HP StorageWorks XP Remote Web Console Software - Manual (Page 45)

Restrictions. If you plan to use PPRC commands instead of the TrueCopy for Mainframe software
to perform TrueCopy for Mainframe operations, the following restrictions apply:
•
System option mode 114 (see “XP Disk Array Modes for TrueCopy for Mainframe” (page 12) )
must be enabled to allow automatic port configuration in response to PPRC commands. To
fully support an automated environment, the HP disk array is capable of automatically
configuring a Fibre Channel port as an initiator or RCU target port if required in response to
the TSO CESTPATH and CDELPATH commands. However, even if you set ON for system
option mode 114, initiator ports will not automatically change to RCU target ports, nor vice
versa, when these ports are in initiator/external mix mode. The HP disk array will make sure
that the specified MCU port is offline to the host, and will automatically configure it as an
initiator port if required. Similarly, the corresponding RCU port will also be configured as an
RCU target port if required. When the CDELPATH command is issued, the TrueCopy for
Mainframe logical paths are removed, and if there are no more TrueCopy for Mainframe or
XP Continuous Access Software logical paths on the port, the port is automatically changed
from initiator port mode to RCU target port mode.
For Fibre Channel interface, do not use the CESTPATH and CDELPATH commands at the same
time as the SCSI path definition function of LUN Manager. The Fibre Channel interface ports
need to be configured as initiator ports or RCU target ports before the CESTPATH and
CDELPATH commands are issued.
CAUTION: Before issuing the CESTPATH command, you must make sure that the relevant
paths are offline from the host(s) (for example, configure the Chipid offline, or deactivate the
LPAR, or block the port in the ESCD). If any active logical paths still exist, the add path
operation will fail because the port mode (RCU Target/Initiator) cannot be changed.
•
The PPRC commands do not allow you to:
Change the RCU and CU options. The current default values are: minimum paths = 1, RIO
MIH time = 15 sec, incident of RCU = to any host, PPRC support = yes, remote copy ◦
service SIM = not report, Freeze option = disable. The TrueCopy for Mainframe software
must be used to change these options.
◦ Change the TrueCopy for Mainframe async options. The current default values are: sidefile
threshold = 50%, offloading timer = 5 minutes. The TrueCopy for Mainframe software
must be used to change these options.
◦ Configure TrueCopy for Mainframe Asynchronous consistency groups. Since each TrueCopy
for Mainframe Asynchronous pair must belong to one group, the TrueCopy for Mainframe
software must be used to add and configure the groups (timer type, copy pending timeout,
RCU ready timeout) before you can add any TrueCopy for Mainframe Asynchronous
pairs. Once the async options, groups, and group options are configured, the PPRC
commands can be used to control/monitor TrueCopy for Mainframe Asynchronous pairs.
◦ Change the initial copy priority, CFW data option, or DFW to R-VOL option. If CESTPAIR
is used to establish a TrueCopy for Mainframe pair, the following options will be used:
initial copy priority = 0, CFW data = copy to R-VOL, and DFW to R-VOL = not required.
The TrueCopy for Mainframe software must be used to change these options.
The DFW to R-VOL setting does not affect the I/O performance of the M-VOLs. If one side
of cache is closed due to an RCU failure, the TrueCopy for Mainframe copy operation
still uses DFW. The only difference between not required and required is that new pairs
cannot be established with the DFW-to-R-VOL required option when one side of RCU
cache is closed (the add pair operation fails).
When you create a TrueCopy for Mainframe pair, and if you select only M-VOL for the
CFW data option, the data set which is updated by CFW in M-VOL cannot be used in
R-VOL. To use this data set in R-VOL, release a TrueCopy for Mainframe pair, and format
the data set.
PPRC Support 45