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HP Hitachi Dynamic Link Manager Software User Manual

Page 640

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C. Glossary

618

D

Dev

A logical division of an LU that HDLM controls and operates. A Dev is equivalent to

a slice or a partition in Solaris.
In Solaris, each LU can be divided into more than one Dev.
Each Dev has a Dev number.
Depending on the access method, Devs are classified into the following two types:

block devices and character devices.
(See also: Dev number)

Dev number

In UNIX, a device number usually indicates a combination of the major device number

and minor device number. In HDLM, however, a device number has the following

meaning: a Dev number that is displayed in the

DNum

field.

A number (from 0 to 7 in ascending order) is assigned to each Dev in an LU. In Solaris

it is called the slice number.
No corresponding Dev number is allocated, because HDLM manages Devs per LU.
(See also: Dev)

dynamic reconfiguration

A reconfiguration that enables HDLM to recognize an HDLM device whose

configuration has been changed, without restarting the host.

E

emulation type

An LU type that is accessible from a host. Because an HDLM host is an open-system

host such as a PC or a UNIX computer, the HDLM host can access only the LUs that

have open-system emulation types.
For details on emulation types supported by a storage system, see the maintenance

manual for that particular storage system.

F

failback

A function for placing the status of a path recovered from an error into the Online

status, and then switching the access path to the path that was just recovered.