We have an old 2GFC SAN storage array (EMC) and needed to buy an HBA to connect a new server. The HBA’s from our vendor were listed as 4GFC, so I had to check on backward compatibility. Thanks to wikipedia, I found this:
“Products based on the 1GFC, 2GFC, 4GFC, 8GFC and 16GFC standards should be interoperable and backward compatible.” http://en.wikipedia.org/wiki/Fibre_Channel
There were also cards listed as “SW” (short-wave) which seems to be a fibre-channel way of saying “multi-mode” and “short-range”. The long-wave cards support very long distances and use single-mode fiber.
A 4GFC SW card will meet our 2GFC multi-mode needs nicely :-). Now just need to check the vmware hardware compatibility list for driver support.