HP XP P9500 Storage - Manual (Page 147)

Restrictions for Auto LUN
Auto LUN must be used within the following restrictions:
•
Business Copy (HOMRCF). The operation for the volume migration must be operated at the
“SMPL” or “PAIR” or “COPY” state. If not, paircreate -m cc command is rejected with
EX_CMDRJE or EX_CMDIOE. Also Business Copy cannot be operated to CC_S-VOL moving
in Auto LUN. In copying CC_S-VOL, the copy operation for the volume migration is stopped,
if the Business Copy pairsplit command is executed.
•
Continuous Access Synchronous (HORC). The operation for the volume migration must be
performed at the “SMPL” or “PSUS” state. If not, paircreate -m cc command is rejected
with EX_CMDRJE or EX_CMDIOE. Also HORC cannot be operated to CC_S-VOL copying in
Auto LUN. On one hand, in copying CC_S-VOL, the copy operation for the volume migration
is stopped, if pairresync command for of HORC is executed.
•
LDEV type for Auto LUN. The volume of the external connection for the volume migration must
be mapped to an LDEV as OPEN-V.
For details on Auto LUN, see the HP P9000 Auto LUN User Guide.
Continuous Access Journal MxN configuration and control
Overview
Continuous Access Journal supports 4X4 by using sysplex timers on the mainframe. However, open
systems do not have an equivalent of sysplex timers on the mainframe, because the SCSI protocol
does not have timestamps.
If the open system (RAID Manager) has the timestamp as an equivalent of sysplex timers, Continuous
Access Journal supports 4X4 on the open system.
•
RAID Manager: delivers the timestamp(CTQ-Marker) to the consistency group
•
Storage system (RCU): arbitrates the timestamp(CTQ-Marker) across multiple storage system
connected remote command devices, and then commits the journal data.
In this architecture, RAID Manager needs to be running. If RAID Manager has stopped, the DKC
(RCU) function does not appear to exist. Therefore, the better architecture is to include the DKC(RCU)
function into RAID Manager.
RAID Manager already supports the group control across multiple DKC in the Cnt Ac-S_Sync group.
This means that RAID Manager can support Continuous Access Journal MxN on the open system
if RAID Manager is capable of delivering the timestamps and committing the Journal data with a
CTQ-Marker.
Continuous Access Journal MxN configuration and control 147