I gather that you are talking about the NetApp integration into vCenter - because that is really the only place where I can remember that you need to enter credential for the Filer.
This does not affect your running VM's - because they are mounted on ESX hosts directly to the NetApp volumes (NFS I presume) and that is done without credentials.
Maish - VCP - vExpert 2010
VMware Communities User Moderator
Virtualization Architect & Systems Administrator
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