I’ve been looking at the book Learning FreeNAS by Gary Sims, and trying out FreeNAS in the process. FreeNAS is now at 0.69.1, and is very stable and robust. FreeNAS is based on FreeBSD and thus is rock solid.
Writing a book about FreeNAS (or any Network Attached Storage system) is difficult for several reasons. The most obvious one is that entire books (big books!) have been written about each storage technology: Windows file-sharing (SMB/CIFS), NFS, iSCSI, FTP, backups, and more.
It is difficult to write a good book about NAS as it is not possible to cover all areas in depth – and alternately, it is not good to reduce the book to “click this button; click that button; next enter this data and click that button…” A NAS can make setting up and using a complicated server quite easy – and finding the right balance between describing all of how Samba works and just specifying which buttons to push can be a hard choice to make.
Learning FreeNAS tends slightly towards the simple end: if you discover any serious problems that require command-line knowledge, the book doesn’t really cover more than it must. In my case, I found that installing FreeNAS resulted in the lack of a default route. I had to add the default network route by hand, though the book never discusses this. This is not necessarily a deficiency, but one to be aware of.
One thing that I always look for in books is an in-depth index. These are simple to find: how many pages does the index contain? How many entries does each letter contain? How many entries can be found under U or X? This book contains 6 pages of index, compared to a similarly sized book that has 17 pages – and a smaller font size. As a reference work then, it will be harder to find items that are of interest.
Overall, this is a good book, worth getting. It could have been more in-depth, but as it stands it is still good. There is no comparable book for the only serious competitor in the open source NAS arena, OpenFiler (which is based on Linux).
The book is available from Packt Publishing in print or in a downloadable PDF.
UNIX Administratosphere 
Dave, I glad that overall you enjoyed the book. I think in general the book is aimed at those with a little less experience than yourself, but your comments are valid and I will keep them in mind if I write another book.
Thanks, Gary
Thanks very much for the kind words. I should have made it clearer: one thing every writer learns is to “know your audience.” A topic such as NAS is an interesting combination of the expert and the novice, and thus an extremely difficult topic to cover enough to satisfy both audiences.
Some books I’ve seen have what you might call in-depth technical sidebars with a notation to them that essentially said: “This is technical stuff: you can read it if you like, but you don’t need to know this stuff.” Such a sidebar could be a couple paragraphs, or in some cases, a couple of pages.