General information
This section provides general information about the IBM® SAS RAID controllers for Linux.
The controllers have the following features:
- PCI-X 266 system interface or PCI Express (PCIe) system interface.
- Physical link speed of 3 Gb per second serial-attached SCSI (SAS) supporting transfer rates of 300 MB per second on PCI-X and PCIe controllers.
- Physical link speed of 6 Gb per second SAS supporting transfer rates of 600 MB per second on PCI Express 2.0 (PCIe2) controllers.
- Supports SAS devices and non-disk Serial Advanced Technology Attachment (SATA) devices.
- Optimized for SAS disk configurations which utilize dual paths thru dual expanders for redundancy and reliability.
- Controller managed path redundancy and path switching for multiported SAS devices.
- Embedded PowerPC® RISC processor, hardware XOR DMA engine, and hardware Finite Field Multiplier (FFM) DMA Engine (for Redundant Array of Independent Disks (RAID) 6).
- Supports nonvolatile write cache for RAID disk arrays on some adapters.
- Support for RAID 0, 5, 6, 10, 5T2, 6T2, and 10T2 disk arrays.
- Supports attachment of other devices such as non-RAID disks, tape, and optical devices.
- RAID disk arrays and non-RAID devices supported as a bootable device.
- Advanced RAID features:
- Hot spares for RAID 5, 6, 10, 5T2, 6T2, and 10T2 disk arrays
- Ability to increase the capacity of an existing RAID 5 or 6 disk array by adding disks
- Background parity checking
- Background data scrubbing
- Disks formatted to 528 or 4224 bytes per sector, providing cyclical redundancy checking (CRC) and logically bad block checking on PCI-X and PCIe controller
- Disks formatted to 528 or 4224 bytes per sector, providing SCSI T10 standardized data integrity fields along with logically bad block checking on PCIe2 controllers
- Optimized hardware for RAID 5 and 6 sequential write workloads
- Optimized skip read/write disk support for transaction workloads
- Support for a maximum of 240 advanced function disks
with a total device support maximum of 1023 on PCIe2 controllersNote: The number of all physical SAS and SATA devices plus the number of logical RAID disk arrays must be less than 1023 per controller.
- Supports a maximum of 64 advanced function disks with a total device support maximum of 255 (the number of all physical SAS and SATA devices plus the number of logical RAID disk arrays must be less than 255 per controller).
Note: This information refers to various hardware and software features
and functions. The realization of these features and functions depends
on the limitations of your hardware and software. The Linux operating system supports all functions
mentioned. If you are using another operating system, consult the
appropriate documentation for that operating system regarding support
for the mentioned features and functions.