Karthick -
Not if you've got HA set up correctly. You can do a non disruptive upgrade.
See the 'Upgrade Adviser' feature of MyASUP on the mysupport.netapp.com site.
I hope this response has been helpful to you.
At your service,
Eugene E. Kashpureff, Sr.
Independent NetApp Consultant, K&H Research http://www.linkedin.com/in/eugenekashpureff
Senior NetApp Instructor, IT Learning Solutions http://sg.itls.asia/netapp
(P.S. I appreciate points for helpful or correct answers.)