HP XP External Storage Software - Manual (Page 34)

Powering local arrays on or off
To power local arrays off
CAUTION:
When you want to turn off both the local array and the external array, you first need turn off the local
array, and then turn off the external array.
1. Stop read and write I/Os to the external LU that is mapped as a local array internal LDEV.
2. Perform other operations required before powering the local array off.
3. Turn the local array's power off.
NOTE:
As you turn the local array's power off, all data for the external LU in the local array's cache memory is
written in the external LU (all data is destaged).
To power local arrays on
CAUTION:
When you want to turn on both the local array and the external array, you first need to turn on the external
array, and then turn on the local array.
1. Power on the external array containing the external LU mapped as a local array internal LDEV.
2. Turn on the local array's power.
CAUTION:
When the local array is powered off after executing the Disconnect Subsystem command, you cannot
access the mapped external LU from the local array when you first power on the local array. You must
execute the
Check Paths & Restore Vol . command to resume using the mapped external LU. The
Check Paths & Restore Vol. command checks if the defined information and actual status of the external
LU mapped as a local array volume match. If the external LU is ready to be used as a mapped volume,
the LU is set to accept I/Os and you can resume using the volume as a mapped volume.
CAUTION:
When the Disconnect Subsystem or Disconnect Volume command is executed and all data in cache memory
is written to the external LU, the displayed information for Ex-Dev. Status in the Device list becomes
Disconnect.
Preparing for External Storage XP operations 34