• Server Chassis is Supermicro SuperStorage Server SSG-6027R-E1R12L http://www.supermicro.com/products/system/2U/6027/SSG-6027R-E1R12L.cfm
• Raid Controller is a single LSI 9240-8I
• Hard drive configuration is 12 WD2003FYYS 2TB 7200RPM drives
Only the LSI Controller is used. It is attached to the 12 bay back plane containing the 12 SATA drives using 1 SAS connector. All 12 drives are detected and run fine in RAID5. There are 2 virtual volumes, one 100GB and one consumes the rest of the available drive space. I am not seeing performance issues, but the server is not under any load.
So effectively only one of the 2 SAS ports are being used on the LSI controller to drive 12 SATA drives. This appears to be by design on the supermicro MB. The backplane only has one SAS connector. What I cannot find is where the server throughput bottleneck may be. The controller is designed for 8 drives at 6Gb/s transfer, so is it running at 150% capacity (4.5Gb/s) ? Or since only one SAS connecter is being used, is it running at 300% capacity (2Gb/s)?