HP StorageWorks XP24000 Continuous Access Software User and Reference Guide, v01 (T5278-96002, June 2007)

5 Performing Continuous A ccess

Pair Operations

Preparing for Continuous Access Pair Operations

Before starting Continuous Access operations, you must consider the relative impor tance of storage system

I/O performance and disaster recovery pre paration. A s described in “Other Operations” on page 93,

remote copy operations can affect the I/O performance of the MCUs and RCUs. Continuous Access

provides many options (RCU options, initial copy options, pair options, g roup options, async options)

which allow you to control the impact of Continuous Access operations on I/O performance. These

options can be set separately for each pair, for each Continuous Access Asynchronous group, and

for each MCU to provide maximum ﬂexibility. You can select options which minimize the impact

of Continuous Access operations on storage system performance, or options which maximize the

effectiveness of Continuous Access operations to ensure the best level of backup data integrity.

System-level factors (for example, number of paths) can also affect Continuous Access operations and

storagesystem performance(see“Other Operations”onpage93).

For Continuous Access disaster recovery operations, you should m ake sure that the RCUs are attached to

host server to enable reporting of sense i nformation and transfer of host failover information. If the

remote site is unattended, you should at tach the RCUs to a host server at the main site, so that the system

administrator can monitor the operational condition of the RCUs.

To p repare for Continuous Access pair operations, you need to identify the volumes (by por t, GID (host

group number), and LUN, and/or by LDEV ID) for which you want to establish Continuous Access

remote copy operations. You should identify volumes which are required for system operations as well

as volumes which contain important data to be backed up (for example, DB log ﬁles) . Copying these

volumes to the remote site will enable faster disaster recovery than maintaining a current version of these

ﬁles at the remote site. For large d a tabases which span multiple volumes, you should plan to establish a

Continuous Access Asynchronous consistency group for each database, so that the update sequence

consistency of the database c an be ensured at the remote site.

You can start creating the Continuous Access pairs as soon as you have:

• Identiﬁed the volumes (LUs) which will become the Continuous Access P-VOLs (and S -VOLs),

• Ensured that all system and Continuous Access requirements

have been met (see “System Requirements”onpage43and

“Requirements and Restrictions for Using Continuous Access”onpage44),

•

Completed hardware and software installation (see “Installing the Hardware”onpage46and

“Enabling Continuous Access Options”onpage49),and

• Conﬁguredthe MCUs andRCUsfor Continuous Access operations (see

“Conﬁguring the MCUs and RCUs for Continuous Access O perations” on page 49).

If you will be using the Continuous Access software to perform Continuous Access op erations, the MCU

of each Continuous Access pair must be LAN-attached to the Remote Web Console computer. You should

also attach all RCUs to a Remote Web Console computer via a separate L AN at the remote site. If you

will be using RAID Manager commands instead of the Continuous Access software, contact your HP

service representative for information on Continuous Access conﬁguration services.

Operation Window

Pair Operation window (see Figure 42 on page 100) displays the Continuous Access pair information

or the

connected storage system and allows you to perform all Continuous Access pair operations.

XP24000ContinuousAccessSoftwareUserand ReferenceGuide