UNIX and Linux System Administration Handbook, 4th Edition

TABLE OF CONTENTS......Page 6
FOREWORD......Page 43
PREFACE......Page 45
ACKNOWLEDGMENTS......Page 47
SECTION ONE: BASIC ADMINISTRATION......Page 50
CHAPTER 1 WHERE TO START......Page 52
Essential duties of the system administrator......Page 53
Suggested background......Page 55
Friction between UNIX and Linux......Page 56
Linux distributions......Page 58
Example systems used in this book......Page 59
Notation and typographical conventions......Page 62
Units......Page 63
Man pages and other on-line documentation......Page 65
Other authoritative documentation......Page 67
Other sources of information......Page 69
Ways to find and install software......Page 70
System administration under duress......Page 75
Recommended reading......Page 76
Exercises......Page 77
CHAPTER 2 SCRIPTING AND THE SHELL......Page 78
Shell basics......Page 79
bash scripting......Page 86
Regular expressions......Page 97
Perl programming......Page 103
Python scripting......Page 115
Scripting best practices......Page 122
Recommended reading......Page 123
Exercises......Page 125
CHAPTER 3 BOOTING AND SHUTTING DOWN......Page 126
Bootstrapping......Page 127
Booting PCs......Page 131
GRUB: The GRand Unified Boot loader......Page 132
Booting to single-user mode......Page 135
Working with startup scripts......Page 136
Booting Solaris......Page 146
Rebooting and shutting down......Page 149
Exercises......Page 151
CHAPTER 4 ACCESS CONTROL AND ROOTLY POWERS......Page 152
Traditional UNIX access control......Page 153
Modern access control......Page 155
Real-world access control......Page 159
Pseudo-users other than root......Page 167
Exercises......Page 168
Components of a process......Page 169
The life cycle of a process......Page 172
Signals......Page 173
kill: send signals......Page 176
Process states......Page 177
nice and renice: influence scheduling priority......Page 178
ps: monitor processes......Page 179
Dynamic monitoring with top, prstat, and topas......Page 182
The /proc filesystem......Page 184
strace, truss, and tusc: trace signals and system calls......Page 185
Runaway processes......Page 187
Exercises......Page 188
CHAPTER 6 THE FILESYSTEM......Page 189
Pathnames......Page 191
Filesystem mounting and unmounting......Page 192
The organization of the file tree......Page 194
File types......Page 196
File attributes......Page 201
Access control lists......Page 208
Exercises......Page 222
CHAPTER 7 ADDING NEW USERS......Page 223
The /etc/passwd file......Page 225
The /etc/shadow and /etc/security/passwd files......Page 232
The /etc/group file......Page 235
Adding users: the basic steps......Page 236
Adding users with useradd......Page 240
Adding users in bulk with newusers (Linux)......Page 246
Removing users......Page 247
Disabling logins......Page 249
Centralizing account management......Page 250
Recommended reading......Page 253
Exercises......Page 254
CHAPTER 8 STORAGE......Page 255
I just want to add a disk!......Page 256
Storage hardware......Page 258
Storage hardware interfaces......Page 262
Peeling the onion: the software side of storage......Page 269
Attachment and low-level management of drives......Page 272
Disk partitioning......Page 280
RAID: redundant arrays of inexpensive disks......Page 286
Logical volume management......Page 295
Filesystems......Page 303
ZFS: all your storage problems solved......Page 313
Storage area networking......Page 323
Exercises......Page 330
cron: schedule commands......Page 332
The format of crontab files......Page 333
Crontab management......Page 335
Linux and Vixie-cron extensions......Page 336
Some common uses for cron......Page 337
Exercises......Page 340
CHAPTER 10 BACKUPS......Page 341
Motherhood and apple pie......Page 342
Backup devices and media......Page 348
Saving space and time with incremental backups......Page 354
Setting up a backup regime with dump......Page 356
Dumping and restoring for upgrades......Page 363
Using other archiving programs......Page 364
Using multiple files on a single tape......Page 366
Bacula......Page 367
Commercial backup products......Page 384
Exercises......Page 386
CHAPTER 11 SYSLOG AND LOG FILES......Page 389
Finding log files......Page 390
Syslog: the system event logger......Page 393
AIX logging and error handling......Page 402
logrotate: manage log files......Page 405
Condensing log files to useful information......Page 407
Logging policies......Page 408
Exercises......Page 410
CHAPTER 12 SOFTWARE INSTALLATION AND MANAGEMENT......Page 411
Installing Linux and OpenSolaris......Page 412
Installing Solaris......Page 419
Installing HP-UX......Page 426
Installing AIX with the Network Installation Manager......Page 429
Managing packages......Page 430
Managing Linux packages......Page 431
Using high-level Linux package management systems......Page 433
Managing packages for UNIX......Page 442
Revision control......Page 446
Software localization and configuration......Page 453
Using configuration management tools......Page 457
Sharing software over NFS......Page 460
Recommended reading......Page 462
Exercises......Page 463
CHAPTER 13 DRIVERS AND THE KERNEL......Page 464
Kernel adaptation......Page 465
Drivers and device files......Page 466
Linux kernel configuration......Page 470
Solaris kernel configuration......Page 476
HP-UX kernel configuration......Page 480
Management of the AIX kernel......Page 481
Loadable kernel modules......Page 483
Linux udev for fun and profit......Page 486
Recommended reading......Page 492
Exercises......Page 493
SECTION TWO: NETWORKING......Page 494
TCP/IP and its relationship to the Internet......Page 496
Networking road map......Page 499
Packet addressing......Page 503
IP addresses: the gory details......Page 506
Routing......Page 514
ARP: the Address Resolution Protocol......Page 517
DHCP: the Dynamic Host Configuration Protocol......Page 518
Security issues......Page 521
Basic network configuration......Page 525
Linux networking......Page 533
Solaris networking......Page 543
HP-UX networking......Page 550
AIX networking......Page 555
Recommended reading......Page 557
Exercises......Page 558
CHAPTER 15 ROUTING......Page 560
Packet forwarding: a closer look......Page 561
Routing daemons and routing protocols......Page 564
Protocols on parade......Page 567
Routing strategy selection criteria......Page 570
Routing daemons......Page 571
Cisco routers......Page 574
Recommended reading......Page 577
Exercises......Page 579
CHAPTER 16 NETWORK HARDWARE......Page 580
Ethernet: the Swiss Army knife of networking......Page 581
Wireless: ethernet for nomads......Page 590
DSL and cable modems: the last mile......Page 592
Network testing and debugging......Page 593
Building wiring......Page 594
Network design issues......Page 596
Management issues......Page 598
Recommended reading......Page 599
Exercises......Page 600
CHAPTER 17 DNS: THE DOMAIN NAME SYSTEM......Page 601
Who needs DNS?......Page 603
How DNS works......Page 604
DNS for the impatient......Page 607
Name servers......Page 612
The DNS namespace......Page 615
Designing your DNS environment......Page 617
What’s new in DNS......Page 621
The DNS database......Page 623
The BIND software......Page 646
BIND configuration examples......Page 667
The NSD/Unbound software......Page 674
Updating zone files......Page 687
Security issues......Page 691
Testing and debugging......Page 716
Vendor specifics......Page 730
Recommended reading......Page 735
Exercises......Page 737
Introduction to network file services......Page 739
The NFS approach......Page 741
Server-side NFS......Page 747
Client-side NFS......Page 755
Identity mapping for NFS version 4......Page 758
nfsstat: dump NFS statistics......Page 759
Automatic mounting......Page 760
Recommended reading......Page 766
Exercises......Page 767
CHAPTER 19 SHARING SYSTEM FILES......Page 768
What to share......Page 769
Copying files around......Page 770
LDAP: the Lightweight Directory Access Protocol......Page 777
NIS: the Network Information Service......Page 785
Prioritizing sources of administrative information......Page 788
Exercises......Page 790
CHAPTER 20 ELECTRONIC MAIL......Page 791
Mail systems......Page 793
The anatomy of a mail message......Page 797
The SMTP protocol......Page 799
Mail system design......Page 802
Mail aliases......Page 805
Content scanning: spam and malware......Page 810
Email configuration......Page 823
sendmail......Page 824
sendmail configuration......Page 827
sendmail configuration primitives......Page 831
Security and sendmail......Page 844
sendmail performance......Page 851
sendmail testing and debugging......Page 854
Exim......Page 856
Postfix......Page 877
DKIM Configuration......Page 894
Integrated email solutions......Page 902
Recommended reading......Page 903
Exercises......Page 904
CHAPTER 21 NETWORK MANAGEMENT AND DEBUGGING......Page 908
Network troubleshooting......Page 909
ping: check to see if a host is alive......Page 910
SmokePing: gather ping statistics over time......Page 913
traceroute: trace IP packets......Page 914
netstat: get network statistics......Page 917
Inspection of live interface activity......Page 922
Packet sniffers......Page 923
The ICSI Netalyzr......Page 927
Network management protocols......Page 928
SNMP: the Simple Network Management Protocol......Page 929
The NET-SNMP agent......Page 932
Network management applications......Page 933
NetFlow: connection-oriented monitoring......Page 939
Recommended reading......Page 942
Exercises......Page 943
CHAPTER 22 SECURITY......Page 945
Is UNIX secure?......Page 946
How security is compromised......Page 947
Security tips and philosophy......Page 950
Passwords and user accounts......Page 955
PAM: cooking spray or authentication wonder?......Page 957
Setuid programs......Page 961
Effective use of chroot......Page 962
Security power tools......Page 963
Mandatory Access Control (MAC)......Page 971
Cryptographic security tools......Page 973
Firewalls......Page 981
Linux firewall features......Page 984
IPFilter for UNIX systems......Page 988
Virtual private networks (VPNs)......Page 991
Certifications and standards......Page 993
Sources of security information......Page 996
What to do when your site has been attacked......Page 999
Recommended reading......Page 1001
Exercises......Page 1003
CHAPTER 23 WEB HOSTING......Page 1005
Web hosting basics......Page 1006
HTTP server installation......Page 1012
Virtual interfaces......Page 1016
The Secure Sockets Layer (SSL)......Page 1020
Caching and proxy servers......Page 1023
Scaling beyond your limits......Page 1026
Exercises......Page 1028
SECTION THREE: BUNCH O\' STUFF......Page 1030
CHAPTER 24 VIRTUALIZATION......Page 1032
Virtual vernacular......Page 1033
Benefits of virtualization......Page 1037
A practical approach......Page 1038
Virtualization with Linux......Page 1040
Solaris zones and containers......Page 1046
AIX workload partitions......Page 1050
Integrity Virtual Machines in HP-UX......Page 1052
Amazon Web Services......Page 1054
Exercises......Page 1059
CHAPTER 25 THE X WINDOW SYSTEM......Page 1060
The display manager......Page 1062
Process for running an X application......Page 1063
X server configuration......Page 1068
X server troubleshooting and debugging......Page 1075
A brief note on desktop environments......Page 1077
Recommended reading......Page 1079
Exercises......Page 1080
CHAPTER 26 PRINTING......Page 1081
Printing-system architecture......Page 1082
CUPS printing......Page 1083
Printing from desktop environments......Page 1092
System V printing......Page 1094
BSD and AIX printing......Page 1103
What a long, strange trip it’s......Page 1114
Common printing software......Page 1116
Printer languages......Page 1117
PPD files......Page 1121
Paper sizes......Page 1122
Printer practicalities......Page 1124
Troubleshooting tips......Page 1130
Recommended reading......Page 1132
Exercises......Page 1133
CHAPTER 27 DATA CENTER BASICS......Page 1134
Data center reliability tiers......Page 1135
Cooling......Page 1136
Power......Page 1140
Racks......Page 1143
Recommended reading......Page 1144
Exercises......Page 1145
CHAPTER 28 GREEN IT......Page 1146
Green IT initiation......Page 1147
The green IT eco-pyramid......Page 1148
Green IT strategies: data center......Page 1149
Green IT strategies: user workspace......Page 1157
Green IT friends......Page 1159
Exercises......Page 1160
CHAPTER 29 PERFORMANCE ANALYSIS......Page 1161
What you can do to improve performance......Page 1163
Factors that affect performance......Page 1164
How to analyze performance problems......Page 1166
System performance checkup......Page 1167
Help! My system just got really slow!......Page 1180
Recommended reading......Page 1182
Exercises......Page 1183
Logging in to a UNIX system from Windows......Page 1184
Accessing remote desktops......Page 1185
Running Windows and Windows-like applications......Page 1188
Using command-line tools with Windows......Page 1189
Windows compliance with email and web standards......Page 1190
Sharing files with Samba and CIFS......Page 1191
Sharing printers with Samba......Page 1198
Debugging Samba......Page 1201
Active Directory authentication......Page 1203
Recommended reading......Page 1209
Exercises......Page 1210
CHAPTER 31 SERIAL DEVICES AND TERMINALS......Page 1211
The RS-232C standard......Page 1212
Alternative connectors......Page 1214
Hard and soft carrier......Page 1216
Serial device files......Page 1217
setserial: set serial port parameters under Linux......Page 1218
Pseudo-terminals......Page 1219
Configuration of terminals......Page 1220
Special characters and the terminal driver......Page 1226
tset: set options automatically......Page 1227
Terminal unwedging......Page 1228
Connecting to serial device consoles......Page 1229
Exercises......Page 1231
CHAPTER 32 MANAGEMENT, POLICY, AND POLITICS......Page 1232
The purpose of IT......Page 1233
The structure of an IT organization......Page 1239
The help desk......Page 1245
The enterprise architects......Page 1246
The operations group......Page 1248
Management......Page 1255
Policies and procedures......Page 1264
Disaster recovery......Page 1266
Compliance: regulations and standards......Page 1271
Legal issues......Page 1275
Organizations, conferences, and other resources......Page 1278
Exercises......Page 1280
A......Page 1282
B......Page 1283
C......Page 1285
D......Page 1286
E......Page 1288
F......Page 1290
H......Page 1291
I......Page 1292
J......Page 1293
L......Page 1294
M......Page 1296
N......Page 1297
P......Page 1299
R......Page 1302
S......Page 1303
U......Page 1309
V......Page 1310
W......Page 1311
Z......Page 1312
A BRIEF HISTORY OF SYSTEM ADMINISTRATION......Page 1313
IN DEFENSE OF AIX......Page 1323
COLOPHON......Page 1326
ABOUT THE CONTRIBUTORS......Page 1327
ABOUT THE AUTHORS......Page 1328