disk cage

A container for disk drives. Each disk cage supports eight disk packs (64 disks).

disk drive

Standard term for a disk-based nonvolatile storage medium. The DS8000 uses hard disk drives as the primary nonvolatile storage media to store host data.

disk drive module (DDM)

A field replaceable unit that consists of a single disk drive and its associated packaging.

disk drive module group See disk pack.

disk pack

A group of disk drive modules (DDMs) installed as a unit in a DDM bay.

disk group

A collection of 4 disk drives that are connected to the same pair of IBM Serial Storage adapters and can be used to create a RAID array. A disk group can be formatted as count key data or fixed block, and as RAID or non-RAID, or it can be left unformatted. A disk group is a logical assemblage of disk drives. Contrast with disk pack.

distributed file service (DFS)

A service that provides data access over IP networks.

DNS See domain name system. domain

1)That part of a computer network in which the data processing resources are under common control.

2)In TCP/IP, the naming system used in hierarchical networks.

3)A Copy Services server group, in other words, the set of clusters the user designates to be managed by a particular Copy Services server.

domain name system (DNS)

In TCP/IP, the server program that supplies name-to-address translation by mapping domain names to internet addresses. The address of a DNS server is the internet address of the server that hosts the DNS software for the network.

dotted decimal notation

A convention used to identify IP

addresses. The notation consists of four 8-bit numbers written in base 10. For example, 9.113.76.250 is an IP address that contains the octets 9, 113, 76, and 250.

drawer

A unit that contains multiple device drive modules and provides power, cooling, and related interconnection logic to make the device drive modules accessible to attached host systems.

drive 1) A peripheral device, especially one that has addressed storage media. See also disk drive module.

2)The mechanism used to seek, read, and write information on a storage medium.

DS8000

See IBM TotalStorage DS8000.

DS8000 Batch Configuration tool

A program that automatically configures a DS8000. The configuration is based on data that IBM service personnel enter into the program.

DS Storage Manager

See IBM TotalStorage DS Storage

Manager.

duplex

1)Regarding Copy Services, the state of a volume pair after Remote Mirror and Copy has completed the copy operation and the volume pair is synchronized.

2)In general, pertaining to a communication mode in which data can be sent and received at the same time.

dynamic sparing

The ability of a storage server to move data from a failing disk drive module (DDM) to a spare DDM while maintaining storage functions.

E

E10 The predecessor of the F10 model of the Enterprise Storage Server. See also F10.

E20 The predecessor of the F20 model of the Enterprise Storage Server. See also F20.

EBCDIC

See extended binary-coded decimal interchange code.

332IBM TotalStorage DS8000: Messages Reference

Page 352
Image 352
IBM DS8000 manual Disk cage, Disk drive module DDM, Disk drive module group See disk pack Disk pack, Disk group, Drawer