HP XP External Storage Software - Manual (Page 25)

Figure 11 Single Mode with Alternate Paths in Standby Only
Connecting Mainframe Volumes
Mainframe volumes that pre-exist on an external storage system and are accessed by ESCON or
FICON channels cannot connect directly to the storage system as an external volume. The storage
system does not recognize these volumes because of Fibre Channel.
To use external volumes as mainframe volumes, there are two ways:
•
Zero-format external volumes on the external storage system side, map the external volumes
to the internal volumes using XP External Storage on the local storage system side, and then
perform the Write to Control Blocks operation using the VLL function on the local storage system
side.
•
Map the external volumes to the internal volumes using XP External Storage on the local storage
system side, and then format the mapped external volumes using the VLL function on the local
storage system side.
If you set the emulation type for the mainframe system (such as 3390) as you map the external
volume, the status of the mapped volume becomes Blockade after the mapping operation. After
the system administrator performs the Write to Control Blocks operation or formats the mapped
external volumes using the VLL function on the local storage system side, the mainframe host can
then access the new mainframe volume through the local storage system's ESCON or FICON
channels.
If you format the mapped volume of the external storage system from the external storage system
side, the existing data before formatting cannot be assured. When you use the mapped external
volume from the mainframe operating system, format the mapped volume from the local storage
system side.
Configuring XP External Storage 25