Offline: A SCSI disk drive is in a “offline” state if it is not present, if it is present but not powered on, or if it failed to operate properly and was “offline” by the controller. When the controller detects a failure on a disk, it “kills” that disk by changing its state to “offline.” An “offline” SCSI drive can also be present and powered on, but a SCSI drive in a “offline” state does not participate in any I/O activity; no commands are issued to dead drives.
Rebuild: A SCSI disk drive is in a “rebuild” state while it is in the process of being rebuilt. During this process, data is regenerated and written to the disk drive. This state is also referred to as
SCSI Interrupt Steering Logic (SISL)
Architecture that allows a RAID controller, such as AcceleRAID 150, 200 or 250, to implement RAID on a system
SDRAM
Synchronous Dynamic Random Access Memory, a form of dynamic random access memory (DRAM) that can be coordinated or synchronized to the clock speed of the computer.
Segment Size
See Cache Line Size.
Sequential I/O
A type of read and write operation where entire blocks of data are accessed one after another in sequence, as opposed to randomly.
Server
A computer program that provides and manages services to other computer programs on the same or other computers. The computer that a server program runs in is also frequently referred to as a server.
SES
SCSI Enclosure Services, a standard for SCSI access to services within an enclosure containing one or more SCSI devices. For disk drives, power supplies, cooling elements, and temperature sensors, the actions performed are the same as for
AcceleRAID 352 Installation Guide |