I think you are going to have to include a bit more information.
What does your setup look like? How many VM's per data store? Load on the ESX servers and NetApp? Log information? ONTap version?
What have you discovered so far? What have you tried? (How much money are you willing to pay to have it fixed? hehe)
No one is going to beg you to supply enough information. If you don't do it, you won't get help.