Using xp continuous access, Point-in-time (pit) data – HP StorageWorks XP Remote Web Console Software User Manual
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d.
To keep the volumes synchronized, establish the same XP Continuous Access pair(s) in
the reverse direction using the None initial copy option (see
). If the original P-VOL(s) will be temporarily unavailable for update copy
operations, you can split the new pair(s) (pairsplit-r) so that the new MCU keeps track of
the changes.
e.
Start the applications with the S-VOL(s). When the original P-VOL(s) become available,
you can resynchronize the pair(s) (see
“Resynchronizing XP Continuous Access Pairs”
).
The data migration has the possibility that the performance decreases and the utilization rates rises
as well as the XP Continuous Access synchronous.
Point-in-Time (PiT) Data Duplication Using XP Continuous Access
Asynchronous
XP Continuous Access Asynchronous enables you to make Point-in-Time (PiT) duplicates of groups
of volumes. The XP Continuous Access Asynchronous Group and Drain pairsplit options can be
used together to create a PiT copy, relative to an application, of an entire XP Continuous Access
Asynchronous consistency group of volumes. To produce a PiT duplicate of an existing XP Continuous
Access Asynchronous consistency group:
1.
Stop all host updates to all XP Continuous Access Asynchronous P-VOLs in the group.
2.
After all P-VOL updates have completed, split the XP Continuous Access Asynchronous group
using the Group and Drain pairsplit options. If you are splitting the group at the main site,
issue the pairsplit-r/group command to one P-VOL in the MCU. If you are splitting the group
at the remote site, issue the pairsplit-r/group command to one S-VOL in the RCU.
The copy pending timeout setting for the group determines the maximum amount of time that
the pairsplit-r/drain operation can take (see description of Drain above).
3.
When the status of all XP Continuous Access Asynchronous pairs in the group has changed
to PSUS, the duplicate set of volumes is complete. If desired, you can restart the application
at the main site.
Using XP Continuous Access for Disaster Recovery Operations
The type of disaster and the status of the XP Continuous Access pairs will determine the best
approach for disaster recovery. For example, if all XP Continuous Access pairs are in the PAIR
state when a total system failure occurs at a single point in time, the S-VOLs are current and recovery
is straightforward. Unfortunately, some disasters are not so orderly and involve intermittent or
gradual failures occurring over a longer period of time. The user should anticipate and plan for
all types of failures and disasters.
The major steps in preparing for disaster recovery are:
1.
Identify the volumes and groups that contain important files and data for disaster recovery. In
addition to supporting XP Continuous Access remote copy operations as well as RAID Manager
commands, the storage system provides battery-backed nonvolatile duplexed cache, full
hardware redundancy, dynamic sparing, and an advanced RAID-5 implementation to ensure
full data integrity in the event of a sudden power outage or other failure.
2.
Install the Remote Web Console computer and XP Continuous Access hardware and software,
and establish XP Continuous Access operations for the volumes and groups identified in step
1. Make sure to select the proper CUs/ports to access the desired volumes. See
for XP Continuous Access installation instructions. See
XP Continuous Access Configuration Operations” (page 85)
for instructions on performing XP
Continuous Access configuration operations. See
“Preparing for XP Continuous Access
for instructions on performing XP Continuous Access pair operations.
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Usage Scenarios