Dell PowerVault 110T LTO2 (Tape Drive) User Manual
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SCSI interface. See Small Computer Systems Interface.
SCSI log sense data. In response to inquiry from the server about the tape drive's error logs and counters, a packet of SCSI sense bytes which contains that information and
which is sent back to the server by the drive. Log sense data is used to diagnose problems, especially if the problems are intermittent.
second. One sixtieth of a minute.
sense data. Data that describes an I/O error. Sense data is presented to a server in response to a Sense I/O command.
server. A functional unit that provides services to one or more clients over a network. Examples include a file server, a print server, or a mail server. The IBM pSeries, IBM
iSeries, HP, and Sun are servers. Synonymous with host.
single-character display. Located at the front of the tape drive, an LED that presents an alphabetical or numeric code which represents a diagnostic or maintenance
function, error condition, or informational message.
sleep mode. A power-management function that causes the tape drive's electronics to automatically enter a low-power mode by which to conserve energy.
Small Computer Systems Interface (SCSI). A standard used by computer manufacturers for attaching peripheral devices (such as tape drives, hard disks, CD-ROM
players, printers, and scanners) to computers (servers). Pronounced "scuzzy." Variations of the SCSI interface provide for faster data transmission rates than standard serial
and parallel ports (up to 160 megabytes per second). The variations include:
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Fast/Wide SCSI: Uses a 16-bit bus, and supports data rates of up to 20 MBps.
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SCSI-1: Uses an 8-bit bus, and supports data rates of 4 MBps.
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SCSI-2: Same as SCSI-1, but uses a 50-pin connector instead of a 25-pin connector, and supports multiple devices.
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Ultra SCSI: Uses an 8- or 16-bit bus, and supports data rates of 20 or 40 MBps.
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Ultra2 SCSI: Uses an 8- or 16-bit bus and supports data rates of 40 or 80 MBps.
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Ultra3 SCSI: Uses a 16-bit bus and supports data rates of 80 or 160 MBps.
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Ultra160 SCSI: Uses a 16-bit bus and supports data rates of 160 MBps.
software. Programs, procedures, rules, and any associated documentation pertaining to the operation of a computer system.
speed matching. A technique used by the tape drive to dynamically adjust its native (uncompressed) data rate to the slower data rate of a server. Speed matching improves
system performance and reduces backhitch.
status light. Located at the front of the tape drive, an LED that can be green or amber, and (when lit) solid or flashing. The condition of the light represents the state of the
drive.
T
TapeAlert. A patented technology and ANSI standard that defines conditions and problems that are experienced by tape drives.
TapeAlert flags. Status and error messages that are generated by the TapeAlert utility and display on the server's console.
tape cartridge. A removable storage case that houses belt-driven magnetic tape that is wound on a supply reel and a takeup reel.
tape drive. A data-storage device that controls the movement of the magnetic tape in a tape cartridge. The drive houses the mechanism (drive head) that reads and writes
data to the tape. Its native data capacity is 100 GB per cartridge; with 2:1 compression, its capacity is up to 200 GB.
tape path. Within a tape drive, the channel in which the media moves.
terminate. To prevent unwanted electrical signal reflections by applying a device (known as a terminator) that absorbs the energy from the transmission line. terminator. (1)
A part that is used to end a SCSI bus.
(2) A single-port, 75-&Omega. device that is used to absorb energy from a transmission line. Terminators prevent energy from reflecting back into a cable plant by absorbing
the radio frequency signals. A terminator is usually shielded, which prevents unwanted signals from entering or valid signals from leaving the cable system.
Test Head diagnostic. A test that determines whether the heads of the tape drive are operating properly and whether the drive can correctly read from and write to tape.
transfer rate. See data transfer rate.
U
Ultra160 LVD SCSI interface. See Small Computer Systems Interface.
unload. The act (performed by the drive) of unthreading tape from the drive's internal tape path and returning it (with the leader block) to the tape cartridge.
utility. See utility program.
utility program. A computer program that supports computer processes. For example, a diagnostic program, a trace program, or a sort program.
V
Vdc. Volts dc (direct current).