Linux Server Hacks : 100 Industrial-Strength Tips and Tools

Contents......Page 5 Contributors......Page 9 Acknowledgments......Page 10 How to Become a Hacker......Page 11 1. The world is full of fascinating problems waiting to be solved.......Page 12 4. Freedom is good.......Page 13 5. Attitude is no substitute for competence.......Page 14 Preface......Page 15 How This Book Is Organized......Page 16 How to Use This Book......Page 17 How to Contact Us......Page 18 Gotta Hack?......Page 19 Server Basics......Page 21 Removing Unnecessary Services......Page 23 Forgoing the Console Login......Page 26 Common Boot Parameters......Page 27 Creating a Persistent Daemon with init......Page 29 n>&m: Swap Standard Output and StandardError......Page 30 Building Complex Command Lines......Page 32 Working with Tricky Files in xargs......Page 35 Listing: albumize......Page 36 Immutable Files in ext2/ext3......Page 37 Speeding Up Compiles......Page 39 At Home in Your Shell Environment......Page 40 Finding and Eliminating setuid/setgid Binaries......Page 43 Make sudo Work Harder......Page 45 Listing: Makefile.mail......Page 47 Listing: Makefile.push......Page 48 Brute Forcing Your New Domain Name......Page 49 Playing Hunt the Disk Hog......Page 50 Fun with /proc......Page 51 Manipulating Processes Symbolically withprocps......Page 54 Managing System Resources per Process......Page 56 Cleaning Up after Ex-Users......Page 58 Eliminating Unnecessary Drivers from the Kernel......Page 60 Using Large Amounts of RAM......Page 62 hdparm: Fine Tune IDE Drive Parameters......Page 63 Revision Control......Page 67 Getting Started with RCS......Page 68 Checking Out a Previous Revision in RCS......Page 69 Tracking Changes with rcs2log......Page 70 Typical Uses......Page 72 Importing a New Module......Page 73 CVS: Checking Out a Module......Page 74 CVS: Updating Your Working Copy......Page 75 CVS: Using Tags......Page 76 CVS: Making Changes to a Module......Page 77 Removing Files......Page 78 CVS: Branching Development......Page 79 Remote Repositories......Page 80 Developer Machines......Page 81 Installing pserver......Page 82 Using a Remote pserver......Page 83 Backups......Page 84 Backing Up with tar over ssh......Page 85 Using rsync over ssh......Page 86 Creating Archives......Page 87 Expanding Archives......Page 88 Interactive Restores......Page 89 Recursively Copy a Directory......Page 90 Incremental Backups......Page 91 Backing Up Your Boot Sector......Page 92 Keeping Parts of Filesystems in sync with rsync......Page 94 Listing: Balance-push.sh......Page 97 Automated Snapshot-Style Incremental Backups with rsync......Page 99 Extensions: Hourly, Daily, and Weekly Snapshots......Page 100 Listing: make_snapshot.sh......Page 101 Listing: Daily_snapshot_rotate.sh......Page 103 Working with ISOs and CDR/CDRWs......Page 104 Burning a CD Without Creating an ISO File......Page 106 Creating a Firewall from the Command Line of any Server......Page 108 Simple IP Masquerading......Page 111 iptables Tips & Tricks......Page 112 Advanced iptables Features......Page 113 Forwarding TCP Ports to Arbitrary Machines......Page 114 See also:......Page 115 Using Custom Chains in iptables......Page 116 Tunneling: IPIP Encapsulation......Page 117 Tunneling: GRE Encapsulation......Page 119 Using vtun over ssh to Circumvent NAT......Page 121 Automatic vtund.conf Generator......Page 126 Listing: vtundconf......Page 127 Steering syslog......Page 131 Remote Logging......Page 133 Watching Jobs with watch......Page 134 What’s Holding That Port Open?......Page 135 Checking On Open Files and Sockets with lsof......Page 136 Monitor System Resources with top......Page 139 Listing: tl......Page 140 Network Monitoring with ngrep......Page 141 Listing: go-ogle......Page 142 Scanning Your Own Machines with nmap......Page 143 Listing: diskage......Page 145 Cheap IP Takeover......Page 147 Listing: takeover......Page 148 Running ntop for Real-Time Network Stats......Page 149 See also:......Page 151 Monitoring Web Traffic in Real Time with httptop......Page 152 Listing: httptop......Page 153 Quick Logins with ssh Client Keys......Page 159 Security Concerns......Page 160 Turbo-mode ssh Logins......Page 161 Using ssh-Agent Effectively......Page 162 See Also:......Page 164 X over ssh......Page 165 Forwarding Ports over ssh......Page 166 See also:......Page 168 Get Settled in Quickly with movein.sh......Page 169 Listing: movein.sh......Page 170 Global Search and Replace with Perl......Page 171 Mincing Your Data into Arbitrary Chunks (in bash)......Page 173 Listing: mince......Page 174 Colorized Log Analysis in Your Terminal......Page 175 Information Servers......Page 177 Running BIND in a chroot Jail......Page 178 Basic Syntax......Page 180 Defining Zones in Views......Page 182 Views in Slave Name Servers......Page 183 Setting Up Caching DNS with Authority for Local Domains......Page 185 See also:......Page 186 Distributing Server Load with Round-Robin DNS......Page 187 Running Your Own Top-Level Domain......Page 188 Monitoring MySQL Health with mtop......Page 189 See also:......Page 191 Setting Up Replication in MySQL......Page 192 See also:......Page 194 MySQL Server Tuning......Page 195 See also:......Page 197 Using proftpd with a mysql Authentication Source......Page 198 Optimizing glibc, linuxthreads, and the Kernel for a Super MySQL Server......Page 200 Step 4: Expand the Maximum Filehandles at Boot......Page 201 Apache Toolbox......Page 202 Display the Full Filename in Indexes......Page 205 Quick Configuration Changes with IfDefine......Page 206 Simplistic Ad Referral Tracking......Page 208 Listing: referral-report.pl......Page 210 Mimicking FTP Servers with Apache......Page 211 Listing: logflume.pl......Page 213 Generating an SSL cert and Certificate Signing Request......Page 214 Creating Your Own CA......Page 216 See also:......Page 218 Distributing Your CA to Client Browsers......Page 219 See also:......Page 220 Serving multiple sites with the same DocumentRoot......Page 221 Delivering Content Based on the Query String Using mod_rewrite......Page 223 Using mod_proxy on Apache for Speed......Page 224 Distributing Load with Apache RewriteMap......Page 226 Ultrahosting: Mass Web Site Hosting with Wildcards, Proxy, and Rewrite......Page 228 Index......Page 233 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. 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. [This] 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. [This book] also helps you manage large-scale Web installations running Apache, MySQL, and other open source tools that are typically part of a Linux system. Written for users who already understand the basics, [the book] is built upon the expertise of people who really know what they're doing.-Back cover