Both Using and Administering Linux: Volume 2

Zero to SysAdmin: Advanced Topics
1. ed
ISBN: 978-1-4842-5455-4
Verlag: Apress
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 605 Seiten

Experience an in-depth exploration of logical volume management and the use of file managers to manipulate files and directories and the critical concept that, in Linux, everything is a file and some fun and interesting uses of the fact that everything is a file.This book builds upon the skills you learned in Volume 1 of this course and it depends upon the virtual network and virtual machine created there. More experienced Linux users can begin with this volume and download the assigned script that will set up the VM for the start of Volume 2. Instructions with the script will provide specifications for configuration of the virtual network and the virtual machine. Refer to the volume overviews in the book's introduction to select the volume of this course most appropriate for your current skill level.
You'll see how to manage and monitor running processes, discover the power of the special filesystems, monitor and tune the kernel while it is running - without a reboot. You'll then turn to regular expressions and the power that using them for pattern matching can bring to the command line, and learn to manage printers and printing from the command line and unlock the secrets of the hardware on which your Linux operating system is running. Experiment with command line programming and how to automate various administrative tasks, networking, and the many services that are required in a Linux system. Use the logs and journals to look for clues to problems and confirmation that things are working correctly, and learn to enhance the security of your Linux systems and how to perform easy local and remote backups. What You Will Learn Understand Logical Volume Management, using file managers, and special filesystemsExploit everything in a filePerform command line programming and basic automationConfigure printers and manage other hardwareManage system services with systemd, user management, security, and local and remote backups using simple and freely available tools Who This Book Is For Anyone who wants to continue to learn Linux in depth as an advanced user and system administrator at the command line while using the GUI desktop to leverage productivity. 


David Both is a Linux and Open Source advocate who resides in Raleigh, North Carolina. He has been in the IT industry for over forty years and taught OS/2 for IBM where he worked for over 20 years. While at IBM, he wrote the first training course for the original IBM PC in 1981. He has taught RHCE classes for Red Hat and has worked at MCI Worldcom, Cisco, and the State of North Carolina. He has been working with Linux and Open Source Software for 20 years. David has written articles for OS/2 Magazine, Linux Magazine, Linux Journal and OpenSource.com. His article 'Complete Kickstart,' co-authored with a colleague at Cisco, was ranked 9th in the Linux Magazine Top Ten Best System Administration Articles list for 2008. He has spoken at POSSCON and All Things Open (ATO).

Autoren/Hrsg.

Both, David

Inhaltsverzeichnis

1;Table of Contents;5
2;About the Author;18
3;About the Technical Reviewer;19
4;Acknowledgments;20
5;Introduction;21
6;Chapter 1: Logical Volume Management;32
6.1;Objectives;32
6.2;The need for logical volume management;32
6.2.1;Running out of disk space in VirtualBox;33
6.2.2;Recovery;33
6.3;LVM structure;34
6.4;Extending a logical volume;35
6.5;Extending volume groups;38
6.5.1;Create a new volume group – 1;38
6.5.2;Create a new volume group – 2;42
6.6;Tips;44
6.7;Advanced capabilities;45
6.8;Chapter summary;45
6.9;Exercises;46
7;Chapter 2: File Managers;47
7.1;Objectives;47
7.2;Introduction;47
7.2.1;Text-mode interface;48
7.2.2;Graphical interface;48
7.3;Default file manager;48
7.4;Text-mode file managers;50
7.4.1;Midnight Commander;50
7.5;Other text-mode file managers;61
7.5.1;Vifm;61
7.5.2;nnn;62
7.6;Graphical file managers;63
7.6.1;Krusader;64
7.7;Thunar;67
7.8;Dolphin;68
7.9;XFE;70
7.10;Chapter summary;71
7.11;Exercises;71
8;Chapter 3: Everything Is a File;72
8.1;Objectives;72
8.2;What is a file?;72
8.3;Device files;73
8.3.1;Device file creation;74
8.4;udev simplification;74
8.4.1;Naming rules;75
8.5;Device data flow;76
8.6;Device file classification;77
8.7;Fun with device files;79
8.8;Randomness, zero, and more;84
8.9;Back up the master boot record;87
8.10;Implications of everything is a file;94
8.11;Chapter summary;94
8.12;Exercises;95
9;Chapter 4: Managing Processes;96
9.1;Objectives;96
9.2;Processes;96
9.2.1;Process scheduling in the kernel;96
9.3;Tools;97
9.3.1;top;98
9.3.1.1;Summary section;100
9.3.1.2;Process section;101
9.4;More about load averages…;104
9.4.1;…and signals;105
9.5;CPU hogs;106
9.6;Process scheduling;108
9.6.1;Nice numbers;108
9.7;Killing processes;111
9.8;Other interactive tools;112
9.8.1;atop;112
9.8.1.1;Summary section;113
9.8.1.2;Process section;114
9.8.1.3;Configuration;115
9.8.2;htop;115
9.8.2.1;Summary section;116
9.8.2.2;Process section;117
9.8.2.3;Configuration;120
9.8.3;Glances;122
9.8.3.1;Summary section;122
9.8.3.2;Process section;123
9.8.3.3;Sidebar;124
9.8.3.4;Configuration;124
9.8.4;Other tools;125
9.9;The impact of measurement;131
9.10;Chapter summary;131
9.11;Exercises;132
10;Chapter 5: Special Filesystems;133
10.1;Objectives;133
10.2;Introduction;133
10.3;The /proc filesystem;134
10.3.1;The /sys filesystem;144
10.4;Swap space;149
10.4.1;Types of Linux swap;150
10.4.2;Thrashing;151
10.4.3;What is the right amount of swap space?;151
10.4.4;Adding more swap space on a non-LVM disk partition;154
10.4.5;Adding swap to an LVM disk environment;159
10.4.6;Other swap options with LVM;163
10.5;Chapter summary;163
10.6;Exercises;164
11;Chapter 6: Regular Expressions;165
11.1;Objectives;165
11.2;Introducing regular expressions;165
11.3;Getting started;167
11.3.1;The mailing list;167
11.3.1.1;The first solution;169
11.3.1.2;The second solution;174
11.4;grep;175
11.4.1;Data flow;175
11.4.2;regex building blocks;176
11.4.3;Repetition;179
11.4.4;Other metacharacters;180
11.5;sed;182
11.6;Other tools that implement regular expressions;184
11.7;Resources;184
11.8;Chapter summary;185
11.9;Exercises;185
12;Chapter 7: Printing;186
12.1;Objectives;186
12.2;Introduction;187
12.3;About printers;187
12.3.1;Print languages;188
12.3.2;Printers and Linux;188
12.3.3;CUPS;191
12.3.4;Creating the print queue;193
12.4;Printing to a PDF file;198
12.5;File conversion tools;201
12.5.1;a2ps;202
12.5.2;ps2pdf;204
12.5.3;pr;204
12.5.4;ps2ascii;205
12.6;Operating system–related conversion tools;207
12.6.1;unix2dos;208
12.6.2;dos2unix;210
12.6.3;unix2mac and mac2unix;210
12.7;Miscellaneous tools;211
12.7.1;lpmove;211
12.7.2;wvText and odt2txt;214
12.8;Chapter summary;216
12.9;Exercises;216
13;Chapter 8: Hardware Detection;218
13.1;Objectives;218
13.2;Introduction;218
13.3;dmidecode;220
13.4;lshw;228
13.5;lsusb;232
13.6;usb-devices;234
13.7;lspci;236
13.8;Cleanup;239
13.9;Chapter summary;240
13.10;Exercises;240
14;Chapter 9: Command-Line Programming;241
14.1;Objectives;241
14.2;Introduction;241
14.3;Definition of a program;242
14.4;Simple CLI programs;243
14.4.1;Some basic syntax;243
14.4.2;Output to the display;245
14.4.3;Something about variables;247
14.5;Control operators;249
14.5.1;Return codes;250
14.5.2;The operators;251
14.6;Program flow control;253
14.6.1;true and false;254
14.6.2;Logical operators;255
14.6.2.1;Syntax;255
14.6.2.2;File operators;256
14.6.2.3;String comparison operators;261
14.6.2.4;Numeric comparison operators;264
14.6.2.5;Miscellaneous operators;266
14.7;Grouping program statements;267
14.8;Expansions;270
14.8.1;Brace expansion;271
14.8.2;Tilde expansion;271
14.8.3;Pathname expansion;271
14.8.4;Command substitution;273
14.8.5;Arithmetic expansion;274
14.9;for loops;276
14.10;Other loops;281
14.10.1;while;281
14.10.2;until;283
14.11;Chapter summary;284
14.12;Exercises;285
15;Chapter 10: Automation with Bash Scripts;286
15.1;Objectives;286
15.2;Introduction;287
15.3;Why I use shell scripts;287
15.3.1;Shell scripts;288
15.3.2;Scripts vs. compiled programs;289
15.4;Updates;290
15.4.1;About updates;290
15.4.2;Create a list of requirements;290
15.4.3;The CLI program;292
15.4.4;Convert the CLI program to a script;292
15.4.5;Add some logic;294
15.4.6;Limit to root;296
15.4.7;Add command-line options;297
15.4.8;Check for updates;299
15.4.9;Is a reboot required?;301
15.4.10;Adding a Help function;304
15.4.11;Finishing the script;307
15.5;About testing;308
15.5.1;Testing in production;309
15.5.2;Fuzzy testing;310
15.5.3;Testing the script;310
15.6;Making it better;313
15.7;Licensing;314
15.8;Automated testing;317
15.9;Security;317
15.10;Additional levels of automation;318
15.11;Chapter summary;320
15.12;Exercises;321
16;Chapter 11: Time and Automation;322
16.1;Objectives;322
16.2;Introduction;322
16.3;Keeping time with chrony;323
16.3.1;The NTP server hierarchy;323
16.3.2;NTP choices;324
16.3.3;Chrony structure;325
16.3.4;Client configuration;325
16.3.5;chronyc as an interactive tool;329
16.4;Using cron for timely automation;330
16.4.1;The crond daemon;331
16.4.2;crontab;331
16.4.2.1;cron examples;333
16.4.2.2;crontab entries;334
16.5;Other scheduling options;337
16.5.1;/etc/cron.d;337
16.5.2;anacron;338
16.6;Thoughts about cron;340
16.6.1;Scheduling tips;340
16.6.2;Security;341
16.6.3;cron resources;341
16.7;at;342
16.7.1;Syntax;342
16.7.2;Time specifications;342
16.7.3;Security;348
16.8;Cleanup;348
16.9;Chapter summary;348
16.10;Exercises;349
17;Chapter 12: Networking;350
17.1;Objectives;350
17.2;Introduction;350
17.2.1;About IPv6;351
17.3;Basic networking concepts;351
17.3.1;Definitions;351
17.3.2;MAC address;353
17.3.3;IP address;356
17.3.3.1;IP address assignments;359
17.4;TCP/IP;359
17.4.1;The TCP/IP network model;359
17.4.2;A simple example;361
17.5;CIDR – Network notation and configuration;363
17.5.1;Network classes;363
17.5.2;Along came a CIDR;366
17.5.3;Variable Length Subnet Masking;369
17.6;DHCP client configuration;373
17.7;NIC naming conventions;374
17.7.1;How it works – sort of;374
17.8;NIC configuration files;376
17.8.1;Create an interface configuration file;377
17.9;The interface configuration file;379
17.9.1;The network file;384
17.9.2;The route- file;384
17.9.3;Other network files;385
17.10;Network startup;385
17.10.1;The NetworkManager service;385
17.11;Name services;386
17.11.1;How a name search works;387
17.11.2;Using the /etc/hosts file;388
17.12;Introduction to network routing;392
17.12.1;The routing table;392
17.13;iptraf-ng;398
17.14;Cleanup;402
17.15;Chapter summary;402
17.16;Exercises;403
18;Chapter 13: systemd;404
18.1;Objectives;404
18.2;Introduction;404
18.3;Controversy;405
18.3.1;Why I prefer SystemV;405
18.3.2;Why I prefer systemd;406
18.3.3;The real issue;407
18.4;systemd suite;407
18.4.1;Practical structure;408
18.5;systemctl;409
18.5.1;Service units;413
18.5.2;Mount units;416
18.6;systemd timers;420
18.6.1;Time specification;421
18.6.2;Timer configuration;424
18.7;systemd-analyze;428
18.8;Journals;429
18.9;Chapter summary;432
18.10;References;433
18.11;Exercises;435
19;Chapter 14: D-Bus and udev;436
19.1;Objectives;436
19.2;/dev chaos;436
19.2.1;About D-Bus;437
19.2.2;About udev;437
19.3;Naming rules;440
19.4;Making udev work;441
19.4.1;Using Udev for your success;441
19.4.1.1;A basic script;441
19.4.1.2;Unique device identification;442
19.4.1.3;Refining the rule into something useful;445
19.4.1.4;Security;446
19.4.1.5;Udev in the real world;447
19.4.1.6;Udev is your Dev;448
19.5;Chapter summary;448
19.6;Exercises;449
20;Chapter 15: Logs and Journals;450
20.1;Objectives;450
20.2;Logs are your friend;450
20.3;SAR;451
20.4;logrotate;454
20.5;messages;458
20.6;Mail logs;460
20.7;dmesg;461
20.8;secure;463
20.9;Following log files;465
20.10;systemd journals;467
20.11;logwatch;471
20.12;Chapter summary;481
20.13;Exercises;481
21;Chapter 16: Managing Users;483
21.1;Objectives;483
21.2;Introduction;483
21.3;The root account;484
21.4;Your account;484
21.4.1;Your home directory;485
21.5;User accounts and groups;485
21.5.1;The /etc/passwd file;487
21.5.2;nologin shells;491
21.5.3;The /etc/shadow file;491
21.5.4;The /etc/group file;496
21.5.5;The /etc/login.defs file;496
21.5.6;Account configuration files;496
21.6;Password security;497
21.6.1;Password encryption;498
21.6.2;Generating good passwords;500
21.6.3;Password quality;502
21.7;Managing user accounts;504
21.7.1;Creating new accounts;504
21.7.1.1;The useradd command;504
21.7.2;Creating new accounts by editing the files;507
21.7.3;Locking the password;510
21.7.4;Deleting user accounts;511
21.8;Forcing account logoff;512
21.9;Setting resource limits;513
21.10;Chapter summary;517
21.11;Exercises;517
22;Chapter 17: Security;519
22.1;Objectives;519
22.2;Introduction;519
22.2.1;Security by obscurity;521
22.2.2;What is security?;521
22.2.3;Data protection;522
22.3;Security vectors;522
22.3.1;Self-inflicted problems;523
22.3.2;Environmental problems;523
22.3.3;Physical attacks;524
22.3.4;Network attacks;525
22.3.5;Software vulnerabilities;526
22.4;Linux and security;526
22.5;Login security;527
22.6;Checking logins;528
22.7;Telnet;532
22.8;SSH;540
22.8.1;The SSH server;540
22.9;Firewalls;544
22.9.1;firewalld;545
22.9.1.1;Understanding the rules;548
22.9.1.2;Deleting and adding rules;548
22.9.2;iptables;551
22.9.2.1;Converting to IPTables;551
22.9.2.2;Understanding the rule set;553
22.9.2.3;Managing rules with IPTables;556
22.10;Fail2Ban;559
22.11;PAM;562
22.12;Some basic steps;563
22.13;Chapter summary;566
22.14;Exercises;566
23;Chapter 18: Backup Everything – Frequently;568
23.1;Introduction;568
23.2;Backups to the rescue;568
23.2.1;The problem;569
23.3;Backup options;575
23.4;tar;575
23.5;Off-site backups;580
23.6;Disaster recovery services;581
23.7;Options;582
23.8;What about the “frequently” part?;582
23.8.1;How frequent is “frequently?”;583
23.8.2;What does “full” really mean?;583
23.8.3;All vs. diff;584
23.8.4;Considerations for automation of backups;584
23.8.5;Dealing with offline hosts;585
23.8.6;Advanced backups;585
23.9;Chapter summary;586
23.10;Exercises;586
24;Bibliography;588
24.1;Books;588
24.2;Web sites;589
25;Index;593