This topic introduces and briefly defines some basic VTL terminology used throughout the QoreStor documentation.
|Library||A library is an emulation of a physical tape library and shares the same characteristics such as media changer, tape drives, and slots (cartridge slots).|
|Tape Drive||A Tape drive is a logical unit which is part of the emulated library. The media or cartridge is loaded in the Tape drives to be accessed by the Data Management application.|
|Tapes/Media/Cartridges||Tapes are represented as files and are units within the VTL where data is actually written. Tapes are loaded into a Tape Drive before being accessed.|
|Slots||Tapes are parked in Slots before they are retrieved by the data management application for access.|
QoreStor supports the following virtual tape library (VTL) tape access protocols.
The Network Data Management protocol (NDMP) is used to control data backup and recovery between primary and secondary storage in a network environment. For example, a NAS server (Filer) can talk to a tape drive for the purposes of a backup.
You can use the protocol with a centralized data management application (DMA) to back up data on file servers running on different platforms to tape drives or tape libraries located elsewhere within the network. The protocol separates the data path from the control path and minimizes demands on network resources. With NDMP, a network file server can communicate directly to a network-attached tape drive or virtual tape library (VTL) for backup or recovery.
The QoreStor VTL container type is designed to work seamlessly with the NDMP protocol.
iSCSI or Internet Small Computer System Interface is an Internet Protocol (IP)-based storage networking standard for storage subsystems. It is a carrier protocol for SCSI. SCSI commands are sent over IP networks by using iSCSI. It also facilitates data transfers over intranets and to manage storage over long distances. iSCSI can be used to transmit data over LANs or WANs.
In iSCSI, clients are called initiators and SCSI storage devices are targets. The protocol allows an initiator to send SCSI commands (CDBs) to the targets on remote servers. It is a storage area network (SAN) protocol, allowing organizations to consolidate storage into data center storage arrays while providing hosts (such as database and web servers) with the illusion of locally attached disks. Unlike traditional Fibre Channel, which requires different cabling, iSCSI can be run over long distances using existing network infrastructure.
iSCSI is a low-cost alternative to Fibre Channel, which requires dedicated infrastructure except in FCoE (Fibre Channel over Ethernet). Note that the performance of an iSCSI SAN deployment can be degraded if not operated on a dedicated network or subnet
The VTL container type is designed to work seamlessly with the iSCSI protocol. For details, see Creating a VTL type container .