HP StorageWorks XP Remote Web Console Software - Manual (Page 66)

3DC cascading configuration where three XP Continuous Access Journal sites are combined. In
this configuration, there are three sites:
•
An XP Continuous Access Journal primary site (Primary site whose mirror ID is an arbitrary
number M)
•
An XP Continuous Access Journal intermediate site (Secondary site whose mirror ID is an
arbitrary number M, and primary site whose mirror ID is an arbitrary number N)
•
An XP Continuous Access Journal secondary site (Secondary site whose mirror ID is an arbitrary
number N)
Figure 21 Cascading Configuration Combining Three XP Continuous Access Journal Sites
The data in the primary data volume is written to the secondary data volume asynchronously when
writing to the host. Therefore, even if there is a long distance between the XP Continuous Access
Journal primary site and the XP Continuous Access Journal secondary site, the performance is
maintained.
Setup Procedure
To set up a 3DC cascading configuration using three XP Continuous Access Journal sites using
RAID Manager, use the following procedure:
1.
Install XP Continuous Access Journal and configure ports.
2. In the XP Continuous Access Journal primary storage system and the secondary storage system,
set the system option mode 767 to ON.
NOTE: The mode 767 must be set to ON for storage systems in three sites.
3. Configure XP Continuous Access Journal journal groups.
NOTE: The journal groups must be configured for storage systems in three sites.
4. Create an XP Continuous Access Journal pair of the first mirror in the primary site. When
creating an XP Continuous Access Journal pair, make sure to select a value from 0 to 3 as the
mirror ID.
5. Wait until the status of the XP Continuous Access Journal pair becomes PAIR.
6. Create an XP Continuous Access Journal pair of the second mirror in the intermediate site.
Specify the secondary journal group and the secondary data volume used for the first mirror
66 Preparing for XP Continuous Access Journal Operations