HP XP P9500 Storage - Manual (Page 144)

are assigned cannot be released. Therefore, when the pair is created using THP V-VOLs only,
page capacity or P-VOL and S-VOL license capacity might be different in the following cases:
◦ If the page in track is allocated to the P-VOL, Cnt Ac-J Z overwrites the data by copying
it to the S-VOL, even if the track has no records. The new page to which the control
cylinders are assigned might be allocated because control cylinder information controlling
the track is updated when the S-VOL data is overwritten.
In this case, pages to which the control cylinders are assigned cannot be released.
Therefore, there might be more pages allocated to the S-VOL than to the P-VOL.
◦ When P-VOL zero data pages are copied to the S-VOL, new pages might not be allocated
to S-VOL.
◦ When S-VOL data is updated while the pair is suspended, new pages to which the control
cylinders are assigned might be allocated. In this case, pages to which the control cylinders
are assigned cannot be released even after the pair is resumed. Therefore, there might
be more pages allocated to the S-VOL than to the P-VOL.
Virtual LVI
•
Continuous Access Journal Z supports the Virtual LVI feature, which allows you to configure
custom-size LDEVs that are smaller than standard-size LDEVs. When custom-size LDEVs are
assigned to a Continuous Access Journal Z pair, the S-VOL must have the same capacity as
the P-VOL.
•
To perform Virtual LVI operations on a pair’s P-VOL and S-VOL, the pair must be deleted and
the volumes’ status returned to Simplex.
Auto LUN
You can specify the Continuous Access Journal Z P-VOL or S-VOL as Auto LUN source volumes.
However, when Cnt Ac-J Z pair status is Pending or Duplex, do not perform the volume migration
operation; otherwise, the operation is stopped.
Cnt Ac-J Z pair volumes and journal volumes cannot be used as Auto LUN target volumes.
144 Sharing volumes