HP StorageWorks User Manual page 34

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 disk 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, the external
LU can be used 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.
• 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 disk array side,
perform the Write to Control Blocks operation.
• If you mapped a volume that has not been zero-formatted on the external disk array side, format the
volume on the local disk 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.
If you format the external disk array's mapped LU from the external disk 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 disk 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 (emulation type, 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 LUs that have different external LU attributes or reside on different arrays 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 XP12000/XP10000 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.
• Attributes originally set for an LU on an XP external disk array (such as port security, LUN security, and
Volume Retention Manager attributes) are not recognized by the local disk array when the external LU
is mapped as a local disk array internal XP LDEV. To keep the original attributes, set those attributes on
the mapped external LU from the local disk array side.
• If you mapped the external LU and previously set the VMA of LUN Security XP Extension in that volume,
the former VMA setting is superseded when you map the volume again. However, if LUN Security XP
Extension is not installed when you remap the volume, the volume with the VMA setting cannot be
mapped. To change the VMA setting, change it from the local disk array side.
• Do not combine LDEVs from multiple external LUs to create an XP12000/XP10000 LUSE volume.
• Do not update a volume being used or operated by Flex Copy XP. Also do not update the external LU
on the external disk array side.
34 External Storage XP for the XP12000/XP10000