HP XP P9500 Storage - Manual (Page 22)

Please see “Planning ports for data transfer ” (page 39) for a full discussion on the type and number
of fibre-channel ports required for your system.
Planning journal volumes
In addition to sizing journal volumes, you should be aware of the following requirements and
restrictions.
•
Journal volumes must be registered in a journal before the initial pair-copy operation is
performed.
•
Journal volumes must be registered on both the local and remote systems.
•
Emulation type for journal volumes must be OPEN-V.
•
Journal volumes should be sized according to RPO and write-workload. See “Sizing journal
volumes ” (page 20) for more information.
•
If a path is defined from a host to a volume, the volume cannot be registered as a journal
volume.
•
Journal volumes in a journal can have different capacities.
•
A master journal volume and the corresponding restore journal volume can have different
capacities.
•
A data volume and its associated journal volume can belong to only one journal.
•
Do not register a volume to a journal during quick formatting. Doing so stalls the operation.
•
Data volumes and journal volumes in the same journal must belong to the same controller.
•
The number of journal volumes in the master journal does not have to be equal to the number
of volumes in the restore journal.
•
Journal volumes consist of two areas: One area is used for storing journal data, and the other
area is used for storing metadata for remote copy.
•
Journal volumes support all RAID configurations and physical volumes that are supported by
P9500.
•
Journal volume capacity is not included in accounting capacity.
•
Customized volumes can be used for journal volumes.
See the following for more information about journals and journal volumes:
•
The “Journals” item in “System requirements” (page 15)
•
“Planning journals ” (page 20)
Planning pair volumes
The following information can help you prepare volumes for configuration. Also, see system
requirements and specifications in
“Requirements and specifications” (page 15) for more information.
•
The emulation and capacity for the S-VOL must be the same as for the P-VOL
•
When the S-VOL is connected to the same host as the P-VOL, the S-VOL must be defined to
remain offline.
•
You can create a Cnt Ac-J pair using a Continuous Access Synchronous initial copy, which
takes less time. To do this, system option 474 must be set on the primary and secondary
systems. Also, a script is required to perform this operation. For more on system option 474
and how to do this operation, see
“System option modes ” (page 31) .
•
Cnt Ac-J supports the LUN Expansion feature, which allows you to configure a LUSE volume
by using 2 to 36 sequential LDEVs. If two LUSE volumes are assigned to a Cnt Ac-J pair, the
capacity and configuration of the Cnt Ac-J S-VOL must be the same as the Cnt Ac-J P-VOL. For
22 Planning volumes, P9500 systems