HP StorageWorks XP Remote Web Console Software - Manual (Page 12)

12 Compatible PAV Function for the XP1024/XP128/XP12000/XP10000
Figure 1 Flow of I/O Requests Using Compatible PAV
In the above figure, the alias devices A, B and C are assigned to the base device 1, the alias devices D, E
and F are assigned to the base device 2, and the alias devices G, H and I are assigned to the base device
3 within a LCU or CU image. If you use Compatible PAV, only the alias device that is assigned in advance
to each base device works as an alias device.
For example, If I/O requests have converged on the base device 1 when a host computer accesses the
base device 1 by using Compatible PAV, I/O requests will be issued to the alias device A, B or C
automatically. If a host computer accesses similarly to the base devise 2 or 3, I/O requests will be also
issued to the alias device that are assigned in advance automatically.
The base device 4 cannot use any alias devices when I/O requests are issued by using Compatible PAV
because any alias devices are not assigned to the base device 4.
Compatible Hyper PAV Function
Compatible Hyper PAV was evolved for XP12K/10K static Compatible PAV and dynamic Compatible PAV.
If you use Compatible Hyper PAV, alias devices that were assigned to a base device are shared with all
base devices in the same LCU or CU image. Thereby, alias devices do not need to be shifted by dynamic
Compatible PAV. Moreover, you can use more devices for a base device than when you use Compatible
PAV because you can reduce devices that are assigned for an alias device as WLM is no longer used so
LPAR's can use the same aliases..
You can specify the type of PAV (Compatible PAV or Compatible Hyper PAV) to use for each host computer.
Therefore, an alias device may accept both I/O requests that are issued when you use the Compatible PAV
and Compatible Hyper PAV.
Compatible Hyper PAV is supported by version 50-09-5x or later.
Figure 2 Flow of I/O Requests Using Compatible Hyper PAV
In the above figure, the alias devices A, B and C are assigned to the base device 1, the alias devices D, E
and F are assigned to base device 2, and alias devices G, H and I are assigned to the base device 3
within a LCU or CU image. If you use Compatible Hyper PAV, all alias devices that were assigned in