Linux Server Hacks, Volume Two: Tips & Tools for Connecting, Monitoring, and Troubleshooting

by William Hagen, Brian Jones

Overview

Today's system administrators deal with a vast number of situations, operating systems, software packages, and problems. Those who are in the know have kept their copy of Linux Server Hacks close at hand to ease their burden. And while this helps, it's not enough: any sys admin knows there are many more hacks, cool tips, and ways of solving problems than can fit in a single volume (one that mere mortals can lift, that is).

Which is why we created Linux Server Hacks, Volume Two, a second collection of incredibly useful tips and tricks for finding and using dozens of open source tools you can apply to solve your sys admin problems. The power and flexibility of Linux and Open Source means that there is an astounding amount of great software out there waiting to be applied to your sys admin problems — if only you knew about it and had enough information to get started. Hence, Linux Server Hacks, Volume Two.

This handy reference offers 100 completely new server management tips and techniques designed to improve your productivity and sharpen your administrative skills. Each hack represents a clever way to accomplish a specific task, saving you countless hours of searching for the right answer. No more sifting through man pages, HOWTO websites, or source code comments — the only resource you need is right here. And you don't have to be a system administrator with hundreds of boxen to get something useful from this book as many of the hacks apply equally well to a single system or a home network.

Compiled by experts, these hacks not only give you the step-by-step instructions necessary to implement the software, but they also provide the context to truly enable you to learn the technology. Topics include:

• Authentication
• Remote GUI connectivity
• Storage management
• File sharing and synchronizing resources
• Security/lockdown instruction
• Log files and monitoring
• Troubleshooting
• System rescue, recovery, and repair

Whether they help you recover lost data, collect information from distributed clients, or synchronize administrative environments, the solutions found in Linux Server Hacks, Volume Two will simplify your life as a system administrator.

Product Details

ISBN-13:	9780596100827
Publisher:	O'Reilly Media, Incorporated
Publication date:	12/01/2005
Series:	Hacks
Pages:	478
Product dimensions:	6.00(w) x 9.00(h) x 1.03(d)

About the Author

Bill von Hagen is a seasoned Linux/Unix systems administrator and computer collector. He writes articles and product reviews for Linux Planet, Linux Today, Linux Format, and Linux Magazine. He is the author of several technology books including "Hacking the TiVo, Second Edition" (Muska and Lipman), "The Definitive Guide to GCC" (Apress), and co-author of "SUSE Linux 9 Bible" (Wiley). In a past life, he was the drummer for a hardcore punk rock band, The Cynics.

Brian K. Jones is a system administrator in the department of computer science at Princeton University.

Table of Contents

	Credits	ix
	Preface	xiii
Chapter 1	Linux Authentication	1
1	Disable User Accounts Instantly	2
2	Edit Your Password File for Greater Access Control	5
3	Deny All Access in One Second or Less	7
4	Customize Authentication with PAMs	8
5	Authenticate Linux Users with a Windows Domain Controller	16
6	Centralize Logins with LDAP	21
7	Secure Your System with Kerberos	29
8	Authenticate NFS-Lovers with NIS	36
9	Sync LDAP Data with NIS	41
Chapter 2	Remote GUI Connectivity	45
10	Access Systems Remotely with VNC	46
11	Access VNC Servers over the Web	54
12	Secure VNC via SSH	56
13	Autostart VNC Servers on Demand	60
14	Put Your Desktops on a Thin Client Diet	69
15	Run Windows over the Network	78
16	Secure, Lightweight X Connections with FreeNX	82
17	Secure VNC Connections with FreeNX	89
18	Secure Windows Terminal Connections with FreeNX	91
19	Remote Administration with Webmin	93
Chapter 3	System Services	97
20	Quick and Easy DHCP Setup	98
21	Integrate DHCP and DNS with Dynamic DNS Updates	102
22	Synchronize Your Watches!	108
23	Centralize X Window System Font Resources	111
24	Create a CUPS Print Server	119
25	Configure Linux Connections to Remote CUPS Printers	128
26	Integrate Windows Printing with CUPS	130
27	Centralize Macintosh Printing with CUPS	134
28	Define a Secure CUPS Printer	138
Chapter 4	Cool Sysadmin Tools and Tips	143
29	Execute Commands Simultaneously on Multiple Servers	144
30	Collaborate Safely with a Secured Wiki	145
31	Edit Your GRUB Configuration with grubby	149
32	Give Your Tab Key a Workout	150
33	Keep Processes Running After a Shell Exits	153
34	Disconnect Your Console Without Ending Your Session	155
35	Use script to Save Yourself Time and Train Others	157
36	Install Linux Simply by Booting	159
37	Turn Your Laptop into a Makeshift Console	164
38	Usable Documentation for the Inherently Lazy	167
39	Exploit the Power of Vim	170
40	Move Your PHP Web Scripting Skills to the Command Line	173
41	Enable Quick telnet/SSH Connections from the Desktop	176
42	Speed Up Compiles	178
43	Avoid Common Junior Mistakes	181
44	Get Linux Past the Gatekeeper	184
45	Prioritize Your Work	187
Chapter 5	Storage Management and Backups	193
46	Create Flexible Storage with LVM	194
47	Combine LVM and Software RAID	203
48	Create a Copy-on-Write Snapshot of an LVM Volume	210
49	Clone Systems Quickly and Easily	214
50	Make Disk-to-Disk Backups for Large Drives	221
51	Free Up Disk Space Now	228
52	Share Files Using Linux Groups	229
53	Refine Permissions with ACLs	233
54	Make Files Easier to Find with Extended Attributes	240
55	Prevent Disk Hogs with Quotas	246
Chapter 6	Standardizing, Sharing, and Synchronizing Resources	251
56	Centralize Resources Using NFS	251
57	Automount NFS Home Directories with autofs	257
58	Keep Filesystems Handy, but Out of Your Way	260
59	Synchronize root Environments with rsync	263
60	Share Files Across Platforms Using Samba	264
61	Quick and Dirty NAS	269
62	Share Files and Directories over the Web	276
Chapter 7	Security	280
63	Increase Security by Disabling Unnecessary Services	281
64	Allow or Deny Access by IP Address	283
65	Detect Network Intruders with snort	286
66	Tame Tripwire	293
67	Verify Fileystem Integrity with Afick	299
68	Check for Rootkits and Other Attacks	303
Chapter 8	Troubleshooting and Performance	311
69	Find Resource Hogs with Standard Commands	311
70	Reduce Restart Times with Journaling Filesystems	316
71	Grok and Optimize Your System with sysctl	321
72	Get the Big Picture with Multiple Displays	323
73	Maximize Resources with a Minimalist Window Manager	327
74	Profile Your Systems Using /proc	332
75	Kill Processes the Right Way	337
76	Use a Serial Console for Centralized Access to Your Systems	339
77	Clean Up NIS After Users Depart	343
Chapter 9	Logfiles and Monitoring	346
78	Avoid Catastrophic Disk Failure	346
79	Monitor Network Traffic with MRTG	351
80	Keep a Constant Watch on Hosts	354
81	Remotely Monitor and Configure a Variety of Networked Equipment	357
82	Force Standalone Apps to Use syslog	362
83	Monitor Your Logfiles	364
84	Send Log Messages to Your Jabber Client	368
85	Monitor Service Availability with Zabbix	371
86	Fine-Tune the syslog Daemon	375
87	Centralize System Logs Securely	379
88	Keep Tabs on Systems and Services	382
Chapter 10	System Rescue, Recovery, and Repair	388
89	Resolve Common Boot and Startup Problems	389
90	Rescue Me!	396
91	Bypass the Standard Init Sequence for Quick Repairs	398
92	Find Out Why You Can't Unmount a Partition	400
93	Recover Lost Partitions	404
94	Recover Data from Crashed Disks	407
95	Repair and Recover ReiserFS Filesystems	415
96	Piece Together Data from the lost+found	422
97	Recover Deleted Files	430
98	Permanently Delete Files	433
99	Permanently Erase Hard Disks	435
100	Recover Lost Files and Perform Forensic Analysis	438
	Index	447

Editorial Reviews

The Barnes & Noble Review
O'Reilly's original Linux Server Hacks gave sysadmins 100 indispensable timesavers, tips, and solutions. This new Volume 2 offers 100 more: all of them elegant, fun, well tested, and extremely useful.

To begin, there's a full chapter on authentication in heterogeneous environments, a favorite topic of coauthor Bill von Hagen. You'll also find up-to-date collections of tips on remote connectivity, system services, storage management, security, troubleshooting, performance optimization, monitoring, system rescue, and more.

A few of our favorites: recognizing emerging problems in logfiles; booting crippled systems for diagnosis; cutting down on restore requests; using script to train junior admins; integrating Windows printing with CUPS; synchronizing multiple servers' root environments; using journaling to accelerate restarts; using your laptop as a makeshift console. That's just a taste. Your favorites may vary, but rest assured, you'll find plenty of them. Bill Camarda, from the November 2006 Read Only