Properties of real tapes

• Real tapes have a large capacity and thus offer a simple way to increase the storage capacity in a data center, to relieve the load on the disk storage space, and to export large volumes of data for various purposes (e.g. data backup and archival);
• In addition to data transport via networks, as a transportable storage medium tapes permit flexible data storage at various locations. On the one hand, the data center is relieved of the data storage load and, on the other hand, backup and archive volumes can be stored in a protected location (e.g. in a fireproof archive). The tapes are easy to transport, and can be dispatched. Applications for tape transport include:
  • software installation (data is on tapes in compressed form and is installed on a system ready to run);
  • transporting large volumes of data that are not urgently needed;
  • transporting data with a high level of security which should not be exchanged through networks for that reason;
  • exporting data that is not frequently needed online to less expensive tapes (access time is not important).
• Each tape is managed in BS2000 and MAREN by means of its archive number (synonym: volume serial number, VSN). The archive number should be unique in the data center;
• BS2000 differentiates the various types of tape by means of the volume type. Tapes can only be processed by tape devices that support their specific volume type. The devices that process the various volume types are distinguished by BS2000 through the device type;
• A tape in BS2000 is logically accessed through DMS. Tape device allocation for processing a tape is controlled through the device management of the BS2000 system (NDM). Input and output requests are processed by the BS2000 device drivers;
• The operator is responsible for mounting the tapes in the appropriate tape devices, see section “Tape operator” (Manual operation of real tapes);