IANAL so I skip licensing question. Single controller will protect against drive failure, but will not protect against controller failure (or any component inside controller). Normal FAS configuration consists of two controllers (HA pair). Also for disks you will need to have supply of spares when they start to fail.
if you are going to use clustered data ontap, then there is licesing requirements, that are only generated from netapp, don't think this will be easy, because the ownership of the controllers has changed.
if you are using 7-mode data ontap, then the only license for provisioning that comes included with a Zero costs is iscsi. Otherwise again you to contact netapp.
The above is for a single controller, anything else needs licensing to enable Failover, etc.
Thanks you both for your help... got a couple follow-up questions.
Couple Follow-up questions
1. Could you give me an idea on how much licensing costs are? I could probably get by with just having a single controller with no failover, but would like to know how expensive licensing is... I'm assuming licensing can not that expensive since the FAS3240 device is several grand.
2. I'm wondering if you can even get licensing for refurbished equipment.
3. If I wanted to go with single-controller 7-mode data ontap and the free iscsi license, will this be sufficient to hook up my FiberChannel Deskshelf and use Iscsi to connect to my vmware server?
First, that's wrong. Software package for FAS3200 came with one "free" protocol license of choice - this could have been iSCSI, but could also have been something else. But this absolutely does not matter in this case, because you are not buying anything from NetApp, so it does not matter whether NetApp was offering anything free or not. What matters technically is what license codes you got from your supplier. And I do not imply that you can legally use them! EULA that you must read and accept before you can download software includes "non-transferrable" clause. But again, IANAL so you are really better off contacting NetApp officially (which also answers your question about price of software). It is not something that can be settled in forum discussion.
Otherwise yes, you can use NetApp to host ESX datastores, using any of iSCSI, FCP or NFS protocol. It does not matter whether it is redundant HA pair or not; being non-redundant just restricts your ability to do maintenance work on it non-disruptively.