Designing a data backup solution requires many considerations. This book describes various aspects of data backups, such as storage media, types of backups, environments, strategies for design, monitoring, and performance analysis. It also describes two data backup software products, with their configurations, and presents advantages and disadvantages of choosing certain methods over others.

Chapter 1 discusses the basics of data backups, explaining terms such as “full backup,” “incremental backup,” and “differential backup.” It also discusses active archives, offline archives, and the difference between archives and backups. Along with these explanations, the chapter shows some of the associated common mistakes; it ends by discussing general objectives for designing a backup solution. Chapter 2 introduces two backup software options: CommVault Simpana and Symantec NetBackup. The overview of CommVault includes its restoration process, data flow, related media agents, and options; the overview of NetBackup includes server functions, data flows, and process flows.

The next three chapters concern storage media. Chapter 3 describes various types of commonly used tapes and their characteristics--sequential access, small computer system interface (SCSI) connections, the fibre channel protocol (FCP), the estimation of the number of drives, and advantages and disadvantages. The chapter also describes various types of disks in common use and discusses performance aspects in detail. Chapter 4 describes virtual tape libraries (VTLs) and the relation between physical tapes and virtual tapes. It also describes various types of VTL configurations and the limitations, advantages, and difficulties of using virtual media. Chapter 5 is on new media technologies. Deduplication is the process of analyzing data at the sub-file level and storing only those elements that have not already been stored. Various types of deduplications, such as fixed-block deduplication, variable-block deduplication, source-based deduplication, and target-based deduplication, are described. The chapter ends by introducing cloud storage.

The next two chapters address the configurations of the backup software. Chapter 6 discusses the configuration of the CommVault software, including disk types, disk writers, multiplexing, fill/spill versus spill/fill, and data interface pairs. The chapter also discusses how to achieve better performance using CommVault for single-media and multiple-media agents. Chapter 7 focuses on the configuration of the NetBackup software. Various considerations with respect to media servers and storage units are discussed, and the analysis of network resources is introduced. The chapter also introduces configuration elements such as multiplexing and mainstreaming, twinning, buffer tuning, and creating secondary copies.

Chapter 8 presents various backup strategies for applications such as file systems, databases, and mail servers. It explains selective backups, scheduler split backups, block-level backups, and source-based deduplication strategies for backing up file systems. It introduces snapshot backups, split-mirror backups, and hot and cold backups of databases, and discusses backups in a structured query language (SQL) server and in Oracle databases. The chapter also describes backups in Exchange and Lotus Notes mail servers. Chapter 9 is devoted to backup environments: offsite backup as a service, single and multiple media, remote office deployments, and long-distance backups. Chapter 10, on monitoring backups, introduces various monitoring measurements, including successes and failures, client backup speed, and server central processing unit (CPU)/memory/network utilizations. The chapter also presents the advantages and disadvantages of obtaining monitoring data from backup software, third parties, and in-house. The last chapter (11) contains a brief summary.

The book is descriptive and requires only an elementary knowledge of mathematics. Readers are expected to have a general understanding of computer organization. The book covers a wide range of data backups. System administrators, database administrators, architects, and other professionals responsible for backing up data will find the book very useful. It is also good additional reading for undergraduate students taking courses on operating systems and databases.