Partial IOCP Deck for the Configuration

Following is a partial IOCP deck for the example in Figure 1.

CHPID PATH=30,SHARED

CNTLUNIT CUNUMBR=10,PATH=30
IODEVICE ADDRESS=VVVV,CUNUMBR=10,PART=LP1

CNTLUNIT CUNUMBR=11,PATH=30
IODEVICE ADDRESS=VVVV,CUNUMBR=11,PART=LP2

CNTLUNIT CUNUMBR=12,PATH=30
IODEVICE ADDRESS=VVVV,CUNUMBR=12,PART=LP3

CNTLUNIT CUNUMBR=13,PATH=30
IODEVICE ADDRESS=VVVV,CUNUMBR=13,PART=LP4

CNTLUNIT CUNUMBR=14,PATH=30
IODEVICE ADDRESS=VVVV,CUNUMBR=14,PART=LP5

Figure 1. Defining devices to a subset of logical partitions

In Figure 2, a DS8K is configured as 5 logical control units or control nit images and is defined as five control unit headers (CUHs). Each control unit image has a logical path limit which may need to be managed.

Even though 5 LPs share the FICON channel, the channel only attempts to establish a logical path for LP1 to CUH 0 because only LP1 has a device defined on that CUH. Similarly, only LP2 can access CUH 1, only LP3 can access CUH 2, only LP4 can access CUH 3, and only LP5 can access CUH 4.