HP XP P9000 Continuous Access Synchronous for Mainframe Systems User Guide

Continuous Access Journal Z
Cnt Ac-S Z and Continuous Access Journal Z can share the same pair volumes. Using a combined
Cnt Ac-S Z and Cnt Ac-J Z configuration can extend disaster recovery options to a third data center.
Like Cnt Ac-S Z, a Cnt Ac-J Z pair maintains a copy of the production volume in a second location.
However, unlike Cnt Ac-S Z, the Cnt Ac-J Z S-VOL is asynchronous, and the remote system can be
located much greater distances from the local and remote Cnt Ac-S Z sites.
Creating both a Cnt Ac-S Z and a Cnt Ac-J Z backup ensures that a copy in a third location is
available in the event that the primary site or one of the systems fails.
Configurations consisting of Cnt Ac-S Z and Cnt Ac-J Z pair volumes are covered extensively in
the HP XP P9000 Continuous Access Journal for Mainframe Systems User Guide.
Virtual LVI/LUN
Virtual LVI/LUN volumes can be assigned to Cnt Ac-S Z pairs, with the following restrictions:
• The S-VOL must have the same capacity as the P-VOL.
• When performing Virtual LVI/LUN operations on an existing Cnt Ac-S Z P-VOL or S-VOL, you
must release the pair first to return the volume to Simplex status.
For more information, see the HP XP P9000 Provisioning for Mainframe Systems User Guide.
Auto LUN
The following table shows when Cnt Ac-S Z volumes may be used as Auto LUN volumes.
Used as Auto LUN volume?Volume/pair status
NoP-VOL/S-VOL in Pending Duplex status
YesP-VOL/S-VOL in Duplex status
YesP-VOL/S-VOL in Suspend status
Restrictions
The following restrictions must be followed when a Cnt Ac-S Z volume in Duplex status is used as
a Auto LUN volume:
• Set I/O rates less than 50 IOPS while migrating volumes; if more than 50 IOPS, volumes may
not be migrated.
• If a data path failure occurs, remove the failure then migrate the volume.
• If an external volume or a THP V-VOL is used, information from before the volume is migrated
is displayed in the remote system Remote Web Console window. If the Auto LUN is completed
and the Cnt Ac-S Z pair is suspended and resynchronized, the volume’s information is updated.
• Do not migrate P-VOL and S-VOL at the same time, or a host I/O timeout will occur.
• Do not change the status of a volume during migration; the status may not change.
56 Sharing Continuous Access Synchronous Z volumes