Compaq StorageWorks HSZ80 Configuration And Cli Reference Manual page 129

When your controller receives an I/O request, it identifies the storageset unit number
for the request, then correlates the unit number to the storageset name. From the
storageset name, the controller locates the appropriate device for the I/O request. (For
example, the RAIDset "RAID1" might contain DISK10000, DISK20000, and
DISK30000.) The controller generates the read or write request to the appropriate
device using the PTL addressing convention. Figure 3–13 illustrates the concept of
PTL addressing.
D100
RAID1
Disk 10000 Disk 20000
Figure 3–13. Locating Devices using PTLs
Compaq HSZ80 Array Controller ACS Version 8.3 Configuration and CLI Reference Guide
Host addressable
unit number
Storageset
name
Controller
PTL addresses
Disk 30000
CXO6186A
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