oracleasm createdisk and asmtool

Hi all,

   I want to ask about the difference between oracleasm createdisk and creating disk via asmtool.

   Before, I setup and created shared disk with name is DATA1 with

   usr/sbin/oracleasm createdisk DATA1 /dev/sdb1                                                          [1]

   Today, my colleague created shared disk by:

   /usr/sbin/asmtool -C -l /dev/oracleasm -n DATA1 -s /dev/sdb1 -a force=yes               [2]

   Ofcourse, I can saw disks via listdisks command from oracleasm.

   If you experience about it, please give me some comments !

   Thanks.

Regards,