Building Disaster Recovery Serviceguard Solutions Using Metrocluster with Continuous Access for P9000 and XP A.11.00

Continuous Access Journal Software User Guide or HP StorageWorks XP24000/XP20000

Continuous Access Journal Software User Guide available at:

http://h20000.www2.hp.com/bizsupport/TechSupport/DocumentIndex.jsp?lang=en&cc=us&

taskId=101&prodClassId=-1&contentType=SupportManual&docIndexId=64255&

prodTypeId=18964&prodSeriesId=4309847.

Figure 33 Configuration of the Delta Resync Operation that utilizes Remote Command Devices

Site 1

CA-jnl

CA-Sync

Site 2

Site 3

S-VOL

Jnl

Vol

Jnl

Vol

P-VOL

Jnl

Vol

CA-Jnl Delta Resync

HP Storage Mirror Unit Descriptors

To setup Raid Manager Configuration for 3DC architecture, “mirror unit descriptors” (MU#) are

used to distinguish and manage an application device group among 3 data centers. A mirror unit

descriptor (MU#) is a special index number available with all volumes that provides an individual

designator for each copy of the volume. The mirror unit descriptor is provided in the Raid Manager

Configuration files to indicate the nature of the copy.

A volume can be represented with seven mirror unit descriptors. Out of seven mirror unit descriptors,

three MU#'s are for local replication copies using Business Copy, and are represented in the HP

Storage RAID Manager (RM) configuration file by the values 0, 1, and 2. The RM configuration

file assumes MU# of 0 when no MU# is specified in the configuration file. However to avoid

confusion, the 0 should be explicitly defined in the configuration for Business Copy.

The fourth MU# can be used for either Continuous Access Synchronous, or Continuous Access

Asynchronous, or Journal. When it is used for Sync/Async, the MU# can be either 0 or left blank.

The remaining three MU#'s are for Continuous Access Journal replication pairs only. These MU#'s

are represented by h1, h2, and h3 values in the RM configuration file.

Figure 34 (page 98) shows all the available mirror unit descriptors for each data device, as well

as the value to use in the HP Storage RAID Manager (RM) configuration file to identify the specific

replication instance for the device and any environment variables (for example, HORCC_MRCF)

necessary to address the Business copy or Continuous Access using RAID Manager.

Overview of Continuous Access 3DC Replication Technology 97