Duplicate device numbers for different physical devices

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Figure 1 illustrates a configuration where duplicate device numbers are used to represent a console (110) and a printer (00E) within each of four logical partitions.

Figure 1. PR/SM configuration with duplicate device numbers

The following example shows the IOCP statement for Figure 1. This IOCP coding example groups the input statements by logical partition. When coding IOCP, view the I/O devices from a logical partition perspective.

CHPID PATH=(10),PARTITION=(A), . . .
CHPID PATH=(14),PARTITION=(A), . . .
CNTLUNIT CUNUMBR=0011,PATH=(10),UNITADD=(10), . . .
CNTLUNIT CUNUMBR=0012,PATH=(14),UNITADD=(0E), . . .
IODEVICE ADDRESS=(110),CUNUMBR=(0011), . . .
IODEVICE ADDRESS=(00E),CUNUMBR=(0012), . . .

CHPID PATH=(18),PARTITION=(B), . . .
CHPID PATH=(1C),PARTITION=(B), . . .
CNTLUNIT CUNUMBR=0013,PATH=(18),UNITADD=(10), . . .
CNTLUNIT CUNUMBR=0014,PATH=(1C),UNITADD=(0E), . . .
IODEVICE ADDRESS=(110),CUNUMBR=(0013), . . .
IODEVICE ADDRESS=(00E),CUNUMBR=(0014), . . .

CHPID PATH=(20),PARTITION=(C), . . .
CHPID PATH=(24),PARTITION=(C), . . .
CNTLUNIT CUNUMBR=0015,PATH=(20),UNITADD=(10), . . .
CNTLUNIT CUNUMBR=0016,PATH=(24),UNITADD=(0E), . . .
IODEVICE ADDRESS=(110),CUNUMBR=(0015), . . .
IODEVICE ADDRESS=(00E),CUNUMBR=(0016), . . .

CHPID PATH=(28),PARTITION=(D), . . .
CHPID PATH=(2C),PARTITION=(D), . . .
CNTLUNIT CUNUMBR=0017,PATH=(28),UNITADD=(10), . . .
CNTLUNIT CUNUMBR=0018,PATH=(2C),UNITADD=(0E), . . .
IODEVICE ADDRESS=(110),CUNUMBR=(0017), . . .
IODEVICE ADDRESS=(00E),CUNUMBR=(0018), . . .

Eight IODEVICE statements are used, one for each console and one for each printer that has a duplicate device number. Device numbers 110 and 00E occur four times each; however, they are not duplicated within a logical partition. When coding an IOCP input file, remember that the unique device number rule applies for logical partitions in an IOCDS.

Figure 2 shows another example of a logical partition configuration in which the device number for a console (110) is duplicated for all four logical partitions.

Figure 2. Duplicate device numbers for console

The following example shows the IOCP coding for the previous configuration. Four IODEVICE and four CNTLUNIT statements are used, one each for the console within each logical partition that has a duplicate device number.

CHPID PATH=(10),PARTITION=(A), . . .
CHPID PATH=(14),PARTITION=(A), . . .
CNTLUNIT CUNUMBR=0001,PATH=(10,14),UNITADD=((10)), . . .
IODEVICE ADDRESS=(110),CUNUMBR=(0001), . . .

CHPID PATH=(18),PARTITION=(B), . . .
CHPID PATH=(1C),PARTITION=(B), . . .
CNTLUNIT CUNUMBR=0002,PATH=(18,1C),UNITADD=((10)), . . .
IODEVICE ADDRESS=(110),CUNUMBR=(0002), . . .

CHPID PATH=(20),PARTITION=(C), . . .
CHPID PATH=(24),PARTITION=(C), . . .
CNTLUNIT CUNUMBR=0003,PATH=(20,24),UNITADD=((10)), . . .
IODEVICE ADDRESS=(110),CUNUMBR=(0003), . . .

CHPID PATH=(28),PARTITION=(D), . . .
CHPID PATH=(2C),PARTITION=(D), . . .
CNTLUNIT CUNUMBR=0004,PATH=(28,2C),UNITADD=((10)), . . .
IODEVICE ADDRESS=(110),CUNUMBR=(0004), . . .