IBM DS8000 Megabyte MB, Metro Mirror, Micro Channel architecture MCA, Migration, Mirrored pair

megabyte (MB)

1)For processor storage, real and virtual storage, and channel volume, 220 or 1 048 576 bytes.

2)For disk storage capacity and communications volume, 1 000 000 bytes.

Metro Mirror

A function of a storage server that maintains a consistent copy of a logical volume on the same storage server or on another storage server. All modifications that any attached host performs on the primary logical volume are also performed on the secondary logical volume. See also Remote Mirror and Copy and Global Copy.

MES See miscellaneous equipment specification.

MIB See management information base.

Micro Channel architecture (MCA)

The rules that define how subsystems and adapters use the Micro Channel bus in a computer. The architecture defines the services that each subsystem can or must provide.

Microsoft Internet Explorer (MSIE)

Web browser software manufactured by Microsoft.

migration

The replacement of a system or subsystem with a different type of system or subsystem, such as replacing a SCSI host adapter with a fibre-channel host adapter. In the context of data migration regarding the DS8000, the transfer of data from one storage unit to another, such as from a 3390 to the DS8000.

MIH See missing-interrupt handler.

mirrored pair

Two units that contain the same data. The system refers to them as one entity.

mirroring

In host systems, the process of writing the same data to two disk units within the same auxiliary storage pool at the same time.

miscellaneous equipment specification (MES) IBM field-installed change to a machine.

missing-interrupt handler (MIH)

An MVS and MVS/XA facility that tracks

I/O interrupts. MIH informs the operator and creates a record whenever an expected interrupt fails to occur before a specified elapsed time is exceeded.

MLC See machine level control.

mobile solutions terminal (MoST)

The mobile terminal used by service personnel.

mode conditioning patch cable

A cable that converts a single-mode signal from a longwave adapter into a light signal that is appropriate for multimode fibre.

Another mode conditioning patch cable is required at the terminating end of the multimode fibre to convert the signal back to a single-mode signal for a longwave adapter.

Model 100

A 2105 Model 100, often simply referred to as a Mod 100, is an expansion enclosure for the Enterprise Storage Server. See also 2105.

MoST See mobile solutions terminal. MRPD See machine reported product data. MSA See multiport serial adapter.

MSIE See Microsoft Internet Explorer. MTBF See mean time between failures.

Multipath Subsystem Device Driver

See IBM TotalStorage DS8000 Multipath Subsystem Device Driver.

multiple allegiance

A DS8000 hardware function that is independent of software support. This function enables multiple system images to concurrently access the same logical volume on the DS8000 as long as the system images are accessing different extents. See also extent and parallel access volumes.

Multiple Device Manager (MDM)

A component of the IBM TotalStorage Productivity Center that allows administrators to configure, manage, and monitor the performance of SAN storage devices from a single console.

multiple relationship FlashCopy

An option of the DS8000 that creates backup copies from one source to multiple

342IBM TotalStorage DS8000: Messages Reference