Storage for Dummies Question OES11

Hi

Storage is not my thing so this may seem like a stoopid question.

I have an OES11 server with a single FC card that connects to a FC switch that then has 4 paths to the SAN. When the server boots it sees the existing NSS volumes 4 times and won't mount them - is this a config issue at the server end or the switch? Is this where I would have to setup Multipathing? Though from what I've read, when talking about multipathing, it's multiple FC cards in the server talking to the storage controller.

If we disable 3 paths all is fine, though understandably slow.

Thanks in advance for any advice

Emily