reclaiming / compacting unused VMDK space for backup purposes

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Hi all! 


Can somebody help reducing/compacting a DSM VMDK file from 30G  to what it's really using (1TB) ? Should I've made a snapshot right after my DSM installed with my packages?


I want to make a full backup of my virtual xpenology guest VMware fusion machine (OSX host on a SSD). The thing is the xpenology is using approximately 1 gig MAX but , my VMDK size is about 30 GIG as of now... I must have use this space from previous downloaded files but deleted those afterward. My recycle bin in DSM is turned off and empty. The backup is mainly because I use this for many thing including a docker homebridge setup and some other things and I don't want to start over if my HD dies..


I've read that

1-BTRFS (and EXT4)  partition doesn't need to be "defragmented" like a ntfs partition for windows guest vm it seems. 

2- can't install VMware tools on DSM guest os

3- As I use a SSD I'm not convince about using a software that zero out all unused bites (unnecessary wear?)


thanks for your help!


EDIT: I've run the DSM volume defragmentation and no change on the VMDK file size. Volume is at 1.02 GB but VMDK file size still at 30Gb..

Edited by raidsm

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On 10/26/2019 at 9:11 AM, bearcat said:

What provisioning mode was used when you made the VMDK?

 I did not choosen the pre alocated option neither the  split into 2 gig when creating it.

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I am running into the same issue. Size of VMDK is around 75GB whereas the Xpenology thinks it is still 1GB. Disk space gained by removal of  files from Xpenology is not reflected in VMWorkstation Pro. 

Any ideas?

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If you used thick provisioning when installing this is the default VMware behaviour.

Ran into the exact problem when installing dsm with 1TB hdd thick provisioned.


I created another, smaller volume, added to the XPE and moved my files over and deleted the bigger one afterwards.


I did not use raid mode inside XPE as my NAS is already on a HW raid but from what I read you also just use a single drive.

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