Mainframe Enablers TimeFinder SnapVX and zDP 8.5 Product Guide

Overview

Data Protector for z Systems (zDP) delivers the capability to recover from logical data corruption with minimal data loss. zDP provides multiple, frequent, consistent point-in-time copies of data in an automated fashion. From the point-in-time copies, an application level recovery can be conducted, or the environment can be restored to a point before the logical corruption.

By providing easy access to multiple different point-in-time copies of data (with a granularity of minutes), precise remediation of logical data corruption can be performed using application-based recovery procedures at the dataset level. zDP results in minimal data loss compared to the previous method of restoring data from daily or weekly backups. This is important for non-DBMS data, which does not have the granular recovery options that are provided by log files and image copies that are associated with database management systems.

zDP enables you to create and manage multiple point-in-time snapshots of volumes. A snapshot is a pointer-based, point-in-time image of a single volume. These point-in-time copies are created using the SnapVX feature of PowerMaxOS 5978 and HYPERMAX OS 5977. SnapVX is a space-efficient method for making volume-level snapshots of thin devices and consuming additional storage capacity only when updates are made to the source volume.

SnapVX provides targetless snapshot capabilities. There is no need to copy each snapshot to a target volume as SnapVX separates the capturing of a point-in-time copy from its usage. Capturing a point-in-time copy does not require a target volume. Using a point-in-time copy from a host requires linking the snapshot to a target volume. One snapshot of each volume across a group of volumes is termed a snapset. You can make multiple snapshots of each source volume. zDP supports creating snapshots on both CKD and FBA devices, with the exception of FBA devices used in SRDF Metro configurations.

You can link, unlink, and relink snapshots to the same set of target volumes thus having the flexibility in the point-in-time copy that is presented on a single set of target devices. These snapshots share allocations to the same track image whenever possible while ensuring they each continue to represent a unique point-in-time image of the source volume. Despite the space efficiency that is achieved through shared allocation to unchanged data, additional capacity is required to preserve the preupdate images of changed tracks captured by each point-in-time snapshot.