HP StorageWorks XP12000 User manual

HP StorageWorks
Continuous Access XP user guide
for the XP12000/XP10000
Part number: T1711-96005
Third edition: March 2006

Legal and notice information
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Continuous Access XP user guide for the XP12000/XP10000

Continuous Access XP user guide for the XP12000/XP10000 3
About this guide. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Intended audience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Prerequisites. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Firmware versions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Related documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Document conventions and symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
HP technical support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Subscription service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Helpful web sites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
1 Continuous Access XP for the XP12000/XP10000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Overview of Continuous Access XP operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
XP12000/XP10000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Main and remote control units (MCUs and RCUs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Volume pairs (P-VOLs and S-VOLs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Continuous Access XP Asynchronous consistency groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Remote copy connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Initiator ports and RCU target ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Remote control ports (RCPs) and local control ports (LCPs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Command View XP management station or XP Remote Web Console . . . . . . . . . . . . . . . . . . . . . . 18
Host failover software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Remote copy operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Initial copy operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Update copy operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Read and write I/O operations for Continuous Access XP volumes . . . . . . . . . . . . . . . . . . . . . . . . 20
S-VOL write option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Continuous Access XP Asynchronous recordset operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Creating and storing recordsets at the MCU. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Sending recordsets to the RCU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Storing recordsets at the RCU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Selecting and settling recordsets at the RCU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Types of recordsets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Inflow control of recordsets. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Inflow control by MCU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Inflow control by RCU. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Continuous Access XP Asynchronous consistency group operations . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Group options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Copy pending timeout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
RCU ready timeout. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Group operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Continuous Access XP volume pair status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Continuous Access XP LUSE pair status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Continuous Access XP Asynchronous pair status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Continuous Access XP split types (PSUS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Continuous Access XP suspend types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Continuous Access XP Asynchronous suspension conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Preparing for Continuous Access XP operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
System requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Requirements and restrictions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
One-to-one volume copy operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Logical unit (LU) types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Consistency groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Accessing Continuous Access XP P-VOLs and S-VOLs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Contents

4
Cache and nonvolatile storage (NVS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Host failover software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Duplicate volumes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Host system crash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Installing hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Fibre Channel remote copy connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Configuring MCUs and RCUs for Continuous Access XP operations . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Fibre Channel configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Combining Continuous Access XP with other data management operations . . . . . . . . . . . . . . . . . . . . 37
Combining Continuous Access XP and BC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Combining Continuous Access XP and LUN Security XP Extension. . . . . . . . . . . . . . . . . . . . . . . . . 43
Copying access attributes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
License capacity for LUN Security XP Extension. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Combining Continuous Access XP and Volume Manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Combining Continuous Access XP and Custom Volume Size (CVS) . . . . . . . . . . . . . . . . . . . . . . . . 46
Combining Continuous Access XP and Cache LUN XP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Combining Continuous Access XP and LUN Manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Combining Continuous Access XP and Auto LUN XP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Combining Continuous Access XP and Performance Control XP . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Starting Continuous Access XP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Continuous Access XP panes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Continuous Access XP main pane (Pair Operation pane) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Volume list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Display Filter pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Continuous Access XP Snapshot function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Creating and exporting (downloading) Continuous Access XP snapshot files . . . . . . . . . . . . . . . . . 54
RCU Operation pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
CU Number tree and MCU/RCU list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Port tree and Port list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Asynchronous Operation pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Usage Monitor pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
History Operations pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Other Operation pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Changing subsystem settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Viewing subsystem settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Changing subsystem settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Performing Continuous Access XP configuration operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
MCU operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Configuring MCU ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
RCU operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Viewing RCU Status (RCU Status) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Registering RCUs (Add RCU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Registering RCUs to the connected MCU. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Modifying RCU options (Change RCU Option) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Deleting RCUs (Delete RCU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
RCU path parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Adding and deleting logical paths for RCUs (Add Path/Delete Path) . . . . . . . . . . . . . . . . . . . . . . . 73
Adding new logical paths from the connected MCU to an existing RCU:. . . . . . . . . . . . . . . . . . 74
Deleting paths from the connected MCU to an existing RCU:. . . . . . . . . . . . . . . . . . . . . . . . . . 74
Adding and deleting SSIDs for RCUs (Add SSID/Delete SSID) . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Port change operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Modifying parameters and deleting settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Modifying parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Deleting RCUs, paths, or SSIDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Continuous Access XP Asynchronous operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Viewing consistency group status (CT Group Status) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Adding consistency groups (Add CT Group) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Modifying consistency group options (CT Group Option). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Deleting consistency groups (Delete CT Group). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

Continuous Access XP user guide for the XP12000/XP10000 5
Asynchronous copy option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Modifying parameters and deleting consistency groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Modifying parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Deleting consistency groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Usage Monitor operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Starting and stopping monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Starting remote copy usage monitoring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Stopping remote copy usage monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Displaying usage monitor graph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Optimizing Continuous Access XP operations and disk array performance . . . . . . . . . . . . . . . . . . . . . 87
Discontinuing Continuous Access XP operations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Performing Continuous Access XP pair operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Common procedure for Continuous Access XP pair operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
List after command selection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Modifying parameters and deleting LUs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Modifying LU parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Deleting LUs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Viewing Continuous Access XP pair status for LUs and LDEVs (Pairdisplay) . . . . . . . . . . . . . . . . . . . . . 91
Creating Continuous Access XP volume pairs (Paircreate) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Continuous Access XP initial copy and pair options of the Paircreate pane. . . . . . . . . . . . . . . . . . . 95
Fence Level (Continuous Access XP Synchronous only) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Initial Copy parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Asynchronous parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Splitting Continuous Access XP pairs (Pairsplit-r). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Resuming Continuous Access XP volume pairs (Pairresync) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Deleting Continuous Access XP volume pairs (Pairsplit-S). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Changing pair options (Change Pair Option) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
Using Continuous Access XP for data migration and duplication . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Data migration using Continuous Access XP Synchronous . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Point-in-Time data duplication using Continuous Access XP Asynchronous . . . . . . . . . . . . . . . . . . 107
Powering off and on Continuous Access XP components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Planned outage of MCUs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Planned outage of RCUs or remote copy connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Planned outage of MCUs and RCUs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Continuous Access XP disaster recovery operations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Preparing for disaster recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Considering the P-VOL fence-level setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
Setting the fence level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Transferring sense information between sites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
File and database recovery procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Switching operations to remote sites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Analyzing currency of Continuous Access XP Synchronous S-VOLs . . . . . . . . . . . . . . . . . . . . . . . 112
Analyzing consistency of Continuous Access XP Asynchronous S-VOLs . . . . . . . . . . . . . . . . . . . . 112
Transferring operations back to primary sites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Resuming normal operations at primary sites. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Error codes and messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Continuous Access XP error codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Service Information Messages (SIMs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Pinned track recovery for Continuous Access XP volumes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Figures
1 Continuous Access XP components for Fibre Channel connections . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2 Remote copy operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3 Selecting and settling Continuous Access XP Async recordsets at the RCU. . . . . . . . . . . . . . . . . . . . . 22
4 Fibre Channel remote copy connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
5 Direct connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
6 Switch connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

6
7 Extender connection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
8 Add RCU and RCU Option panes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
9 Async Option and Add CT Group panes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
10 Shared Continuous Access XP P-VOL/Business Copy XP P-VOL . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
11 Shared Continuous Access XP S-VOL/Business Copy XP P-VOL . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
12 Shared Continuous Access XP/BC P-VOL with shared Continuous Access XP S-VOL/BC P-VOL . . . . . . 43
13 Shared BC S-VOL/Continuous Access XP P-VOL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
14 Copying access attributes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
15 Continuous Access XP main pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
16 Volume list (partial view). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
17 Display Filter pane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
18 RCU Operation pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
19 RCU Operation pane with the MCU&RCU option button selected . . . . . . . . . . . . . . . . . . . . . . . . . . 56
20 RCU Operation pane with the Port option button selected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
21 Asynchronous Operation pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
22 Usage Monitor pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
23 History Operations pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
24 Other Operation pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
25 Option Settings List for the subsystem and the pop-up menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
26 System Option pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
27 RCU Status pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
28 Add RCU pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
29 RCU Option pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
30 RCU Settings Parameter list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
31 RCU Option pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
32 RCU Settings Parameter list (RCU Option) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
33 Fibre Channel interface connections going through switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
34 Add RCU pane used for configuration in Figure 33 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
35 Add Path pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
36 Add SSID pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
37 Changing port types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
38 CT Group Status pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
39 Add CT Group pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
40 CT Group Option pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
41 Consistency Group Settings Parameter list. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
42 Async Option pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
43 Asynchronous Option Settings Parameter list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
44 Display Item pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
45 Pairdisplay pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
46 Paircreate pane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
47 Pair Settings Parameter list (Paircreate) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
48 Pairsplit-r pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
49 Pair Settings Parameter list (Pairsplit-r) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
50 Pairresync pane. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
51 Pair Settings Parameter list (Pairresync). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
52 Pairsplit-S pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
53 Pair Settings Parameter list (Pairsplit-S) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
54 Change Pair Option pane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
55 Pair Settings Parameter list (Pair Option). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
56 Relationship between log file and data file in PAIR status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Tables
1 Recommended and minimum firmware versions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2 Document conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3 RAID-level configurations for Continuous Access XP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4 Continuous Access XP supported RAID level configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5 Sidefile threshold values for Continuous Access XP Asynchronous operations and write pending operations
23
6 Continuous Access XP Asynchronous pair status descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Continuous Access XP user guide for the XP12000/XP10000 7
7 Continuous Access XP split types (PSUS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
8 Consistency status descriptions for split/suspended Continuous Access XP Async S-VOLs . . . . . . . . . . . 28
9 Continuous Access XP suspend types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
10 Continuous Access XP Asynchronous suspension conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
11 Whether non-Continuous Access XP and non-Continuous Access XP Async volumes can be used as Continu-
ous Access XP and Continuous Access XP Async volumes37
12 Host pair status reporting for Continuous Access XP, BC, and Continuous Access XP/BC shared volumes42
13 Data currency of a shared Continuous Access XP/BC volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
14 Access attribute and availability as a Continuous Access XP pair volume . . . . . . . . . . . . . . . . . . . . . . 44
15 VMA setting and availability of Paircreate operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
16 Pair status and availability for LUN Security XP Extension operations . . . . . . . . . . . . . . . . . . . . . . . . . 46
17 Variable access attribute (pair status of Continuous Access XP P-VOL is PAIR or COPY) . . . . . . . . . . . . 46
18 Continuous Access XP functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
19 Volume icons for Continuous Access XP operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
20 Status icons for Continuous Access XP operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
21 Snapshot functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
22 Logical path status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
23 Initial copy pace for calculating initial copy response time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
24 Example settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
25 Remote copy I/O statistics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
26 Disk array performance conditions and recommendations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
27 Fence-level settings on Continuous Access XP Sync P-VOLs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
28 Determining Continuous Access XP Synchronous S-VOL currency based on its pair status and P-VOL fence-lev-
el setting113
29 Determining Continuous Access XP Async S-VOL consistency based on its pair status and consistency status
114

8

Continuous Access XP user guide for the XP12000/XP10000 9
About this guide
This guide provides information about the following:
•”Overview of Continuous Access XP operations” on page 13
•”Preparing for Continuous Access XP operations” on page 31
•”Starting Continuous Access XP” on page 48
•”Performing Continuous Access XP configuration operations” on page 62
•”Continuous Access XP disaster recovery operations” on page 108
•”Error codes and messages” on page 114
•”Pinned track recovery for Continuous Access XP volumes” on page 115
Intended audience
This guide is intended for customers and HP-authorized service providers with knowledge of the following:
•Disk array hardware and software
•Data processing and RAID storage subsystems and their basic functions
NOTE: The functions described in this manual may be limited, depending on your assigned level of user
access. Some users will have read-only access while others will have limited or full array access. For
additional information on users and user groups, please see the HP StorageWorks XP Remote Web
Console user guide.
Prerequisites
Prerequisites for using this product include:
•Installation of the HP StorageWorks disk array(s)
•Installation of the license key for this product
Firmware versions
The recommended firmware versions shown in Table 1 provide the optimal level of support for the
features provided with this product. Older firmware versions can be used; however, product features
enabled with newer firmware will not appear.
Related documentation
In addition to this guide, please refer to other documents for this product:
•HP StorageWorks XP Remote Web Console user guide for XP12000/XP10000
•HP StorageWorks Auto LUN XP user guide for the XP12000/XP10000
•HP StorageWorks Business Copy XP user guide for the XP12000/XP10000
•HP StorageWorks Cache LUN XP user guide for the XP12000/XP10000
•HP StorageWorks External Storage XP user guide
•HP StorageWorks LUN Configuration and Security Manager XP user guide for the
XP12000/XP10000
•HP StorageWorks LUN Security XP Extension user guide
Table 1 Recommended and minimum firmware versions
XP disk array Minimum Recommended
XP12000 50-05-46-00/00 or later 50-06-xx-00/00 or later
XP10000 50-05-46-00/00 or later 50-06-xx-00/00 or later

10
•HP StorageWorks Performance Control user guide
•HP StorageWorks XP Disk/Cache Partition user guide
You can find these documents at http://www.hp.com/support/rwc/manuals
Document conventions and symbols
CAUTION: Indicates that failure to follow directions could result in damage to equipment or data.
IMPORTANT: Provides clarifying information or specific instructions.
NOTE: Provides additional information.
TIP: Provides helpful hints and shortcuts.
HP technical support
Telephone numbers for worldwide technical support are listed on the HP support web site:
http://www.hp.com/support/.
Collect the following information before calling:
•Technical support registration number (if applicable)
•Product serial numbers
•Product model names and numbers
•Applicable error messages
•Operating system type and revision level
•Detailed, specific questions
For continuous quality improvement, calls may be recorded or monitored.
Table 2 Document conventions
Convention Element
Blue text: Table 1 Cross-reference links and e-mail addresses
Blue, underlined text: (http://www.hp.com) Web site addresses
Bold text •Keys that are pressed
•Text typed into a GUI element, such as a box
•GUI elements that are clicked or selected, such as
menu and list items, buttons, and check boxes
Italic text Text emphasis
Monospace text •File and directory names
•System output
•Code
•Commands, their arguments, and argument values
Monospace, italic text •Code variables
•Command variables
Monospace, bold text Emphasized monospace text

Continuous Access XP user guide for the XP12000/XP10000 11
Subscription service
HP strongly recommends that customers register online using the Subscriber’s choice web site at
http://www.hp.com/go/e-updates.
Subscribing to this service provides you with e-mail updates on the latest product enhancements, newest
driver versions, and firmware documentation updates as well as instant access to numerous other product
resources.
After subscribing, locate your products by selecting Business support and then Storage under Product
Category.
Helpful web sites
For additional information, see the following HP web sites:
•http://www.hp.com
•http://www.hp.com/go/storage
•http://www.docs.hp.com
•http://www.hp.com/support/rwc/manuals

12

Continuous Access XP user guide for the XP12000/XP10000 13
1 Continuous Access XP for the XP12000/XP10000
HP StorageWorks Continuous Access XP creates and maintains duplicate copies of user data from a local
disk array on a remote disk array. These copies are useful for data duplication, backup, and disaster
recovery. Continuous Access XP has synchronous and asynchronous copy modes to accommodate a wide
variety of user requirements and data copy or movement scenarios. Continuous Access XP is used for open
systems data.
NOTE: This user guide applies only to Continuous Access XP Synchronous and Continuous Access XP
Asynchronous. It does not apply to Continuous Access XP Journal. For information about Continuous
Access XP Journal, see the HP StorageWorks Continuous Access XP Journal user guide.
If a system failure or disaster occurs at the primary (main) site, Continuous Access XP simplifies and
expedites disaster recovery procedures.
Continuous Access XP operations are nondisruptive and allow the primary (main) volume of each
Continuous Access XP volume pair to remain online to all hosts for read and write I/O operations. After
operations are established, Continuous Access XP operations continue unattended to provide continuous,
real-time data backup. Continuous Access XP operations can be performed across distances of up to 500
meters with a direct connection, 10 km (6.6 miles) using single-mode longwave optical fibre cables in a
switch configuration, 30 km (18.6 miles) using single-mode fiber with long-haul lasers in a switched
connection, and up to 100 km using DWDM in a switched configuration. Long-distance solutions are
provided, based on user requirements and workload characteristics, using approved channel extenders
and communication lines.
Continuous Access XP operations can be performed with Business Copy XP operations (see ”Overview of
Continuous Access XP operations” on page 13) to provide multiple internal copies of Continuous Access
XP volumes. Continuous Access XP also supports LU Size Expansion (LUSE), Custom Volume Size (CVS),
and HP Cache LUN volumes. See ”Combining Continuous Access XP with other data management
operations” on page 37 for more information.
Overview of Continuous Access XP operations
Continuous Access XP provides a storage-based hardware solution for disaster recovery, which enables
fast and accurate system recovery. After Continuous Access XP operations are established, duplicate
copies of data are automatically maintained for backup and disaster recovery purposes. During normal
Continuous Access XP operations, primary volumes remain online to all hosts and continue processing
read and write I/O operations. If a disaster or system failure occurs, the secondary copy of data can be
rapidly invoked to allow recovery with a very high level of data integrity. Continuous Access XP can also
be used for data duplication and migration tasks.
Continuous Access XP Synchronous provides volume-based real-time data replication and is ideal for
high-priority data backup, duplication, and migration tasks. If a disaster or system failure occurs at the
primary site, secondary Continuous Access XP Synchronous data can be rapidly invoked to allow recovery
at the volume level with an extremely high level of data integrity and currency. Up to a distance of
approximately 7-9 km, Continuous Access XP Synchronous provides the highest theoretical throughput.
Continuous Access XP Asynchronous represents a unique and outstanding disaster recovery solution for
large amounts of data spanning multiple volumes. The Continuous Access XP Asynchronous group-based
update sequence consistency solution enables fast and accurate database recovery after a disaster,
without time-consuming data recovery procedures. Continuous Access XP Asynchronous (Continuous
Access XP Async) volume groups at the remote site can be recovered with full update sequence
consistency, but data currency might be behind the primary site due to the asynchronous remote copy
operations.
Continuous Access XP Asynchronous provides update sequence consistency for user-defined groups of
volumes (such as large databases) and protection for write-dependent applications if a disaster occurs.
Beyond a distance of 7-9 km, Continuous Access XP Asynchronous provides the highest possible theoretical
throughput.

14 Continuous Access XP for the XP12000/XP10000
This overview of Continuous Access XP operations describes:
•”Components” on page 14
•”Remote copy operations” on page 19
•”Continuous Access XP Asynchronous recordset operations” on page 21
•”Continuous Access XP Asynchronous consistency group operations” on page 23
•”Continuous Access XP volume pair status” on page 25
Components
Continuous Access XP operations involve the XP12000/XP10000 at a primary and secondary (remote)
site, physical communications paths between these disk arrays, and Command View XP or XP Remote
Web Console. Continuous Access XP copies online data at the primary site to volumes at the secondary
site via dedicated Fibre Channel remote copy connections.
Host failover software is required for effective disaster recovery with Continuous Access XP.
Figure 1 shows Continuous Access XP components and the following functions:
•”XP12000/XP10000” on page 14
•”Main and remote control units (MCUs and RCUs)” on page 15
•”Volume pairs (P-VOLs and S-VOLs)” on page 16
•”Continuous Access XP Asynchronous consistency groups” on page 16
•”Remote copy connections” on page 17
•”Initiator ports and RCU target ports” on page 17
•”Remote control ports (RCPs) and local control ports (LCPs)” on page 18
•”Command View XP management station or XP Remote Web Console” on page 18
•”Host failover software” on page 18
u
Figure 1 Continuous Access XP components for Fibre Channel connections
XP12000/XP10000
Continuous Access XP operations involve primary (main) disk arrays and secondary (remote) disk arrays
(MCUs and RCUs). This document describes Continuous Access XP operations in which the main disk array
is an XP12000/XP10000 and the remote disk array is an XP12000/XP10000. MCUs contain
Continuous Access XP primary volumes (P-VOLs), which contain original data and are online to the hosts.
RCUs contain Continuous Access XP secondary volumes (S-VOLs), which are synchronous or asynchronous

Continuous Access XP user guide for the XP12000/XP10000 15
copies of the P-VOLs. Continuous Access XP supports all CU images and logical volumes of the disk array
and all physical hard drive options. Continuous Access XP supports RAID1, RAID5, and RAID6
configurations for the XP12000/XP10000.
Table 3 shows RAID-level configurations for Continuous Access XP.
To provide greater flexibility and enable the disk array to be tailored to unique customer operating
requirements, additional operational parameters, or optional modes, are available for the disk array. At
installation, modes are set to their default values, so discuss these settings with your HP support team.
Modes can only be changed by your HP support team representative.
Contact your HP account support representative for the latest mode information.
Main and remote control units (MCUs and RCUs)
The main control unit (MCU) and remote control unit (RCU) control Continuous Access XP operations:
•The MCU is the control unit in the primary disk array that controls the P-VOLs of the Continuous Access
XP volume pairs. For Command View XP, the management station must be LAN-attached to the MCU of
each Continuous Access XP pair. For XP Remote Web Console and Command View XP, you need
connectivity between the array managed in the environment and the Web clients used to manage
them. The MCU communicates with the RCU via dedicated Fibre Channel remote copy connections.
The MCU controls host I/O operations to the Continuous Access XP P-VOLs and Continuous Access XP
initial copy and remote copy operations between the P-VOLs and S-VOLs. The MCU also manages
Continuous Access XP pair status and configuration information.
•The RCU is the CU in the remote disk array that controls the S-VOLs of the Continuous Access XP
volume pairs. The RCU assists in managing Continuous Access XP pair status and configuration (for
example, rejects write I/Os to Continuous Access XP S-VOLs). The RCU executes remote copy
operations issued by the MCU. For Command View XP, the management station must be LAN-attached
to the RCU of each Continuous Access XP pair. For XP Remote Web Console and Command View XP,
you need connectivity between the array managed in the environment and the Web clients used to
manage them. The RCUs should also be attached to a host system to allow sense information to be
reported if a problem with a secondary volume or remote disk array occurs and provide disaster
recovery capabilities.
You can define the MCU and RCU whether or not you specify the CU image. To define the MCU and RCU
and specify the CU image, specify the desired CU image. To define the MCU and RCU without specifying
the CU image, specify CU Free. For more information, see ”Registering RCUs (Add RCU)” on page 66.
The MCU and RCU can be defined separately for each Continuous Access XP volume pair. The
XP12000/XP10000 CU can function simultaneously as an MCU for one or more P-VOLs and as an RCU
for one or more S-VOLs, provided the remote copy connections and Fibre Channel or serial interface ports
are properly configured. The XP12000/XP10000 provides up to 32 logical CU images (0-1F), with each
CU image controlling up to 256 logical devices (LDEVs). To define the MCU and RCU and specify the CU
image, use Continuous Access XP to select the desired CU image in the connected MCU and specify the
desired CU image in the RCU. Continuous Access XP operations can be performed on all LDEVs except the
XP12000/XP10000 command device.
Table 3 RAID-level configurations for Continuous Access XP
RAID level of P-VOL RAID level of S-VOL
RAID1 RAID5 RAID6
RAID1 Supported Supported Supported
RAID5 Supported Supported Supported
RAID6 Supported Supported Supported

16 Continuous Access XP for the XP12000/XP10000
NOTE: When serial interface connections are used for remote copy operations, controller emulation of
the connected ports of the MCU and RCU can be different. However, when the MCU and RCU are
connected to the same host, controller emulation of the host-connected ports of the MCU and RCU must be
the same.
Volume pairs (P-VOLs and S-VOLs)
Continuous Access XP performs remote copy operations for logical volume pairs you create. Each
Continuous Access XP pair consists of one primary volume (P-VOL) and one secondary volume (S-VOL),
which can be in the same disk array (synchronous only) or different disk arrays. The Continuous Access XP
P-VOLs are primary volumes (LUs) containing original data, and the Continuous Access XP S-VOLs are
secondary or mirrored volumes (LUs) containing replicated or duplicate data. Volumes are copied on an
Open volume basis, and logical volumes should have the same format and capacity (SCSI path definition
is required). During normal Continuous Access XP operations, the P-VOL remains available to all hosts at
all times for read and write I/O operations. During normal Continuous Access XP operations, the RCU
rejects all host-requested write I/Os for the S-VOLs. The S-VOL write enable option allows write access to
an S-VOL while the pair is split, and uses the S-VOL and P-VOL cylinder maps to resynchronize the pair (see
”S-VOL write option” on page 20).
Continuous Access XP supports basic logical unit (LU) types available on the XP12000/XP10000.
Continuous Access XP also supports Volume Manager, CVS, and Cache LUN XP features, ensuring that all
user data can be backed up or duplicated. See ”Logical unit (LU) types” on page 31 for further information
about LU requirements and support.
Continuous Access XP supports a maximum of 8,192 Continuous Access XP pairs (entire RCU). When
Continuous Access XP pairs include size-expanded LUs, the maximum number of pairs decreases. When
the RAID Manager command device is defined, the maximum number of Continuous Access XP pairs in
the XP12000/XP10000 is 8,191.
Continuous Access XP supports the following RAID level configurations.
Continuous Access XP Asynchronous consistency groups
A Continuous Access XP Asynchronous consistency group is a user-defined set of volume pairs across
which update sequence consistency is maintained and ensured at the remote site. Each Continuous Access
XP Async volume pair must be assigned to a consistency group. Continuous Access XP can configure up to
128 consistency groups (0-7F) for each MCU and provides group-based operations for consistency groups
(for example, split and resync group). Use consistency groups to maintain update sequence consistency for
databases spanning multiple volumes, allowing immediate database recovery at the remote site when
needed. See ”Continuous Access XP Asynchronous consistency group operations” on page 23 for further
information.
Table 4 Continuous Access XP supported RAID level configurations
For P-VOL For S-VOL
RAID 1 RAID 1
RAID 1 RAID 6
RAID 5 RAID 5
RAID 1 RAID 5
RAID 5 RAID 1
RAID 5 RAID 6
RAID 6 RAID 1
RAID 6 RAID 5
RAID 6 RAID 6

Continuous Access XP user guide for the XP12000/XP10000 17
Only Continuous Access XP Asynchronous pairs belonging to the same CLPR can be allocated to one
Continuous Access XP consistency group. For more information about CLPRs, see the HP StorageWorks XP
Disk/Cache Partition user guide.
Remote copy connections
Remote copy connections are physical paths MCUs use to communicate with RCUs. The number of
physical paths in the MCU is limited to eight per logical CU image. MCUs and RCUs are connected via
Fibre Channel interface cables.
When Fibre Channel interface connections are used, switches are required for distances greater than 0.5
km (1,640 feet). Distances up to 1.5 km (4,920 feet, 0.93 miles) are supported with dual switches utilizing
shortwave connections. Distances up to 10 km (6.2 miles) are supported using dual switches with
longwave connections. Distances up to 30 km (18.6 miles) are supported using dual switches with
longhaul connections. Distances up to 100 km are supported by using dual switches with DWDM. See
”Fibre Channel remote copy connections” on page 34 for further information about installing and
configuring Fibre Channel remote copy connections.
The MCU-to-RCU remote copy configuration for Continuous Access XP Asynchronous has different
requirements than the Continuous Access XP Synchronous configuration, as follows:
•Continuous Access XP Synchronous supports 1-to-n and n-to-1 remote copy connections (n≤4). One
MCU can be connected to as many as four RCUs. One RCU can be connected to as many as four
MCUs (one MCU/RCU = one physical CU, including all sixteen CU images).
•Continuous Access XP Asynchronous supports 1-to-1 remote copy connections within the same
consistency group. P-VOLs and S-VOLs of pairs in a consistency group must be within one physical
MCU and one physical RCU. This configuration ensures backup integrity for a data set spread across
multiple volumes within one XP12000/XP10000 (such as large databases).
Continuous Access XP Asynchronous 1-to-n and n-to-1 (n ≤4) configurations (one main disk array and
multiple remote disk arrays) are valid for Continuous Access XP Asynchronous if all volumes belonging
to a single consistency group are only 1-to-1.
•With direct connect Fibre Channel (no switch), fibre remote copy supports 1-to-1 remote copy
connections. One XP12000/XP10000 as an MCU can be connected to only one XP12000/XP10000
as an RCU via optical fibre cables. For CU images within one XP12000/XP10000, 1-to-4 and 4-to-1
remote copy connections are supported via direct connects or an FC switch.
HP strongly recommends you establish at least two independent remote copy connections (one per cluster)
between each MCU and RCU to provide hardware redundancy for this critical communications path.
NOTE: To recover data from a disaster, prepare the RCU-MCU paths in addition to the usual MCU-RCU
paths. For more information, see ”Registering RCUs (Add RCU)” on page 66.
When you set the RCU-MCU path, you must also specify:
•The same combination of CU images as when you set the MCU-RCU path if you set the MCU-RCU path
and specify the CU image.
•CU Free if you set the MCU-RCU path and specify CU Free.
For more information, see ”Preparing for disaster recovery” on page 108.
Initiator ports and RCU target ports
Initiator ports are dedicated Fibre Channel interface ports on the main disk array (MCU) to which RCUs
(RCU target ports) are connected. Initiator ports connect to RCUs to send write I/O operations directly to
RCUs. You can configure Fibre Channel interface ports of the XP12000/XP10000 as initiator ports. Use
the Port Change operation (see ”Port change operation” on page 76) to change the configuration of the
XP12000/XP10000 Fibre Channel ports (ordinary target port, initiator port, or RCU target port) as
needed.

18 Continuous Access XP for the XP12000/XP10000
NOTE: Initiator ports cannot communicate with hosts, but are used exclusively as Continuous Access XP
talkers. Ordinary target ports can be used only for host connect (not for Continuous Access XP).
RCU target ports are (Continuous Access XP) dedicated Fibre Channel interface ports on the remote disk
array (RCU) to which MCUs (initiator ports) are connected. You can configure Fibre Channel interface
ports of the XP12000/XP10000 as RCU target ports. For performance reasons, RCU target ports should
not be shared with host connects.
Remote control ports (RCPs) and local control ports (LCPs)
Remote control ports (RCPs) are dedicated serial interface ports on the MCU to which RCUs are connected.
RCPs emulate host processor channels, enabling MCUs to send write I/O operations directly to RCUs.
RCPs support the dynamic switching capability provided by ESCDs. You can configure serial interface ports
of the disk array as RCPs. Use Continuous Access XP to change the configuration of disk array serial ports
(LCP or RCP) as needed (see ”Port change operation” on page 76).
Local control ports (LCPs) are used for host processor channel interfaces. All serial interface ports on the
disk array have a default setting of LCP. An RCU port connected to an MCU must be in LCP mode to
receive remote copy I/O operations from the MCU.
Two or more RCPs must be configured before you can add RCUs and create Continuous Access XP volume
pairs. RCPs cannot communicate with host processor channels and are dedicated to Continuous Access XP
operations. Host channel interface paths must be connected to other interface ports on the disk array.
Serial interface ports, 1S-1Z and 2S-2Z, cannot be specified as RCPs.
CHA package ports added to DKA slots cannot be specified as RCPs.
Command View XP management station or XP Remote Web Console
The Command View XP management station is attached to the XP12000/XP10000 on the internal LAN
via a TCP/IP connection. The Command View XP management station communicates with each attached
XP12000/XP10000.
The Command View XP management station at the primary site must be connected to the MCU of each
Continuous Access XP pair. A second Command View XP management station should be installed at the
remote site and connected to the RCUs. With another Command View XP management station at the
remote site, you can modify the Continuous Access XP Asynchronous options of the RCU (for example,
pending update data rate or offloading timer) and access the Continuous Access XP S-VOLs (for example,
to perform media maintenance). To perform Continuous Access XP operations in the reverse direction from
the remote site to the primary site (for example, disaster recovery), Continuous Access XP simplifies and
expedites this process.
Alternatively, you can access XP Remote Web Console directly on the MCUs and RCUs to manage their
respective disk arrays.
Host failover software
Host failover software, which transfers information between host servers at primary and remote sites, is a
critical component of any disaster recovery effort. Host failover is configured using the host failover
software product for the platform (such as Microsoft® Cluster Server or HP Cluster Extension XP),
depending on your installation requirements and standards. Command View XP or XP Remote Web
Console does not provide host failover functions.
When Continuous Access XP is used as a data migration tool, host failover is recommended but not
required. When Continuous Access XP is used as a disaster recovery tool, host failover is required to
ensure effective disaster recovery operations. When a Continuous Access XP pair is suspended due to an
error condition, the MCU generates sense information that should be transferred to the remote site via host
failover software for effective disaster detection and recovery.

Continuous Access XP user guide for the XP12000/XP10000 19
Remote copy operations
There are two types of Continuous Access XP remote copy operations: initial copy and update copy.
Figure 2 Remote copy operations
Initial copy operations
Initial copy operation synchronize P-VOLs and S-VOLs independently of host I/O processes. Initial copy
operations are the same for Continuous Access XP Sync and Continuous Access XP Async pairs.
Continuous Access XP initial copy operations occur when adding a pair (paircreate) or resuming a
split/suspended pair (pairresync). When a new pair is created, the entire contents of the P-VOL are copied
to the S-VOL cylinder by cylinder, except for diagnostic and unassigned alternate tracks. You can select No
Copy for the Initial Copy field of the initial copy parameters, which copies only cylinder #0 to the S-VOL. If
No Copy is selected, you are responsible for ensuring that P-VOLs and S-VOLs are already identical. The
MCU cannot verify the contents of volumes. When a split/suspended pair is resumed (pairresync), only
cylinder #0 and out-of-sync cylinders (updated by write I/Os during split/suspension) are copied to the
S-VOL. When the Continuous Access XP S-VOL write enable function is used, the RCU tracks S-VOL
updates and sends the S-VOL cylinder bitmap to the MCU when the split pair is resumed. In this case the
MCU merges the P-VOL and S-VOL bitmaps to identify out-of-sync cylinders.
For additional flexibility, Continuous Access XP provides the following options for initial copy:
•Use the Initial Copy Pace field of the initial copy parameters to specify how many tracks the Continuous
Access XP initial copy operation copies simultaneously when creating/resuming a Continuous Access
XP pair. This option can only be specified using Continuous Access XP.
•Use the Priority field of the initial copy parameters to specify the order in which initial copy operations
are performed when creating/resuming multiple Continuous Access XP pairs. This option can only be
specified using Continuous Access XP.
•Use the Maximum Initial Copy Activity option to specify maximum number of concurrent initial copy
operations each MCU can perform (not pair-specific). This option can only be specified using
Continuous Access XP.
Update copy operations
Update copy operations occur when the host issues a write I/O operation to the P-VOL of an established
Continuous Access XP pair. Update copy operations duplicate P-VOL write I/Os at the S-VOL to keep the
volume pair synchronized. Continuous Access XP provides two modes for update copy operations:
synchronous and asynchronous. Update copy mode is specified when you add a Continuous Access XP
pair and is unchangeable for the life of the pair.
For synchronous update copy mode, the MCU ensures the P-VOL and S-VOL are synchronized at all times.
When using fence level “data,” the MCU does not return final ending status for the P-VOL write I/O until
the outcome of the P-VOL write and its associated update copy operation at the RCU are known. For
synchronous mode, the MCU starts the update copy operation when it receives:
•A write command whose data length is short enough not to pass the track-end
•Write data to the track-end, whose total length is long enough to pass the track-end
•Write data to the last track for the command
NOTE: No matter how long the write data is, update copy is executed for each track.

20 Continuous Access XP for the XP12000/XP10000
For asynchronous update copy mode, the MCU stores P-VOL updates with additional control information in
cache, and sends updates and control information to the RCU completely independent of host I/O
processes. These updates and their associated control information are called recordsets. The RCU stores
recordsets in cache and performs updates to S-VOLs in the same order as they were performed at MCUs
according to the sequence information stored in the recordset. For more information on recordset
operations, see ”Continuous Access XP Asynchronous recordset operations” on page 21.
Priority of initial and update copy: In both Continuous Access XP Synchronous and Continuous Access XP
Asynchronous, update copy has higher priority than initial copy. However, initial copy is executed based
on copy pace (3 or 15 tracks). Therefore, update copy must wait this interval if initial copy is being
executed. For example, if the copy pace is 15 tracks, the update copy may wait up to 15 tracks (1
cylinder). For Continuous Access XP Asynchronous, update copy is executed asynchronously, but the same
scheduling conflict can occur between the asynchronous update copy (write recordset) and initial copy.
Read and write I/O operations for Continuous Access XP volumes
When an MCU receives a read command for a Continuous Access XP P-VOL, the MCU completes the read
from the P-VOL. The MCU will not read the Continuous Access XP S-VOL over the link if a failure rendered
the P-VOL inaccessible.
When an MCU receives a write command for a Continuous Access XP Synchronous P-VOL with COPY
status and the track has already been copied to the S-VOL, the MCU performs a synchronous update copy
operation to complete the write at the S-VOL. When an MCU receives a write command for a Continuous
Access XP Asynchronous P-VOL with COPY status and the track has already been copied to the S-VOL, the
MCU performs an asynchronous update copy operation.
When an MCU receives a write command for a Continuous Access XP P-VOL with PAIR status, the
user-selected update copy mode (synchronous or asynchronous) determines the sequence of events as
follows:
•Synchronous Mode: The MCU performs the write operation on the P-VOL, starts the update copy
operation for the S-VOL, and reports final ending status to the host only after results of the update copy
operation are known. If the P-VOL write or S-VOL update copy operation fails, the MCU reports a unit
check, and the host system and application program regard that write operation to the P-VOL as failed.
•Asynchronous Mode: The MCU completes P-VOL write operations independently of the associated
update copy operations at the S-VOL. The RCU manages the S-VOL updates according to recordset
information and maintains sequence ordered data consistency for the S-VOLs. If the P-VOL write
operation fails, the MCU reports a unit check and does not create the Continuous Access XP
asynchronous recordset for this operation. If the update copy operation fails, the RCU optionally
suspends the affected pair or all pairs in the consistency group, depending on the type of failure.
When the suspended pair or group is resumed (pairresync), the MCU and RCU negotiate the
resynchronization of the pairs. See ”Continuous Access XP suspend types” on page 28 for further
information about suspended Continuous Access XP Async pairs.
The RCU does not allow a Continuous Access XP S-VOL to be online (mounted) during normal Continuous
Access XP operations and rejects all host-requested write I/O operations for an S-VOL. The special
Continuous Access XP S-VOL write enable option enables write access to an S-VOL while the pair is split
(see ”S-VOL write option” on page 20). The S-VOL write option can be enabled only when you split the
pair from the MCU.
To reduce overhead associated with Continuous Access XP remote copy operations, the
XP12000/XP10000 uses a special write command that is allowed only for Continuous Access XP initial
and update copy operations. This Continuous Access XP command transfers control parameters and
FBA-format data, which includes consecutive updated records in each track, using a single write operation.
This capability eliminates overhead required for performing FBA-to-CKD and CKD-to-FBA conversions.
S-VOL write option
Continuous Access XP provides an S-VOL write option that enables write access to the S-VOL of a split
Continuous Access XP pair. The S-VOL write option can be selected during the pairsplit-r operation and
applies only to the selected pairs. The S-VOL write option can be accessed only when you are connected
to the MCU. When you resync a split Continuous Access XP pair that has the S-VOL write option enabled,