David N. Blank-Edelman - Automating System Administration with Perl: Tools to Make You More Efficient

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A tremendous amount of work went into updating this book so it could be even better than the first edition. Heres some of what has been improved in the second edition:

Each chapter in this book addresses a different system administration domain and ends with a list of the Perl modules used in that chapter and references to facilitate deeper exploration of the information presented. The chapters are as follows:

This introductory chapter describes the material covered in the book in more detail, explaining how it will serve you and what you need to get the most from it. The material in this book is powerful and is meant to be used by powerful people (e.g., Unix superusers and Windows-based operating system administrators). The introduction provides some important guidelines to help you write more secure Perl programs.

This chapter is about keeping multiplatform filesystems tidy and ensuring that they are used properly. Well start by looking at the salient differences between the native filesystems for each operating system. Well then explore the process of intelligently walking or traversing filesystems from Perl and how that can be useful. Finally, well look at manipulating disk quotas from Perl.

This chapter discusses how user accounts manifest themselves on two different operating systems, including what is stored for each user and how to manipulate the information from Perl. That leads into a discussion of a rudimentary account system written in Perl. In the process of building this system, well examine the mechanisms necessary for recording accounts in a simple database, creating these accounts, and deleting them.

explores ways to automate tasks centered around user activity, introducing a number of ways to track and control process, file, and network operations initiated by users. This chapter also presents various operating system- specific frameworks and tools (e.g., Windows Management Instrumentation, GUI setup tools, lsof , etc.) that are helpful for user-oriented tasks on different platforms.

Name and configuration services allow hosts on a TCP/IP network to communicate with each other amicably and to self-configure. This chapter takes a historical perspective by starting with host files, then moving on to the Network Information Service (NIS) and finally to the glue of the Internet, the Domain Name Service (DNS). Each step of the way, it shows how Perl can make professional management of these services easier. Well also explore how to work with the Dynamic Host Configuration Protocol (DHCP) from Perl in this chapter.

Almost every system or software package we touch relies heavily on configuration files to be useful in our environment. This chapter explores the tools that make writing and reading those files from Perl easy. Well look at various formats, with special attention paid to XML and the current best practices for working with it using Perl.

Over time, more uses for relational databases are being found in the system administration realm. As a result, system administrators need to become familiar with SQL database administration. This chapter explains DBI, the preeminent SQL database framework for Perl, and provides examples of it in action for database administration .