In screenshot below, i first tried to clone with out creating destination folder. That resulted in error. After creating destination folder, vmkfstools command worked.
Creating VM using cloned disk
Login to VMware ESXi web interface. Create a new VM. On the step where you select hardware, delete existing Disk. Add a new disk, browse and select the newly created clone disk. In this case – “/vmfs/volumes/disk2/ubuntu-clone/ubuntu-clone.vmdk”
Once the VM creation is finished, you will be able to start the new VM. You can create a VM, then use it as template for creating new virtual machines.