Four Aces -
From the igroup command man page:
igroup rename existing_group_name new_group_name
Rename an existing initiator group. The rename operation will not impact access to LUNs that are mapped to the initiator group being modified.
If you rename the server iqn you can add to the igroup, then delete the old iqn after rename.
I hope this response has been helpful to you.
At your service,
Eugene E. Kashpureff, Sr.
Independent NetApp Consultant http://www.linkedin.com/in/eugenekashpureff
Senior NetApp Instructor, Fast Lane US http://www.fastlaneus.com/
(P.S. I appreciate 'kudos' on any helpful posts.)