Guidelines for defining the logical control unit for the DS6000

You can use these guidelines to define the logical control unit for the DS6000™.

You need the following information in order to define the logical control unit (LCU):

Which devices (arrays) are 3380 format, and which are 3390 format
Which devices have PAVs, and which do not
How many devices you define to a given LCU
Notes:
1. An LCU is equivalent to a logical subsystem (LSS). Like an LSS, an LCU can have a maximum of 256 logical devices or volumes.
2. Every device has a single unit address (in range 00 - FF).
3. An LCU can manage a maximum of 256 devices and identifies a device based on the unit address.

Update the I/O configuration with the appropriate devices, using the following guidelines:

Three device types are possible for 3380: 3380, 3380B, and 3380A.
Three device types are possible for 3390: 3390, 3390B, and 3390A.
Any non-PAV 3380 is a 3380, regardless of model.
Any non-PAV 3390 is a 3390, regardless of model.
Any 3380 PAV base is a 3380B.
Any 3390 PAV base is a 3390B.
Any alias of a 3380B, regardless of model, is a 3380A.
Any alias of a 3390B, regardless of model, is a 3390A.
Only define the actual base and alias devices to IOCP or HCD to avoid unnecessary definition of processor subchannels.
Only define the unit address range to IOCP or HCD as necessary for the installed devices in an LCU (64, 128, or 256). Defining the unit address range enables you to put more LCUs and devices on a channel path.

IBM recommends that you document the configuration you define for the DS6000. With the exception of the 3380 and 3390 models, the DS6000 configuration and the IOCP input must match.

Note: The CU device is a 1750 for any DS6000 device type. In HCD you can use 3990 as a control-unit type for 3380 and 3390 devices. However, you must use 1750 as the control-unit type for 3380B, 3380A, 3390B, and 3390A devices.