files from the downloaded archive to c. The issue is that the server has been rebooted and the backup ran on the local disk. Zero free space using sdelete to shrink thin provisioned vmdk 050920 by myles gray 22 comments some things should be simple, shrinking a thin provisioned virtual disk should be one of them, its not. Zero free space using sdelete to shrink thin provisioned vmdk.
To shrink a thinprovisioned vmdk the guest filesystem has to be zeroed out. Its true that the shrink option can be used for this as well as long as the disk is already thick provisioned. The tool can also reclaim space from full disks and partitions, thereby wiping off the file systems on it. I used sdelete z to zero out the drives which increases the used storage to the full size of the disks but now when i run vmkfstools k on the vmdk files it completes but they do not get any smaller and i am stuck with a server that is consuming almost 1tb on disk when it only has about 100gb of data on its drives. This feature is a great space saving technique, but rick vanover says its not worth the effort to constantly reclaim space.
Ive tried the sdelete followed by the vmfstools comments, no luck. Windows does not automatically zero deleted blocks. Regardless if your vmdk is thin or thick, if i recall correctly the svmotion is still required to get your blocks back. To reclaim space you need to fill all unallocated space with zeros. Nov 24, 2014 ive tried this on a server i want to shrink in size.
Vmware vmdk shrink and storage thin provisioning 101. In disk management inside the guest, rightclick on the volume or partition at the end of the disk and click shrink volume. This can happen at the windows os level, rather than at the hardware level. Microsoft provides a tool that can zero blocks after while deleting a file or zero out the entire free space.
The process will be to sdelete z the drive first, then set the datamover to the old legacy datamover and storgage vmotion the disk to reclaim. This occurs with thin provisioned virtual disk drives. If youve cleaned up space on a thin provisioned disk and want to reclaim it then you need to use sdelete. Many storage arrays such as hps 3par line, datacore, and others have the ability to thin provision storage. How to shrink a thin provisioned virtual disk vmdk thin provisioned disks are a great feature to save capacity as you virtual machines filesystem will never use the full capacity. Shrink a thinprovisioned vmdk if youve thinprovisioned a vmdk under esxi and need to reduce it for whatever reason, the official vmware documentation suggest to migrate the vm to another datastore using vmware converter which is not always practical, thankfully an alternative exists. Regardless if your vmdk is thin or thick, if i recall correctly the svmotion. Nov 07, 20 before we can use vmkfstools to shrink the vmdk file we must zero out any unused space on the thin provisioned disk. More information can be seen here storage vmotion and moving to a thin provisioned disk. So sdelete z is recommended to be used with thin disks to reclaim white space after removing data to shrink the disk. Inside the guest vm we can see that the used space are about 1. Thinprovisioned virtual disks are quick to create and useful for saving storage space.
If you delete files from within the vm wanting to gain the space back, it just dont work. But i have a large vmdk that is 16tb, it was thin provisioned. Sdelete will basically put zeros in the blocks and can expand your thin provisioned drive to the max amount. So for optimizing migrations to thin provisioned disks either use sdelete by microsoftsysinternals or use the shrink option within vmware tools. The space in windows got used up a while back, so the vmdk is really close to 16tb. The system will determine how much the the volume can shrink. The storage gets used only when needed by an application. Aug 01, 2011 vsphere 4 introduced thin provisioning of virtual machine disk files. Now sdelete has finished, we need to run vmkfstools on the datastore to shrink the thin provisioned vmdk back down to size. Vmware also has the ability to thin provision virtual disks vmdk files. Power off the virtual machine, or disconnect the virtual disk you want to shrink. Apr 26, 2014 guest reclaim reclaims dead space from ntfs volumes hosted on a thin provisioned scsi disk. Jul 31, 2015 windows will inform you the maximum amount it can shrink the disk by.
The shrink takes place over two distinct phases shrink preparation happens within guest os and shrink phase happens outside the os. Sometimes you need to shrink a thin provisioned vmdk file after a lot of. Reclaim disk space from thin provisioned vmdk files in esx. Reclaim disk space from thin provisioned vmdk files in esx dec 12 2014 by lunarg at black manticore. On windows guests we can use the sysinternals tool sdelete replace the drive. Reclaim disk space from thin provisioned vmdk files in esxi server.
Reclaiming thin provisioned storage on windows using sdelete. Reclaiming disk space with storage vmotion and thin. Windows will start the shrinking process and it might take some time and appear to be hanging as windows will actually be defragmenting the disk in order to consolidate the free space towards the end of. Thinprovisioned virtual disks sdelete alternative to. How to shrink a thin provisioned virtual disk vmdk. Make sure you have space to accommodate this on your volumes. As the tool deals with active data, please take all precautionary measures understanding the scsi unmap framework and backing up important data.
Both work fine, but keep in mind they can be time consuming. Reclaim disk space from thin provisioned vmdk files in esx by lunarg on december 12th 2014, at 12. How to zero free space to shrink a thin provisioned vmdk. But often, data is written on a thin provisioned drive and then deleted. Dear data storage experts, we are using a san attached thinprovisioned lun on physical windows machine from a storage vendor. Thick provisioning allots a set quantity of storage for that vm, while thin provisioning only allocates storage space to a vm over time when it is actually required. With sdelete, you can also overwrite the contents of free space on your disk.
When you work with a thin disk provisionned vm, you are copying new files into a vm, then deleting them, again and again, this process grow the thin disks over time. If not, you can svmotion the vmdk and set the target as thin. Then you can release the zeroed space by running on the host and with the vm powered off the vmkfstools command. Sdelete deletes existing files and erases any file data that exists in the unallocated portions of a disk including files that you have already deleted or encrypted. Stack overflow for teams is a private, secure spot for you and your coworkers to find and share information. Tool to reclaim spaceshrink thin provisioned disks. Will thinprovisioned vms shrink automatically just as they would grow automatically. How long this takes depends on disk activity and your hardware.
Is there a tool to automatically reclaim the space on thin provisioned disks. I have a vm assigned about 2tb thin provisioned of disk space and it utilizes just about 300gb. Shrinking does require sp4 on windows 2000 to work without errors, there is a work around for those running sp3 or older. For example, if you create a new thin provisioned 30gb virtual disk and copy 10 gb of files to it, the size of the resulting vmdk file will be 10 gb, whereas you would have a 30gb vmdk file if you had chosen to use a thick provisioned disk. The amount of space used on the vms is less than the vmdk file size. Ive tried this on a server i want to shrink in size.
It was using only 100gb and i had a backup mount as nfs to my storage. Sdelete accepts wild card characters as part of the directory or file specifier. The sdelete alone from sysinternals is not going to shrink thin disks. I have shrunk the space on the server itself windows, but vsphere does not allow reducing the size of disk assigned to a vm. Howto shrink a thin provisioned virtual disk vmdk vadims kb. I am looking on how to shrink a vm so the vmdk is only the size it really uses. How to reclaim storage space from hyperv virtual machines. An alternative to sdelete for recovering space for thinprovisioned virtual disk is perfectdisks. Nothing is happening after giving the vmkfstool command. Nov 25, 2009 one more note before it comes up by my readers, vmware tools shrinking functionality is not support on thin provisioned disks.
609 1066 209 261 1333 904 1173 1170 1114 412 1191 389 230 1407 87 52 1655 1198 343 944 617 1024 417 728 644 1379 1147 96 999 79 231 1115 346