MAS Technical Note - Defining the MAS to MVS

Defining the MAS™ to MVS, OS/390, z/OS

The MAS connects to FICON or ESCON channel(s) of an IBM (or compatible) mainframe. Before you can use the MAS you must configure the operating system to recognize the newly attached MAS virtual tape devices.

Overview

Many MVS installations use generic device types such as 3480, 3490, TAPE, or CART in their JCL to assign drives for their tape jobs. When this is the case, unique device types must be configured for the MAS virtual tape drives to control which jobs will go to the MAS. Otherwise, jobs that are supposed to go to physical tape drives could inadvertently be assigned to MAS virtual tape drives, or vice versa.

Bus-Tech provides a UIM (Unit Information Module) and UDT (Unit Data Table) that must be installed and copied into SYS1.NUCLEUS. Installation of this UIM and UDT is described in the MAS Installation and User’s Guide.

Once the UIM is installed, there will be four new control unit types available for definition of MAS devices: V3480, V3481, V3482 and V3483. We have provided multiple virtual device types in order to provide support for either multiple MAS systems or a single MAS with multiple tape libraries. This way, the user can target a specific MAS or a specific tape library by coding the designated device type in the JCL.

NOTE: Bus-Tech's UIM does not allow AUTOSWITCH to be configured.

As an alternative to using the UIM, MAS devices can also be defined as UNIT=3490. When defining the MAS devices as 3490 tape drives, an MTL should also be defined to differentiate the MAS devices if other 3490 tape drives are present on the Host. Further information regarding this is available in the MAS Installation and User’s Guide, available as a PDF file on the MAS main support page.

The MAS supports up to 256 device addresses (depending on model), though your application may use fewer. To allow for maximum growth without having to redo the I/O configuration, we suggest you configure the maximum number of addresses on the mainframe at the time of the initial installation even if you don't plan to use them all at first. Please refer to your copy of the MAS Installation and User’s Guide for detailed information regarding the maximum number of devices your particular MAS can support.

FICON Configuration Information

ESCON Configuration Information

Connecting the MAS to a FICON Channel

The MAS can be connected directly to the mainframe FICON channel or it can be connected through a FICON switch. I/O generation examples for both kinds of connections are shown below.

In either case, to properly define a MAS V348x, or 3490, or 3480 device on an MVS system, the following parameters are required:

TYPE must be FC.

UNIT can be one of the virtual device types: V3480, V3481, V3482 or V3483
OR
UNIT could also be defined as a real 3490
OR
UNIT could also be defined as a real 3480.

The CHPID can be defined as any one of the following - SHARED, DED or REC.

When configuring MAS devices as device type 3490 the maximum number of devices per control unit is 16.

Configuration for a direct FICON connection

Basic, Dedicated Non-Shared (Non-EMIF) Mode


    CHPID PATH=(0A),DED,TYPE=FC

    CNTLUNIT CUNUMBR=EA80,PATH=(0A),                     +
             UNITADD=((00,32)),UNIT=V3480

    IODEVICE ADDRESS=(EA80,32),CUNUMBR=(EA80),           +
             STADET=Y,UNIT=V3480

Note: With dedicated non-EMIF (non-shared) mode, in the MAS virtual device configuration program specify LPAR=0 regardless of the LPAR to which it will be connected. See the MAS Installation and User’s Guide for more information.

Reconfigurable Non-Shared (Non-EMIF) Mode


    CHPID PATH=(0A),REC,TYPE=FC

    CNTLUNIT CUNUMBR=EA80,PATH=(0A),                     +
             UNITADD=((00,32)),UNIT=V3480

    IODEVICE ADDRESS=(EA80,32),CUNUMBR=(EA80),           +
             STADET=Y,UNIT=V3480

Note: With reconfigurable non-EMIF (non-shared) mode, in the MAS virtual device configuration program specify LPAR=0 regardless of the LPAR to which it will be connected. See the MAS Installation and User’s Guide for more information.

Shared (EMIF) Mode


    CHPID PATH=(0A),SHARED,TYPE=FC

    CNTLUNIT CUNUMBR=EA80,PATH=(0A),                     +
             UNITADD=((00,32)),UNIT=V3480

    IODEVICE ADDRESS=(EA80,32),CUNUMBR=(EA80),           +
             STADET=Y,UNIT=V3480

Note: With EMIF (shared) mode, in the MAS virtual device(s) configuration program specify LPAR=n where n is the LPAR to which the MAS device is connected. See the MAS Installation and User’s Guide for more information.

Alternate Paths in Shared (EMIF) Mode


    CHPID PATH=(0A),SHARED,TYPE=FC
    CHPID PATH=(0B),SHARED,TYPE=FC

    CNTLUNIT CUNUMBR=EA80,PATH=(0A,0B),                  +
             UNITADD=((00,32)),UNIT=V3480

    IODEVICE ADDRESS=(EA80,32),CUNUMBR=(EA80),           +
             STADET=Y,UNIT=V3480

Configuration for a FICON Switch in Basic Mode


    CHPID PATH=((22)),TYPE=FC,SWITCH=02

    CNTLUNIT CUNUMBR=300,PATH=(22),LINK=(C2),            +
             UNITADD=((00,32)),UNIT=V3480

    IODEVICE ADDRESS=(300,32),CUNUMBR=(300),UNIT=V3480

Connecting the MAS to an ESCON Channel

The MAS can be connected directly to the mainframe ESCON channel or it can be connected through an ESCON director. I/O generation examples for both kinds of connections are shown below.

In either case, to properly define a MAS V348x, or 3490, or 3480 device on an MVS system, the following parameters are required:

TYPE must be CNC.

UNIT can be one of the virtual control units: V3480, V3481, V3482 or V3483
OR
UNIT could also be defined as a real 3490
OR
UNIT could also be defined as a real 3480.

The CHPID can be defined as any one of the following - SHARED, DED or REC.

When configuring MAS devices as device type 3490 the maximum number of devices per control unit is 16.

Configuration for a direct ESCON connection

Basic, Dedicated Non-Shared (Non-EMIF) Mode


    CHPID PATH=(0A),DED,TYPE=CNC

    CNTLUNIT CUNUMBR=EA80,PATH=(0A),                     +
             UNITADD=((00,32)),UNIT=V3480

    IODEVICE ADDRESS=(EA80,32),CUNUMBR=(EA80),           +
             STADET=Y,UNIT=V3480


    CHPID PATH=(0A),REC,TYPE=CNC

    CNTLUNIT CUNUMBR=EA80,PATH=(0A),                     +
             UNITADD=((00,32)),UNIT=V3480

    IODEVICE ADDRESS=(EA80,32),CUNUMBR=(EA80),           +
             STADET=Y,UNIT=V3480


    CHPID PATH=(0A),SHARED,TYPE=CNC

    CNTLUNIT CUNUMBR=EA80,PATH=(0A),                     +
             UNITADD=((00,32)),UNIT=V3480

    IODEVICE ADDRESS=(EA80,32),CUNUMBR=(EA80),           +
             STADET=Y,UNIT=V3480


    CHPID PATH=(0A),SHARED,TYPE=CNC
    CHPID PATH=(0B),SHARED,TYPE=CNC

    CNTLUNIT CUNUMBR=EA80,PATH=(0A,0B),                  +
             UNITADD=((00,32)),UNIT=V3480

    IODEVICE ADDRESS=(EA80,32),CUNUMBR=(EA80),           +
             STADET=Y,UNIT=V3480

Configuration for an ESCON Director in Basic Mode


    CHPID PATH=((22)),TYPE=CNC,SWITCH=02

    CNTLUNIT CUNUMBR=300,PATH=(22),LINK=(C2),            +
             UNITADD=((00,32)),UNIT=V3480

    IODEVICE ADDRESS=(300,32),CUNUMBR=(300),UNIT=V3480