Dot Hill Systems 200 devices and servers providing accelerated data access, Scsi, SCSI address

	devices and servers providing accelerated data access.
SCA	Single connector attachment. A SCSI disk connector technology coinvented by Sun
	Microsystems. The SCA provides all SCSI, power, and control signals in a single
	connector, and enables easy servicing and highly reliable, pluggable disk drives.
SCSI	Small Computer Systems Interface. An industry standard for connecting disk and tape
	devices to a workstation.
SCSI address	The octal representation of the unique address (0-7) assigned to a narrow device; or hex
	representation of the unique address (0-15) assigned to a wide SCSI device.
SES	SCSI Enclosure Services driver. An interface to SCSI Enclosure Services devices. These
	devices sense and monitor the physical conditions within an enclosure, as well as enable
	access to the status reporting and configuration features of the enclosure (such as indicator
	LEDs on the enclosure).
SID	Primary controller identifier number
simplex	Transmission in one preassigned direction only. See also full-duplex and half-duplex.
SMTP	Simple Mail Transfer Protocol. A protocol for sending e-mail messages between servers
	and from mail clients to mail servers. The messages can then be retrieved with an e-mail
	client using either POP or IMAP.
SNMP	Simple Network Management Protocol. A set of protocols for managing complex
	networks. SNMP works by sending messages, called protocol data units (PDUs), to
	different parts of a network. SNMP-compliant devices, called agents, store data about
	themselves in Management Information Bases (MIBs) and return this data to the SNMP
	requesters.
spanning	Disk spanning makes use of the firmware's striping capability to stripe data across two
	otherwise independent RAID logical drives. The two spanned logical drives are presented
	to the operating environment as one logical drive. The advantages of spanning are: --
	Supports two simultaneous drive failures in the combined fault tolerant logical drives
	(provided there is one drive failure from each logical drive). -- Improves performance
	because the number of spindles is increased. The disadvantage of spanning is that the
	RAID overhead for redundant RAID levels is increased since each logical drive handles
	fault tolerance separately.
split channel	Inside the same drive array enclosure, when the drive channel is evenly divided into two
	separate channels; for example, when a 12-drive channel is cleaved into two independent
	channels
standby drive	A drive that is marked as a spare to support automatic data rebuilding after a physical
	drive associated with a logical drive fails. For a standby drive to take the place of another
	drive, it must be at least equal in size to the failed drive and all of the logical drives
	dependent on the failed disk must be redundant.
state	The current operational status of a disk drive, a logical drive, or redundant controllers. The
	array stores the states of drives, logical drives, and redundant controllers in its nonvolatile
	memory. This information is retained across array power interruptions.
stripe sizestriping	This is the amount of data in kilobytes that is striped across each physical drive in a
	logical drive. The values are in increments of 8 kilobytes and range from 8 to 64 kilobytes.
	Generally, large stripe sizes are more effective for arrays with primarily sequential reads.
	To change the stripe size on an existing drive, you need to back up your data, redefine the
	stripe size, reconfigure the storage, and restore all the data. The storing of sequential
	blocks of incoming data on all the different SCSI drives in a logical drive. For example, if
	there are three SCSI drives in a logical drive, data will be stored as follows: block 1 on
	SCSI drive 1; block 2 on SCSI drive 2; block 3 on SCSI drive 3; block 4 on SCSI drive 1;
	block 5 on SCSI drive 2, etc. This method of writing data increases the disk array
	throughput because multiple drives are working simultaneously, retrieving and storing.
	RAID 0, 3, 5 or 1+ 0 all use striping.
striping	Spreading, or interleaving, logically contiguous blocks of data across multiple					i t th
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