HP XP P9000 Continuous Access Synchronous for Mainframe Systems User Guide

the initial copy pace, the number of maximum initial copy VOLs, and the bandwidth of the
channel extender communication lines between main and remote system.
Initial copy response time (ms) = (1[MB] / “Data path speed between MCU-RCU[MB/ms]
1
”) x (“initial copy
pace(
2
/ 15) x (number of maximum initial copy VOLs
3
” / “Number of data paths between MCU-RCU”
4
)
1. When you connect MCU with RCU without channel extenders, specify 0.17[MB/ms] in “Speed of line between
MCU and RCU”.
2. For “initial copy pace” in the preceding formula, see the following table.
3. For “number of maximum initial copy volumes”, use the value set up per storage system. The default is 64.
4. Even if the “number of maximum copy VOLs” / “Number of data paths between MCU-RCU” is larger than
16, specify “number of maximum initial copy VOLs” / “Number of data paths between MCU-RCU” as 16.
The following table shows the initial copy pace used for the response time calculation.
Initial, update copy in progressInitial copy only in progressInterface
When initial copy pace specified
at the time of pair creation is 9 to
15
When initial copy pace specified
at the time of pair creation is 1 to
8
8User-specified value between 1
and 8
User-specified valueBusiness
Continuity
Manager
8User-specified value between 1
and 8
User-specified valueRemote Web
Console
8(*)15(*)PPRC command
(TSO/ICKDSF)
and CU
emulation is
2105 or 2107
(*) When a PPRC command (TSO/ICKDSF) is used and the CU emulation type is 2105 or 2107, the initial copy pace
specified is invalid. Therefore, the fixed value will be set.
The following table shows example settings.
Round trip
time
specified
[ms]
Number of maximum
initial copy VOLs
Initial copy paceNumber of data
paths between
MCU/RCU
Data path speed
between
MCU/RCU
(MB/ms)
Round trip time
between MCU RCU
[ms]
160641540.10
220641540.130
360641540.1100
Planning pairs and pair volumes
This section discusses requirements, options, and settings you need for setting up pairs and pair
volumes. You begin by:
• Identifying data and volumes at the local site that you want to protect with a backup
• Setting up volumes at the remote site that will hold copied data.
The following helps ensure that the pairs you create fit your requirements.
• “Pair volume requirements and recommendations” (page 34)
• “Precautions for duplicate VOLSERs” (page 35)
Planning pairs and pair volumes 33