xsan

Although connecting only to ethernet might be possible, this would only give you access to file metadata, and not provide actual file contents transfer, which is the purpose of the fibre-channel.
The hardware connections might need 1 or 2 ethernet connections in addition to the fibre-channel connection
Download this file (http://manuals.info.apple.com/en/xsan/XsanGettingStarted.pdf) which can give you a lot of basic information about what is needed for an xSan setup.