HP StorageWorks XP Remote Web Console Software - Manual (Page 106)

3-40 Chapter 3 Preparing for Universal Replicator z/OS Operations
Hitachi Universal Replicator for IBM /OS User’s Guide
• Secondary site for URz
Master
JNLVOL
Restore
JNLVOL
Primary
site
URz
secondary site
Sec. data
VOL
S-VOL
JNLVOL
TCz Synchronous
(short distance)
URz
(long distance)
(for use as an alternative)
TCz Synchronous
secondary site
P-VOL: primary volume
S-VOL: secondary volume
Prm. data VOL: primary data volume
Sec. data VOL secondary data volume
JNLVOL: journal volume
P-VOL/Prm.
data VOL
URz
(long distance)
Figure 3-24 3DC Multi-target Configuration (Combining URz with TCz
Synchronous)
In this configuration, the primary volume in the primary site is paired with the
secondary volume for TCz Synchronous. This primary volume is also paired
with the secondary volume for URz. If a host in the primary site writes data to
the primary volume, the data will be written to the TCz Synchronous
secondary volume in real time, synchronously with writing from the host. The
data will also be written to the URz secondary data volume, asynchronously
with writing from the host. Update sequence consistency will be maintained
with the URz secondary data volume.
Since writing from the URz primary volume to the URz secondary volume is
performed asynchronously with writing from the host to the primary volume,
this configuration can prevent delay in response to the host even if the URz
primary site and the URz secondary site are far from each other.
In addition, you can create the URz pair for delta resync operation in 3DC
multi-target configuration, by specifying TCz Synchronous R-VOL in the TCz
Synchronous secondary site as the URz primary data volume, and by
specifying the volume in the URz secondary site as the URz secondary data
volume. If you create the URz pair for delta resync operation, you can
resynchronize the URz pair by using journal data in the TCz Synchronous
secondary site when a failure occurs in the primary site.