For the volume formatting and Write to Control Blocks operation procedures, see the HP StorageWorks XP24000/XP20000 Virtual LVI/LUN (VLL) and Volume Shredder User Guide.
Connecting Open Systems Volumes
Open systems volumes in external storage system connect to and are recognized by the storage system as open systems volumes, without requiring reformatting. Reformatting is not required because the connection between the storage system and the external storage system is Fibre Channel. If you need to initialize the data area for the volume, format the volume using the VLL function. For the volume formatting operation procedure, see the HP StorageWorks XP24000/XP20000 Virtual LVI/LUN (VLL) and Volume Shredder User Guide.
Choosing Mapping Policy
Mapping policy is a list of settings of the necessary information for mapping the external volume. By setting the mapping policy in advance, the setting at the time of mapping will be easier.
The default mapping policy is prepared in advance. You can change the values of the default mapping policy.
Difference between Automatic Mapping and Manual Mapping
When you map the external volume, you need to configure:
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•External volume parameters
•LDEV number to LDEVs in the external volume
•SSID (storage system ID)
When you perform automatic mapping, users configure only
Automatic mapping maps all the external volumes found by volume discovery to internal volumes. Automatic mapping requires fewer settings but you are not allowed to set different parameters for each external volume or to specify an LDEV number for each LDEV. You can set the parameters such as emulation type to the mapping policy in advance.
NOTE: In automatic mapping, external volumes are mapped in the order of the local storage system recognizing. Therefore, the LDEV number is also specified in this order. Moreover, when you copy external volumes with the program product for copying, the copy operation is performed in the order of the LDEV number if you specify two or more external volumes for the initial copy or resynchronization. Therefore, when you copy external volumes that are mapped automatically with the program product for copying, the copy operation might focus on a specific RAID group and cause insufficient performance. To prevent the copy operation from focusing on a specific RAID group, HP recommends that the external volumes be mapped manually so that the copy operation is distributed to two or more RAID groups.
Port Discovery and Volume Discovery
Port discovery and volume discovery are methods used to find external volumes, and are executed when you map external volumes or when you add
•Port discovery searches for and gets information about target ports of the connected external storage system from an external port of the local storage system. The latest information about