IBM Z9, Planning Manual

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In Figure 2-6, a 3174 in SNA mode is defined as five control unit headers (CUHs).
Because each 3174 CUH supports a maximum of one logical path, it is equally
important in this example that the shared channel only attempts to establish a
single logical path to each 3174 CUH.
Even though 5 LPs share the ESCON channel, the channel will only attempt 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.
Partial IOCP Deck for the Configuration: The following is a partial IOCP deck for
the example in Figure 2-6.
LP1 LP2 LP3 LP4 LP5
CHP
30
LPAR
3174 in SNA mode
LC1 LC2 LC3 LC4 LC5
LP3
LP4
LP5
LP2
LP1
Figure 2-6. Defining Devices to a Subset of Logical Partitions
2-18
PR/SM Planning Guide