IBM-IMSourcing DS - 44V8581

The PCI Express (PCIe) Dual - x4 3Gb SAS RAID Adapter supports the attachment of Serial attached SCSI (SAS) disk and SAS solid-state drives using a pair of mini SAS 4x connectors. The 5903 has a 380 MB write cache and a concurrently replaceable cache battery pack. The adapter must always be installed in pairs and is always to be used in a high availability, multi-initiator RAID configuration using two adapters in dual-controller mode. Two 5903 adapters provide mirrored write-cache data and mirrored RAID parity footprints between the adapters. If the 5903 pairing is broken, then write cache is disabled.

Important: See the following topics for more information and important considerations for multi-initiator and high availability configurations: SAS RAID controllers for AIX, SAS RAID controllers for IBM i, or SAS RAID controllers for Linux. See also Important partitioning considerations with dual-slot and multiadapter configurations.

The 5903 supports SAS small form factor (SFF) disk drives located in a PCIe 12X I/O Drawer or SAS disk drives located in an EXP 12S Disk Drawer. It can also be connected to the internal disk drives in the system unit using the appropriate split disk backplane feature and cabling.

The adapter is a 3.3 V, PCI-e x8 bootable SAS adapter that supports RAID levels 0, 5, 6, and 10. Some RAID level support is operating system dependent. The adapter provides RAID 0, RAID 5, RAID 6 and RAID 10 for the AIX® and Linux operating systems. Under the IBM® i operating system, mirroring and data spreading is provided by the operating system and RAID 5 and RAID 6 is provided by the adapter.

With proper cabling and configuration, multiple wide ports are used to provide redundant paths to each dual port SAS drive or solid-state drive. The adapter manages SAS path redundancy and path switching should a SAS failure occur.