HP XP7 Continuous Access Synchronous for Mainframe Systems User Guide (TK911-96003)

RCU registration (CESTPATH)
• RCU options. If CESTPATH is used to create a path, the following default values are used:
Minimum Paths = 1◦
◦ RIO MIH Time = 15 sec
◦ Round Trip Time = 1 ms
The CGROUP option of the CESTPATH command applies to the FREEZE option.
• CU options. If CESTPATH is used to create a path, the following default values are used:
PPRC support by host = Yes◦
◦ Services SIM of Remote Copy = Not Report
Pair creation (CESTPAIR)
The options for pair creation are Initial Copy Priority, CFW Data (cache fast write), and DFW to
Secondary Volume (DASD fast write). If CESTPAIR is used to create a pair, the following values
are used for these options:
• Initial copy priority = 0
• CFW Data = Secondary Volume Copy. If you select the only P-VOL value, the data set that is
updated by CFW in the P-VOL cannot be used in the S-VOL. To use this data set in the S-VOL,
release the pair and format the data set.
• CFW Data = Primary Volume Only. You can set this using PPRC when the Remote Copy
Function Switch is used. Contact your HP account team for more information.
• DFW to S-VOL = DFW not required. This setting does not affect P-VOL I/O performance. If
one side of cache is closed due to a secondary system failure, the copy operation still uses
DFW. The difference between not required and required is that new pairs cannot be established
with the required option when one side of RCU cache is closed. In this case, the Add Pair
operation fails (This restriction applies only when the CU emulation type of RCU is 3390).
PPRC, BCM command comparison
BCM and PPRC are independent functions. Do not use BCM and PPRC for the same pair operation.
The following table lists the PPRC commands and corresponding BCM commands.
Support typeBCM commandParameterPPRC command
configYKBLDPTHDEVNCESTPATH
configPRIM
configSEC
configLINK
Not supportedCGROUP
Not supportedRESETHP
configYKMAKE or YKRESYNCDEVNCESTPAIR
configPRIM
configSEC
Command (RESYNC)MODE
Parameter (NOCOPY)
18 Requirements and specifications