VMware is easy if you have storage vmotion. Let VMware do the work for you.
Luns are straightforward going to cDOT using Foreign Lun Import (FLI). The cDOT cluster is inserted between the SAN host and the old storage during a brief cutover event, after which the LUNs are brought onlline and clients continue while Data ONTAP imports the luns. There are details to be considered but that would be my first stop.
For NFS data we have XCP https://xcp.netapp.com to bring 3rd party NFSv3 data into cDOT. Its really fast and its free. It doesn't do CIFS at this point, but there are other options ranging from commercial to robocopy depending on your scale and budget.
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