Also, take a look at the new joint VMware/NetApp/CISCO Reference Architecture guide available on both NetApp and VMware sites, highlighting use of NetApp and VMware cloning capabilities to meet requirements for different user types in any environment.
Regarding the gold image / clones, many customers are using them to host 1000s of virtual desktops in production environment. They are reliable for personalized VMs and you only need space for the new writes, discounting the regular dedupe savings you will get. Regarding the patching and upgrading, if the desktops are personalized and users store data on the C drive, you'll have to patch each desktop individually. Othewise, if the desktops are not very personalized and the user data is on the CIFS share, you can upgrade the gold and redeploy VMs.
With 4-8 IOPS per desktop, you could use the FAS2050 for 1000 desktops. But definitely use the NetApp tools to do the environment analysis and determine the IOPS numbers for the customer. We have a joint Ref Arch with VMware that highlights the 1000 desktop scenario. Although this Ref Arch was 100% VMware Linked Clones, the architecture is also valid for NetApp FlexCone or mixed FlexClone/Linked Clone scenario.
Also FAS3170 is not a requirement for above 1000 desktops. Although TR3770 used FAS3170 for 2000 desktops, the architecture could easily be supported on a FAS3140 with 2 PAM cards.
Check out page 6 of the document above, we had 2 GigE links per filer on a FAS2050 for 500 users per filer and didn’t see any issues.
No the golden image is not mandatory for VDI. You could use VMware full cloning method. If you create the VMs using VMware full cloning, you would have to buy the storage upfront to create 500 full clones (or e.g. create 100 and then dedupe and then another create another 100 and so on…), adding to the cost, complexity and overall time required to provision VMs, specially if you plan to manage the VMs in a connection broker.