Data Storage Terminology for Dummies

Autoloader: a data storage device containing one tape drive, tape cartridge slots and a mechanical device that automatically loads and removes tapes from the drive(s), usually used for backup/restore.

Automation: the techniques and equipment used to achieve automatic operation or control, i.e., replacing human activity with a mechanical solution.

Backup: the act of deliberately collecting data, creating a viable copy of it, and storing it where it is both safe and easily retrieved.

Backup process: the guidelines or schedules by which backup operations occur.

Backup software: a software application that specifically aids in automating the collection and writing of data to a backup device, as well as the restoration of data from the backup device to its place of origin.

Backup window: the time during which a backup is scheduled to take place, usually during non-working or off-peak hours when impact to network users will be minimal.

Capacity: the measure of data that can be stored on a device.

Compression (compressed): encoding data to take up less storage space on magnetic tape. Compression is carried out in the server (software compression) or in the drive itself (hardware compression). Software compression speed is dependent on computer processor power, whereas hardware compression gives optimum performance and is transparent to the user. Data transfer speed and total tape capacity are affected by the data compression achieved.

Data: digital information

Data protection: the act of reducing risk to data loss or corruption.

DDS/DAT (Digital Audio Tape): A magnetic tape technology for backing up data using helical scan recording. DAT uses 4mm or 8mm cartridges that look like small audiocassettes and conform to the DDS (Digital Data Storage) standard. With capacity points of 72, 160, or 320GB per tape (compressed), DAT is popular in the workstation, PC and small server environments .

Disaster recovery: a plan by which backed-up data can be restored after a catastrophic event.

DLT (Digital Linear Tape): a linear tape technology designed specifically to store for backup/restore and archival applications.

Full backup: a backup operation that copies all available data from network-attached sources (servers, PCs, drives and drive arrays).

GB: gigabyte; a unit of computer memory or data storage capacity equal to one billion bytes (1000 megabytes).

Host Bus Adapter (HBA): a hardware device, typically a plug-in card, used for the interface between a server and network or other device (such as an autoloader).

Incremental backup: a backup operation that detects and collects only data that has been created or changed since the previous backup

Independent Software Vendor (ISV): software companies that create products to be used with hardware devices from various manufacturers. (e.g., Symantec, Computer Associates)

LTO (Linear Tape Open): a linear tape technology designed for data storage applications such as backup/restore and archive. Currently at Generation 6, LTO-6 is the highest capacity available with 2.5TB Native and 6.25TB compressed on a single LTO-6 cartridge.  LTO-7 and LTO-8 are in the works, with BaFe Barium Ferrite Technology.

Magazine: removable container with multiple slots for holding tape cartridges for easy transportability or off-site storage.

Mail Slot: opening in the autoloader where tape cartridges can be removed and inserted into the autoloader without turning it off or interrupting operation.

Mean Time Between Failure (MTBF): a statistical reliability measurement expressing the expected life of a device before service or replacement is required.

Off-site: a term used to describe the removal of backup tapes from the premises where they were created to provide a geographical safeguard against loss or damage.

Picker: robotic mechanism for capturing a tape and moving it within the autoloader.

Restore, restoration: to replace lost or damaged data with a copy found on a backup tape or tapes.

SAS: Serial Attached SCSI, the most advanced and highest-performance version of the SCSI interface.

SCSI: Small Computer System Interface; used for connecting peripheral devices, such as autoloaders, to computers or servers.

Standalone tape drive: a single tape drive that is not part of an automated solution.

Storage: a place where data resides; example: server or computer hard drive, CD-ROM, DVD, magnetic tape.

Tape drive: the device that writes and reads data to and from a magnetic tape.

Tape cartridge: the container housing tape, spindle(s), and sometimes-embedded computer chips, such as with LTO.

Transfer rate (data transfer rate): a measurement of tape drive performance that quantifies how quickly data can be read or written by a tape drive.

Verify: an operation performed by backup software that ensures a viable copy of specified data has been recorded by the backup device.