Linux Server Hacks: 100 Industrial-Strength Tips and Tools

by Rob Flickenger

Overview

A competent system administrator knows that a Linux server is a high performance system for routing large amounts of information through a network connection. Setting up and maintaining a Linux server requires understanding not only the hardware, but the ins and outs of the Linux operating system along with its supporting cast of utilities as well as layers of applications software. There's basic documentation online but there's a lot beyond the basics you have to know, and this only comes from people with hands-on, real-world experience. This kind of "know how" is what we sought to capture in Linux Server Hacks.Linux Server Hacks is a collection of 100 industrial-strength hacks, providing tips and tools that solve practical problems for Linux system administrators. Every hack can be read in just a few minutes but will save hours of searching for the right answer. Some of the hacks are subtle, many of them are non-obvious, and all of them demonstrate the power and flexibility of a Linux system. You'll find hacks devoted to tuning the Linux kernel to make your system run more efficiently, as well as using CVS or RCS to track the revision to system files. You'll learn alternative ways to do backups, how to use system monitoring tools to track system performance and a variety of secure networking solutions. Linux Server Hacks also helps you manage large-scale Web installations running Apache, MySQL, and other open source tools that are typically part of a Linux system.O'Reilly's new Hacks Series proudly reclaims the term "hacking" for the good guys. Hackers use their ingenuity to solve interesting problems. Rob Flickenger is an experienced system administrator, having managed the systems for O'Reilly Network for several years. (He's also into community wireless networking and he's written a book on that subject for O'Reilly.) Rob has also collected the best ideas and tools from a number of other highly skilled contributors.Written for users who already understand the basics, Linux Server Hacks is built upon the expertise of people who really know what they're doing.

Product Details

ISBN-13:	9781449378929
Publisher:	O'Reilly Media, Incorporated
Publication date:	01/20/2003
Sold by:	Barnes & Noble
Format:	eBook
Pages:	242
File size:	2 MB

About the Author

Rob Flickenger has been a professional systems administrator for more than 10 years, and all around hacker for as long as he can remember. Rob enjoys spreading the good word of open networks, open standards, and ubiquitous wireless networking. His current professional project is Metrix Communication LLC, which provides wireless hardware and software that embodies the same open source principles he rants about in his books. Rob also works with the U.N. and various international organizations to bring these ideas to places where communications infrastructure is badly needed. He hopes that all of this effort is contributing toward the ultimate goal of infinite bandwidth everywhere for free. He is the author of Linux Server Hacks, Wireless Hacks, and Building Wireless Community Networks (which is in its second edition).

Table of Contents

	How to Become a Hacker	vii
	Preface	xi
	Server Basics	1
1.	Removing Unnecessary Services	3
2.	Forgoing the Console Login	6
3.	Common Boot Parameters	7
4.	Creating a Persistent Daemon with init	8
5.	n>&m: Swap Standard Output and Standard Error	10
6.	Building Complex Command Lines	12
7.	Working with Tricky Files in xargs	15
8.	Immutable Files in ext2/ext3	17
9.	Speeding Up Compiles	18
10.	At Home in Your Shell Environment	19
11.	Finding and Eliminating setuid/setgid Binaries	22
12.	Make sudo Work Harder	25
13.	Using a Makefile to Automate Admin Tasks	27
14.	Brute Forcing Your New Domain Name	29
15.	Playing Hunt the Disk Hog	29
16.	Fun with /proc	31
17.	Manipulating Processes Symbolically with procps	34
18.	Managing System Resources per Process	35
19.	Cleaning Up after Ex-Users	37
20.	Eliminating Unnecessary Drivers from the Kernel	39
21.	Using Large Amounts of RAM	42
22.	hdparm: Fine Tune IDE Drive Parameters	43
	Revision Control	46
23.	Getting Started with RCS	47
24.	Checking Out a Previous Revision in RCS	48
25.	Tracking Changes with rcs2log	49
26.	Getting Started with CVS	51
27.	CVS: Checking Out a Module	54
28.	CVS: Updating Your Working Copy	54
29.	CVS: Using Tags	55
30.	CVS: Making Changes to a Module	56
31.	CVS: Merging Files	57
32.	CVS: Adding and Removing Files and Directories	57
33.	CVS: Branching Development	58
34.	CVS: Watching and Locking Files	59
35.	CVS: Keeping CVS Secure	60
36.	CVS: Anonymous Repositories	61
	Backups	63
37.	Backing Up with tar over ssh	64
38.	Using rsync over ssh	65
39.	Archiving with Pax	66
40.	Backing Up Your Boot Sector	72
41.	Keeping Parts of Filesystems in sync with rsync	73
42.	Automated Snapshot-Style Incremental Backups with rsync	78
43.	Working with ISOs and CDR/CDRWs	84
44.	Burning a CD Without Creating an ISO File	85
	Networking	87
45.	Creating a Firewall from the Command Line of any Server	87
46.	Simple IP Masquerading	90
47.	iptables Tips & Tricks	91
48.	Forwarding TCP Ports to Arbitrary Machines	93
49.	Using Custom Chains in iptables	94
50.	Tunneling: IPIP Encapsulation	96
51.	Tunneling: GRE Encapsulation	98
52.	Using vtun over ssh to Circumvent NAT	99
53.	Automatic vtund.conf Generator	105
	Monitoring	110
54.	Steering syslog	110
55.	Watching Jobs with watch	113
56.	What's Holding That Port Open?	114
57.	Checking On Open Files and Sockets with Isof	115
58.	Monitor System Resources with top	118
59.	Constant Load Average Display in the Titlebar	119
60.	Network Monitoring with ngrep	121
61.	Scanning Your Own Machines with nmap	123
62.	Disk Age Analysis	124
63.	Cheap IP Takeover	126
64.	Running ntop for Real-Time Network Stats	129
65.	Monitoring Web Traffic in Real Time with httptop	131
	SSH	139
66.	Quick Logins with ssh Client Keys	139
67.	Turbo-mode ssh Logins	141
68.	Using ssh-Agent Effectively	142
69.	Running the ssh-Agent in a GUI	144
70.	X over ssh	145
71.	Forwarding Ports over ssh	146
	Scripting	149
72.	Get Settled in Quickly with movein.sh	149
73.	Global Search and Replace with Perl	151
74.	Mincing Your Data into Arbitrary Chunks (in bash)	153
75.	Colorized Log Analysis in Your Terminal	155
	Information Servers	157
76.	Running BIND in a chroot Jail	158
77.	Views in BIND 9	160
78.	Setting Up Caching DNS with Authority for Local Domains	165
79.	Distributing Server Load with Round-Robin DNS	167
80.	Running Your Own Top-Level Domain	168
81.	Monitoring MySQL Health with mtop	169
82.	Setting Up Replication in MySQL	172
83.	Restoring a Single Table from a Large MySQL Dump	175
84.	MySQL Server Tuning	175
85.	Using proftpd with a mysql Authentication Source	178
86.	Optimizing glibc, linuxthreads, and the Kernel for a Super MySQL Server	180
87.	Apache Toolbox	182
88.	Display the Full Filename in Indexes	185
89.	Quick Configuration Changes with IfDefine	186
90.	Simplistic Ad Referral Tracking	188
91.	Mimicking FTP Servers with Apache	191
92.	Rotate and compress Apache Server Logs	193
93.	Generating an SSL cert and Certificate Signing Request	194
94.	Creating Your Own CA	196
95.	Distributing Your CA to Client Browsers	198
96.	Serving multiple sites with the same DocumentRoot	201
97.	Delivering Content Based on the Query String Using mod_rewrite	203
98.	Using mod_proxy on Apache for Speed	204
99.	Distributing Load with Apache RewriteMap	206
100.	Ultrahosting: Mass Web Site Hosting with Wildcards, Proxy, and Rewrite	208
	Index	213

Editorial Reviews

The Barnes & Noble Review
O’Reilly’s Rob Flickenger has compiled 100 of the world’s best ideas for optimizing Linux servers and system administration -- and, boy, are they ever useful.

Want to improve performance and security by removing unnecessary services and drivers? Track down people (or software) that are hogging disk space? Manage your system resources on a per-process basis? Eliminate setuid/setgid executables that make you susceptible to the ptrace attack? Accelerate compiles? Use makefiles to automate administration? Flickenger covers all that, and much more, in just the first quarter of the book.

Blessed with loads of RAM? Here are hacks that make the most of it. Running IDE drives? Here are hdparm tricks that dramatically improve throughput -- sometimes by as much as 6x to 10x.

You'll find excellent ideas for backup and archiving, copying arbitrary portions of your filesystem using ssh and tar, using rsync to back up incremental filesystem changes, applying pax to make portable archives that can be restored on other Unix systems, backing up your boot sector -- even burning CDs without creating ISO files.

Linux Server Hacks offers nifty solutions for firewalling and IP tunneling; server monitoring (local, network, and Web); CVS and revision control; and scripting. A full quarter of the book covers high-performance delivery of information services -- from BIND to DNS caching, MySQL server tuning to mass web site “ultrahosting.” Chances are, this book will save your organization thousands of dollars. It’ll certainly save you an enormous amount of time and hassle. Bill Camarda

Bill Camarda is a consultant, writer, and web/multimedia content developer. His 15 books include Special Edition Using Word 2000 and Upgrading & Fixing Networks For Dummies®, Second Edition.