I want to migrate Celerra FS to Isilon kindly advice on best migration tool

Just to begin the discussion these nearly free tools are very useful in all NAS data copy situations:

CIFS/SMB: robocopy, EM Copy (EMC exclusive)

NFS: rsync

General (Windows/Linux/Mac): Beyond Compare 4 from Scooter Software ($50/license)

More information about the complexity of your environment would help generate better recommendations.

Regards,

Mike Horgan

I would suggest to ask in the Isilon section what tool Isilon prefers

you didnt even mention if the data is NFS, CIFS or multi-protocol