Device addresses

Mnemonic and unit ID

In BS2000 devices are identified and addressed by means of their mnemonic name. The mnemonic name is known as mnemonic for short and abbreviated to MN (in BS2000 output sometimes also abbreviated with MNEM).

Example

On the BS2000 console an emulated tape drive with the mnemonic AF is addressed in the /SHOW-DEVICE-STATUS and /ATTACH-DEVICE commands:

/SHOW-DEVICE-STATUS AF
%  MNEM DEV-TYPE CONF-STATE POOL VSN   DEV-A    PHASE    ACTION  
%  AF   BM1662FS DETACHED    SW         FREE            NO ACTION
/ATTACH-DEVICE AF
% MSG-000.165608  %  NKR0042 'DEVICE     =AF': ATTACH ACCEPTED
%XAAE-000.165608  %  NKR0116 ASSIGN FOR 'DEVICE=AF' IN PROCESS
% MSG-000.165608  %  NKR0110 'DEVICE     =AF' ATTACHED AND ASSIGNED
! UCO-000.165608  %  NBR0740 COMMAND COMPLETED 'ATTACH-DEVICE'; (RESULT: 
SC2=000, SC1=000, MC=CMD0001); DATE: 2017-01-09
/SHOW-DEVICE-STATUS AF
+XAAD MNEM DEV-TYPE CONF-STATE POOL VSN   DEV-A    PHASE    ACTION
+XAAD AF   BM1662FS ATTACHED    SW         FREE            NO ACTION

Tape drive AF is initially in the DETACHED status (CONF-STATE); it is then successfully attached using the /ATTACH-DEVICE command. The second command, /SHOW-DEVICE-STATUS, shows the new status.

With the exception of "normal" disks and real tape devices, the devices visible to BS2000 on an SU /390 are emulated devices and not directly the real devices. The disks for the emergency system are emulated at the MU. On SU x86, all devices visible for BS2000 are emulated. The following designation is more precise then "emulated devices": BS2000 emulations of the real devices.

The device address must be specified when an emulated device is configured for BS2000. The names in X2000/M2000 for the channel path identifier and logical unit number (LUN) are Host Connector and Unit ID, with Unit ID corresponding to the host LUN.

BS2000	Device address X2000 / M2000	Device address SU /390 (IORSF)	Device address Periphery
Channel path identifier	Host Connector	Channel path identifier	-
Logical unit number	Unit ID	Logical unit number	Host LUN or LUN

For information on device addresses in BS2000, please also refer to the “System Installation” manual [8].

When a device is generated for BS2000, the following details are required in addition to the type-specific data:

• Unit ID on SU x86 or LUN on SU /390
  Possible values:

  • Unit ID: hexadecimal, two digits in the range 00 through FF

  • LUN: 0000 through FFFF

  All values are functionally equivalent.

• Mnemonic
  Possible values:

  • alphanumeric, two characters (character set: digits and letters)

  • hexadecimal, four characters (character set: numbers from 1000 through FFFF)

  The mnemonics can be selected in such a way that every customer-specific naming schema is supported. On an MU no check is made to see whether the specification matches the mnemonic configured in BS2000. To prevent misunderstandings, they should be identical.

Every combination of the possible values is permitted.