3 Replies Latest reply on Oct 2, 2017 3:34 AM by Nick_Andreev

    Help understanding reclamation for thin provisioning

    supermanDan Novice

      Hi,

      Can some confirm or correct me on my understanding of potential areas that require disk reclamation in a vsphere environment?  Also have a few questions.  As far as I know, reclamation can happen at 2 levels:

      1. at the guest OS level when thin provisioned vmdk's are used

      2. at the esxi hypervisor level when the LUNs on the SAN are thin provisioned

       

      Further clarification For #1....This becomes necessary when space is allocated within the vm and then deleted withing the vm.  To reclaim this, it is required to have vm-hw version 11, EnableBlockDelete=1 on hosts, esxi 6, thin provisioned vmdks, and guest OS that is capable of recognizing thin disks.  But what guest OS's are capable?  I've read some articles saying that windows 2008+ are capable; others that only windows 2012 R2+.  What about Linux?  Lastly, is it required for esxi 6.0 to have CBT disabled?  What about 6.5?

       

      Further clarification on #2....This becomes necessary when a vm is storage vmotioned from one datastore to another or when snapshots are consolidated.  I know starting with esx 5.0 U1, this became a manual process to perform (vmkfstools or esxcli storage unmap)....is this still true as of esxi 6.0 and 6.5?

       

      Thanks in advance