you did test this first ???? I would have thought you would have installed a storage virtualisation product with your sql servers safely shut down. I don't know anything about this product but a SAN is no different to any other network and if you start messing around with the switches you'll lose connectivity. You should check if this software is certified for use with SQL Server - a properly set up SAN is great but it doesn't take much induced latency to screw things up big time.

I'd raise a call with the vendors.