HP XP Data Shredder Software - Manual (Page 39)

• If you use the mapped external LU from the host connected to the local array, set the IO
Suppression mode to Disable when mapping the LU. For External Storage XP, select Disable. For
Flex Copy XP, select Enable.
• If you use the mapped external LU for the copy source or copy destination volume for a Flex Copy
XP pair, set the emulation type to OPEN-V when mapping the volume.
• If you use the mapped external LU for the copy source or copy destination volume for a Flex Copy
XP pair, set IO Suppression mode to Enable when mapping the volume.
• The local array does not force the external array to reserve the mapped external LU. Therefore, do
not write directly to an external array LU (that is, without writing via the local XP array) with IO
Suppression mode set to Disable from the external array side.
If Flex Copy XP operations are in progress for a volume with IO Suppression mode set to Enable, be
careful when updating data in that external LU from the external array side.
• IO Suppression mode is automatically set to the same status for all LDEVs in a given external LU.
• Cache Mode is automatically set to the same status for all LDEVs in a given external LU.
• If you set an open-system emulation type (such as OPEN-V) when mapping the external LU, you
can use the external LU immediately.
To optionally initialize the LU's data area, use Volume Manager to format the LU. For instructions,
see the HP StorageWorks LUN Configuration and Security Manager XP user guide for the
XP12000/XP10000/SVS200.
• If you set a mainframe-system emulation type (such as 3390-3) when mapping the external LU,
format the LU or perform the Write to Control Blocks operation to make the volume usable.
After the mapping operation, the mapped LU's status is Blockade. Use Volume Manager to format the
volume or perform the Write to Control Blocks operation to make the volume usable.
• If you mapped a volume that has already been zero-formatted on the external array side,
perform the Write to Control Blocks operation.
• If you mapped a volume that has not been zero-formatted on the external array side, format
the volume on the local array side.
For instructions on the formatting and Write to Control Blocks operations, see the HP StorageWorks
LUN Configuration and Security Manager XP user guide for the XP12000/XP10000/SVS200.
If you format the external array's mapped LU from the external array side, data that existed prior to
formatting cannot be ensured. When using the mapped external LU from the mainframe OS, format
the mapped volume from the local array side.
• If you set a mainframe-system emulation type for the mapped LU, host I/O is always propagated
asynchronously to the external LU regardless of the Cache Mode setting.
• External LU attributes (IO Suppression mode and Cache Mode) set when the LU is mapped cannot
be changed while the LU is mapped. To change these attributes, delete the external LU mapping
(Delete LU operation), and remap the LU with different attributes (Add LU operation).
• External LU attributes for all LDEVs created in an external LU are set to the same values. Those
attributes are modified when the LDEVs are reconfigured using Volume Manager.
• Mapped volumes that have different external volume attributes (IO Suppression mode, Cache
Mode) cannot be used to create one LUSE volume.
• A mapped external LU with IO Suppression mode set to Enable (such as for Flex Copy XP) cannot
be used for the local array's Cache LUN XP operations.
• For a mapped external LU with IO Suppression mode set to Disable (such as for External Storage
XP), Cache LUN XP's Bind mode is not available.
• If you use the mapped external LU for Cache LUN XP operations and set the bind mode, Cache
LUN XP operations require a cache of twice the capacity of the user data.
• For External Storage XP, IO Suppression mode is typically set to Disable. You cannot use a
mapped external LU with IO Suppression mode set to Enable for pair copy operations in
Continuous Access XP, TrueCopy for z/OS®, Continuous Access XP Journal, Universal Replicator
for z/OS, Business Copy XP, ShadowImage for z/OS, or Snapshot XP. Also, the external LU
cannot be used for automatic Auto LUN XP operations.
External Storage XP user guide 39