Issue while adding disks into VSAN disk group.

Today while trying to add disks to VSAN disk group I found that disks were showing in invalid status even they are not in used.

Then I took the putty session to ESX server and found that disks are having partition. 

I deleted partition after that I was able to add the disks in VSAN disk group. Here the partition number is 2 hence giving the 2 in command.