I have a question about a RAID hardware concent. We have an LSI Megaraid 9260-4i RAID controller. We would like to extend our RAID array but it has only 4 internal ports. It supports 32 SATA hard drives according to its properties. Could you please tell me how is it possible? Are there some kind of expanders available with which I can connect multiple drives to only one port? And is it available any perfomance drawbacks when multiple drivers are connected into only one port?
While GhislainG is mostly correct, I believe that it's not just a cable. You need a device called an "SAS Expander," or "Port Expander," which presents one SAS connection to the card and up to eight SAS connections for drives. These don't work with all SAS controllers; the controller has to support expanders, and your does.
The User's Guide, for example, states that "You can connect one device per SAS PHY unless you use an expander." (a PHY is a one physical connector)
Typically, these are implemented in an external drive rack that has four SAS or SATA connections which are then expanded to however many the device holds. It sounds to me like your drives are internal to your server, which means that you would have to find standalone internal expander cards. Does your chassis really have room for 32 drives? For a roll-your-own internal example, look at http://www.servethehome.com/sas-expanders-diy-cheap-low... .