I believe you're referring to the 10GigE ports on the database servers. These are ethernet ports, not fiber channel. It may be possible to access a V7000 file module using NFS over Ethernet, though I haven't actually seen it done with V7000-type storage before.
Yes there are 2 10GB ethernet ports.
With Exadata you can choose two copper ports or two optical ports to run you client network (aka Oracle Net) on.
During the initial Exadata deployment a bond will be configured based on your decision.
Normally no other protocol then sqlnet is allowed to run on this IP.