Convert vmdk for using in ESXi

The vmdk file, e.g, created in vmware workstation, cannot be directlt used in ESXi. It needs to be converted. The process is:

1. Enable ssh connection in ESXi host.
2. ssh to ESXi host, e.g. ssh -l root 192.168.1.110
3. cd to the directory containing the vmdk file, e.g.
   cd /vmfs/volumes/62169753-c96da716/vmdk
4. Suppose the vmdk file is ubuntu.vmdk, and let the converted vmdk filename be ubuntu_convert.vmdk. Then issue the command,
   vmkfstools -i ubuntu.vmdk ubuntu_convert.vmdk -d thin
5. It will show something like:
   ...
   Clone: 100% done.
   It does not mean thee conversion is really finished. Just wait until the shell returns prompt, e.g. [root@chiao-dell:/vmfs/volumes/62169753-c96da716/vmdk]
6. Usually, it will take couple of hours to finish for large file, YES! H.O.U.R.S. !
7. If the datastore in on an nfs server, e.g. 192.168.1.8, then get into the nfs directory and use the following command to display the converted file size.
   ls -lsh ubunut_convert-flat.vmdk
   You will see something like this line:
   2.0G -rw------- 1 myuid mygid 510G  8月  8 16:27 ubuntu_convert-flat.vmdk
   Keep running this command, the size at the front is increasing.