Backup & Recovery is an updated version of a book Preston wrote seven years ago called Unix Backup and Recovery. At least 75% of the material is new. "A lot has changed since then," writes Preston. "The biggest change has been the proliferation of Windows, Mac OS, Exchange and SQL Server in the data center." He adds that the biggest change for him has been what's happened beyond the "traditional" backup and recovery applications. Hence the book's emphasis on tips, tricks and neat hacks he's collected over the years from his consulting work, Internet postings and user-group blogs; they're shortcuts that make backup jobs easier and less hands-on.
Yet Preston readily acknowledges the obvious: Commercial backup products contain ways to solve problems "unsolvable with open-source tools." Though he doesn't review or compare commercial backup products (that's the next book he's working on), he discusses what to look for in a commercial product and lists questions to help readers determine whether a particular product is a good fit for their storage environment.
Preston's backup philosophy has changed since his earlier book: "It's all about disk--especially for smaller shops," he writes. While he doesn't proclaim tape dead, he does play up the advantages of alternative disk technologies, such as virtual tape libraries, virtual tape cartridges and clustered file systems.
But in spite of Preston's recent love affair with disk, he only devotes about three-quarters of a page in one section and half a page in another section of his 729-page book to one of the most promising new technologies for dramatically reducing the amount of data stored on disk: deduplication. It's almost as if Preston overlooked the topic in his original manuscript and hastily added short mentions of it just before going to press. And the sections on snapshots and continuous data protection systems just scratch the surface of these increasingly popular backup technologies.
Quibbles aside, backup and recovery are big subjects that are growing bigger every day. Preston and his hired contributors--about 250 pages were written by experts of some of the operating systems and database platforms covered in this book--have done an outstanding job. There's also material on archiving, disaster recovery and storage security because backups are certainly not the end-all of data protection. And, believe it or not, there's even some bad backup poetry.
--Rich Friedman