C/C++ Users Journal February 2004
It is possible in enterprise circumstances to have your UNIX in so specific an environment that no collection of general texts is likely to provide the quick guidance you need. Linux on the Mainframe, by John Eilert, Maria Eisenhaendler, Dorothea Matthaeus, and Ingolf Salm, is a specific text for one such specific environment — Linux running under IBM z/VM, the virtual machine mainframe operating system. Multiple multiuser Linux images can be instanced on one machine under z/VM to create a server farm environment like no other. (Yes, I'm glossing over LPAR. Don't worry, the book doesn't gloss it over.) The four IBM authors of Linux on the Mainframe focus on the unique features and problems of this sort of Linuxing.
Although they review the history and structure of Linux, fortunately the authors of this book don't attempt to teach everything. They assume you know quite a bit about both UNIX and mainframes, then limit their brief to describing how the two interact. Ever wondered what percentage of code was added to the GNU tree by the IBM port of GCC and all the tools beyond and between to port Linux? Or how to provide centralized authentication for all your virtual Linux machines from a z/OS — IBM's mainframe server operating system that can run under z/VM — LDAP server? How to use virtual channel-to-channel connectors from Linux? Or how to maximize that limited CTCC resource by hooking your virtual Linux machines to a virtual LAN? The book authoritatively covers these and scores of other topics, which have caused administrators to post in anguish to the mailing lists in the four years since the 390 port hit the ground running.
Linux on the Mainframe is prettier than an IBM Redbook, it's timely, and all the authors have (or had) close involvement in the Linux/390 project. It's aimed at administrators, or perhaps more precisely, coders or team leaders who must consider administrative issues, and at their immediate decision makers. A certain percentage of this book is (surprise!) marketing noise. But the signal-to-noise ratio is high: If you need some reliable yet compact Linux-on-the-mainframe information and don't care to wade through all the documentation and Redbooks merely in pursuit of an overview and some detailed general guidance, then Linux on the Mainframe is for you.
Practical Unix & Internet Security, Third Edition, by Simson Garfinkel, Gene Spafford, and Alan Schwartz, is a classic that, like the proverbial farmer, is outstanding in its field. Now in its third edition, this book was originally written in 1991 at which time, say the authors, "...many people thought that the words 'Unix security' were an oxymoron like 'jumbo shrimp or 'Congressional action'..." Well, those halcyon days are gone for good, yet Practical Unix & Internet Security remains the one-volume complete introduction to the basic issues of UNIX security. Covering pretty much everything takes up almost 1000 pages. The rest of mastering UNIX security is practice, experience, and plenty of reading-the-manual for your particular system, as the authors never tire of reminding you.
Practical Unix & Internet Security, while profoundly technical and highly detailed, possesses nonetheless a viewpoint well above the technical horizon. There's a whole chapter on personnel security since, after all, it's neglected wetware that causes all the problems, right? And the authors of this engagingly written, but rather ponderous tome, never forget to provide the periodic rest-and-stretch in the form of sidebars that amuse you by elucidating tangentially such diverse subjects as the origin of the term "baud" and the microwave transmitter at the University of California at Berkeley, which was continually being smashed by vandals until a very low-tech solution was discovered.
If you're in charge of security for any online UNIX system or systems, go to http://www.oreilly.com/catalog/puis3/index.html and read the table of contents. You'll probably discover you could benefit from reading this uniquely useful and comprehensive volume that only improves with age.
W. Richard Stevens (1951-1999) may be gone, but his work lives on, especially his classic Unix Network Programming. After you have learned the basics of TCP/IP and desire to actually do any TCP/IP programming, such as every beginner's sample telnet client, Unix Network Programming Volume 1 is the first and only book you need turn to. (Volume 2 deals with interprocess communication and is equally valuable in its own right.)
The first two editions, prepared totally by Stevens, were subtitled "Sockets and XTI." The second edition added IPv6 information, that protocol then "under construction." Now in its third edition, the book has been updated by the supplemental authors to cover real-world IPv6, IPSEC, and SCTP. The source code has also now been tested on a variety of newer platforms, such as Red Hat Linux 9, Solaris 9, and Mac OS X. The discussion of XTI (X/Open Transport Interface) has been dropped since nearly everyone has forgotten it, if indeed they ever knew it existed in the first place.
Compendious, accurate, insightful, and authoritative to the measure of the obsessive genius of one of the Golden Age of Programming's greatest programmer-guru-authors, now diligently redacted and supplemented by studious disciples, Unix Network Programming never stops giving. You'll have this unique and irreplaceable book on your shelf until the next edition, or until TCP/IP itself ceases to have meaning.