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• Support for RAID 0, 5, 6, and 10 disk arrays
• Additional features when the PCIe3 x8 cache SAS RAID internal adapter 6 Gb card is installed:

– Adapters support nonvolatile write cache
– Support for RAID 5T2, 6T2, and 10T2 tiered disk arrays (depending on the Operating System

support)

– Adapters configured in dual storage IOA or high availability (HA) RAID mode for best reliability

and availability

• RAID disk arrays supported as a boot device
• Advanced RAID features:

– Hot spares for RAID 5, 6, 10, 5T2, 6T2, and 10T2 disk arrays
– 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 (T10 Data Integrity Fields)

– Optimized hardware for RAID 5 and 6 sequential write workloads
– Optimized skip read/write disk support for transaction workloads

SAS architecture

Serial-attached SCSI (SAS) architecture describes a serial device interconnection and transportation

protocol that defines the rules for information exchange between devices.
SAS is an evolution of the parallel Small Computer System Interface (SCSI) device interface into a serial

point-to-point interface. SAS physical links are a set of four wires used as two differential signal pairs.

One differential signal transmits in one direction, while the other differential signal transmits in the

opposite direction. Data can be transmitted in both directions simultaneously. Physical links are

contained in SAS ports, which contain one or more physical links. If there is more than one physical link in

the port, the port is a wide port. If there is only one physical link in the port, it is a narrow port. A port is

identified by a unique SAS worldwide name (also called SAS address).
A SAS adapter contains one or more SAS ports. A path is a logical point-to-point link between a SAS

initiator port in the adapter and a SAS target port in the I/O device (for example, a disk). A connection is a

temporary association between an adapter and an I/O device through a path. A connection enables

communication to a device. The adapter can communicate to the I/O device over this connection by using

either the SCSI command set or the Advanced Technology Attachment (ATA) and Advanced Technology

Attachment Packet Interface (ATAPI) command set depending on the device type.
A SAS expander enables connections between an adapter port and multiple I/O device ports by routing

connections between the expander ports. Only a single connection through an expander can exist at a

time. Using expanders creates more nodes in the path from the adapter to the I/O device. If an I/O device

supports multiple ports, more than one path to the device can exist when the expander devices are

included in the path.
A SAS fabric refers to the summation of all paths between all SAS adapter ports and all I/O device ports in

the SAS subsystem including cables, enclosures, and expanders.

SAS subsystem for the 5105-22E, 9008-22L, 9009-22A, 9009-22G, 9009-41A, 9009-41G, 9009-42A,

9009-42G, 9223-22H, 9223-22S, 9223-42H, or 9223-42S 7