Overview

What This Chapter Will Do For You

This chapter looks at essential techniques and technologies for protecting and maintaining access to data. Some items you will learn about in this chapter include:

• All data is not equal in value so why spend the same amount to protect it?

• RAID and mirroring are not replacements for backup to some other medium

• How much downtime and data loss can you afford?

• The importance of compression to reduce storage and networking costs

• Alternative, cost-saving technologies for long-term data protection and retention

12.1 Overview

Data protection, for those not involved with it, may be perceived as an expense item that does not add value to the business. For those who have not experienced loss of data, whether due to accidental deletion, data corruption, theft, or by other means, there may be a tendency to take data protection for granted. This chapter takes a look at some techniques supported and facilitated by storage networks to protect and maintain accessibility to data.

12.2 Protecting data accessibility

Availability is the combination of all components that make up a solution from the server, application, storage subsystem, network, and storage interfaces. While redundancy and high availability of a single component are important, particularly to contain faults, it is the combination of all components that determines how availability should be looked at.

Some approaches to protecting data include:

• Logical and physical security (refer to Chapter 13)

• Device and component media redundancy

• Data mirroring, replication (local and remote)

• Backup, restore, archiving,...