Hitachi MP-96RD625-01 manual Secondary site for URz

•Secondary site for URz

TCz Synchronous (short distance)

P-VOL/Prm. data VOL

Primary Master

siteJNLVOL

P-VOL: primary volume

S-VOL: secondary volume

Prm. data VOL: primary data volume Sec. data VOL secondary data volume JNLVOL: journal volume

TCz Synchronous secondary site

S-VOL		URz
		(long distance)
	JNLVOL	(for use as an alternative)

Sec. data

VOL

URz	Restore	URz
(long distance)	JNLVOL	secondary site

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.

3-40 Chapter 3 Preparing for Universal Replicator z/OS Operations

Hitachi Universal Replicator for IBM /OS User’s Guide