13.1 Chapter Objectives

• Develop and implement backup strategies that meet service-level objectives

• Minimize risks associated with online backups

• Automate backups with DCL command procedures

• Optimize OpenVMS BACKUP performance

13.2 Introduction

Data backup, when viewed from a larger perspective, is saved for the following reasons:

• For data safety

• For business or statutory reasons

To meet cost and resource needs, data saved to near-line or offline storage can be deleted to make more online storage space available. In this chapter we discuss data backup primarily from the safety standpoint.

Your system contains valuable data stored on disk. To prevent data from being lost, you should perform regular backups by copying files to some type of removable media (usually magnetic tape). If files become damaged or lost, you can recover them from backups and restore the system to a usable state.

Performing backups is very time-consuming, but like many forms of insurance, you realize its value when a problem occurs. If your home or car were destroyed and you did not have insurance, the financial impact could be devastating. Similarly, performing anything other than robust backups might save you some time and money now, but will financially ruin you or your organization in the long run. Backups are one of your most important responsibilities; give them the attention they deserve.

Backups provide protection against the following three types of failures:

1. Hardware failures: Although computer systems are relatively reliable, individual components can and do eventually fail. When failures occur, files or entire disks...