Table 1 1 Option modes for Continuous Access Synchronous Z (continued)
Planning for system performance
Remote copy operations can affect I/O performance on the host as well as the main and remote
disk arrays. Continuous Access Synchronous Z provides several options for minimizing the impact
Allows you to change the volume that is suspended when the FREEZE command is issued from the
host. The target will change from the volume in the CU for which the FREEZE command is issued to
the volume in the entire DKC if this mode is ON.
Mode 64 ON: The volume in the entire DKC is suspended.
Mode 64 OFF: The volume in the CU for which the FREEZE command is issued is suspended.
Allows dynamic port mode setting (Initiator/RCU target for Fibre Channel) through PPRC CESTPATH
and CDELPATH commands.
Mode 1 14 ON: Initiator ports automatically change to RCU target ports. or vice versa.
Mode 1 14 OFF (default): Initiator ports do not change to RCU target ports, or vice versa.
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. Fibre Channel interface ports need to be
configured as initiator ports or RCU target ports before the CESTPATH and CDELPATH commands
Even if you set system option mode 1 14 ON, initiator ports will not automatically change to RCU
target ports, nor vice versa, when these ports are in initiator/external mix mode.
Allows you to update the VOLSER and VTOC of the R-VOL while the pair is suspended, if both mode
20 and 190 are ON.
Allows you to select whether the Remote Copy Path status, SIM218x, is reported to the host or not.
Mode 308 ON: SIM218x will be reported to the host.
Mode 308 OFF: SIM218x will not be reported to the host.
Allows you to select the indication type if you use the PPRC CQUERY command to display the remote
copy path status.
Mode 484 ON: The status of path using the Fibre Channel interface is displayed. WWNN will
Mode 484 OFF: The status of path using an ESCON interface is displayed. WWNN is invalid.
If the a previous model storage system or the storage system of XP12000 Disk Array/XP10000 Disk
Array microcode version 50-05-XX-XX or earlier is connected, mode 484 must be OFF.
Allows you to specify when the Basic HyperSwap function of TPC-R is used. This function can allow
the CESTPATH operation to establish a path to several RCUs at a time. Since attributes of a port are
switched if the CESTPATH operation is performed with system option mode 144 ON, the path status
between the main storage system and remote storage system is changed to linkdown. If the CESTPATH
operation is performed to two or more RCUs, MIH may be reported to a host, and the other CESTPATH
operation, which has detected the linkdown path, retries the CESTPATH operation. To disable an
MIH report to a host, set the system option mode to ON to disable the CESTPATH and retry the
operation when a linkdown is detected.
Mode 769 ON: Does not retry when linkdown is detected during the CESTPATH operation.
Mode 769 OFF: Retries when linkdown is detected during the CESTPATH operation.
Allows you to select whether to output the F/M = FB message to the host of MCU when the suspension
or the release operation is performed from Business Continuity Manager to the R-VOL of Continuous
Access Synchronous Z pair in the Duplex status.
Mode 776 ON: The F/M = FB message is not output.
Mode 776 OFF: The F/M = FB message is output.
This mode must be set to both MCU and RCU.
Planning for system performance