I have a server with Adaptec 2405 RAID card. I have 4 hard drives attached to it. I want to add 4 more. Adaptec site says 2405 can handle up to 128 hard drives with SAS expanders. It's not clear to me whether I need to buy separate SAS expander card to go with it, or SAS expander mentioned here is just another enclosure that has SAS expander port on it.
Do those enclosures have SAS expander cards on it such that I can just buy SFF-8088-to-SFF-8087 cable and hook it up? Or do I need another SAS expander card in my server? If so, what works well with my raid card?