This KB describes how to convert a Lazy Zeroed disk to Eagerly on Vmware. You should check these steps to apply converting operation.
Step 1:Check where Vmware stored on ESX servers.
On vSphere client click vmware machine and “summary”. In general information you ‘ll get ESX Host name which vmware machine stored.
Step 2:Connect and logon ESX server which you determined at step 1:
-you can use putty and any other tool which used to connect SSH.
Step 3:Check disk location that you need to convert.
-You can get this information from vSphere Client under resource tab.Check volume names.
Step 4:Connect ESX server and start operation
#ls /vmfs/volumes -Redirect under the volumes which disk is located.
#cd /vmfs/volumes/XPAR_VOL2_R522/ -Select Vmware machine
#cd /vmfs/volumes/XPAR_VOL2_R522/testVmwareServer -Start operation for vmdk file.Disk name for vmdk can be change . In this example I try to convert OS disk. So maybe you also need to check your disk vmdk name.
#vmkfstools -k 3DSECDBt00.vmdkEagerly zeroing: 3% done.