This book focuses on automating the tedious daily tasks of system administration. It provides real-world examples and explores the tools useful for managing 2 or 5,000 systems.

This book provides a unique balance of "big picture" principles that transcend specific software packages and version numbers, and very clear procedures on securing some of those software packages. An all-inclusive resource for Linux users who wish to harden their systems, the book covers general security as well as key services such as DNS, the Apache Web server, mail, file transfer, and secure shell.

The report gives a complete defining description of the international algorithmic language Algol 60. This is a language suitable for expressing a large class of numerical processes in a form sufficiently concise for direct automatic translation into the language of programmed automatic computers. The introduction contains an account of the preparatory work leading up to the final conference, where the language was defined. In addition the notions reference language, publication language, and hardware representations are explained. In the first chapter a survey of the basic constituents and features of the language is given, and the formal notation, by which the syntactic structure is defined, is explained. The second chapter lists all the basic symbols, and the syntactic units known as identifiers, numbers, and strings are defined. Further some important notions such as quantity and value are defined. The third chapter explains the rules for forming expressions and the meaning of these expressions. Three different types of expressions exist: arithmetic, Boolean (logical), and designational. The fourth chapter describes the operational units of the language, known as statements. The basic statements are: assignment statements (evaluation of a formula), go to statements (explicit break of the sequence of execution of statements), dummy statements, and procedure statements (call for execution of a closed process, defined by a procedure declaration). The formation of more complex structures, having statement character, is explained. These include: conditional statements, for statements, compound statements, and blocks. In the fifth chapter the units known as declarations, serving for defining permanent properties of the units entering into a process described in the language, are defined. The report ends with two detailed examples of the use of the language and an alphabetic index of definitions.

Whether you need a network of ten Linux PCs and a server or a datacenter with a few thousand Unix nodes, you need to know how to automate much of the installation, configuration, and standard system administration. Build your network once using cfengine, and the network build will work, without user intervention, on any hardware you prefer.Automating Linux and Unix System Administration, Second Editionis unique in its focus on how to make the system administrator's job easier and more efficient: instead of just managing the system administrator's time, the book explains the technology to automate repetitive tasks and the methodology to automate successfully. Both new and seasoned professionals will profit from industry–leading insights into the automation process. System administrators will attain a thorough grasp of cfengine, kickstart, and shell scripting for automation. After reading all chapters and following all exercises in this book, the reader will be able to set up anything from a Linux datacenter to a small office network. What you'll learn See how to make changes on many UNIX and Linux hosts at once in a reliable and repeatable manner. Learn how to automate things correctly so you only have to do it once, by leveraging the authors' experience in setting up small, medium, and large networks. Set up a Linux datacenter or a network correctly. Explore handling real–world environments where not all hosts are configured alike via a case study of a fictional new datacenter buildout. Examine real–world examples for core infrastructure services (DNS, mail, monitoring, log analysis, security, cfengine, imaging) to build on in your environment. Understand core system administration best practices, which are a key part of how cfengine and automations deployments are outlined in the book. Learn how to make changes reversible, repeatable, and correct the first time through interaction with product/application stakeholders (programmers, product managers, customers, etc.). Who this book is for This book is for Linux system administrators who want to learn about the software and methodology to automate repetitive tasks-regardless of network or datacenter size-in one place. System managers will also find it much easier to think about network technology and automation projects if they read this book. This book is also for anyone who is interested in repeatable and secure infrastructure.

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If we let the human realities that accompanied those older tools fall into oblivion, if the arrival and actual or potential disappearance of e-mail, laptops, and so on become just a set of distant facts, then we lose a part of our humanity, a historical sense of our recent selves. We have witnessed stunning transformations of society, politics, communication, and even selfhood. New identities have emerged or been fabulously empowered—the angry citizen with a video camera handy, the hyper–social networking teenager, the blog “troll,” avatars. To understand them, to judge them well, we need steady and penetrating reminders of the changes they have wrought. The writers included here provide just that.