Best way to migrate luns from one NetApp array to another NetApp with minimal or no downtime

Hello,

I would like to move luns (presented to a windows 2008 server) from one NetApp FAS to another FAS. We have SQL databases runnign on it so would prefer online  migrations is possible. Can you suggest my options. 

I've used FLI to migrate from 3rd party to NetApp.

Thanks and appreciate your response.