Reclaim Disk Space for VMware vSphere 6.7U1 and later on vSAN datastores

This topic is relevant if you are using vSAN datastores. Prior to vSphere with vSAN 6.7U1, there is no space reclamation support. Starting with 6.7U1, vSAN space reclamation is supported with the vCenter Server UNMAP feature on vSAN datastores. It is deactivated by default.

Procedure

1. Check that the UNMAP feature is enabled in the ESXi host.
   Run the following commands from the command line:

   esxcfg-advcfg -g /VSAN/GuestUnmap

   The value of the "GuestUnmap" option is 0.

   esxcfg-advcfg -g /VSAN/Unmap

   The value of the "Unmap" option is 1.

2. Enable guest UNMAP in all ESXi hosts.
   Run the following command:

   esxcfg-advcfg -s 1 /VSAN/GuestUnmap

   Then, check the UNMAP feature for the guest operating system. Run the following command:

   esxcfg-advcfg -g /VSAN/GuestUnmap

   The value of the GuestUnmap option is 1.
3. Enable the UNMAP feature in vCenter Server.
   Run the following RVC command:

   vsan.unmap_support <cluster> -e