Introduction xxv
Part 1 Basic Admin Functions 1
Chapter 1 Understanding the Basics 3
What is Linux? 3
Looking into the Linux Kernel 4
The GNU Utilities 12
Linux User Interfaces 12
Linux Distributions 18
Core Linux Distributions 19
Specialized Linux Distributions 19
The Bottom Line 20
Chapter 2 Installing an Ubuntu Server 23
Pre-Installation Requirements 23
Hardware Requirements 24
Virtual Server Requirements 25
Finding the Software 26
Oracle VirtualBox 26
Ubuntu Server 26
Running the Installation 29
Oracle VirtualBox 29
Ubuntu Server 33
Checking the Installation 49
The Bottom Line 50
Chapter 3 Installing and Maintaining Software in Ubuntu 53
Exploring Package Management 53
Inspecting the Debian-Based Systems 54
Managing Packages with apt 54
Installing Software Packages with apt 56
Upgrading Software with apt 59
Uninstalling Software with apt 60
The apt Repositories 61
Using Snap Containers 62
Installing from Source Code 64
The Bottom Line 66
Chapter 4 Installing a Red Hat Server 69
Pre-Installation Requirements 69
Hardware Requirements 70
Virtual Server Requirements 71
Finding the Software 72
Oracle VirtualBox 72
CentOS 73
Running the Installation 76
Oracle VirtualBox 77
CentOS 77
Checking the Installation 96
The Bottom Line 97
Chapter 5 Installing and Maintaining Software in Red Hat 99
Exploring Red Hat Packages 99
Automated Package Management 100
Listing Installed Packages 100
Installing Software with dnf 102
Upgrading Software with dnf 104
Uninstalling Software with dnf 104
Handling Broken Dependencies 105
Working with RPM Repositories 106
Working Directly with Packages 107
Finding Package Files 107
Inspecting Package Files 108
Installing Package Files 109
Removing Package Files 110
Using Flatpak Containers 111
The Bottom Line 113
Chapter 6 Working with the Shell 115
Exploring the Shell 115
The Shell Prompt 116
The Shell Manual 117
Working with Commands 121
Entering Commands 121
Retrieving Past Commands 123
Redirecting Commands 125
Environment Variables 129
Global Environment Variables 129
User-Defined Environment Variables 131
The Bottom Line 133
Chapter 7 Exploring Linux File Management 135
Filesystem Navigation 135
The Linux Filesystem 135
Traversing Directories 138
Linux Files 139
Determining File Types 139
Filenames 140
Hidden Files 140
File Inodes 141
File and Directory Listing 142
Basic Listing 142
Modifying Listing Information 143
The Complete Parameter List 143
Directory Handling 146
Creating Directories 146
Deleting Directories 146
File Handling 147
Creating Files 147
Copying Files 148
Linking Files 150
Renaming Files 152
Deleting Files 152
File Features 154
Using Wildcards 154
Quoting 155
Case Sensitivity 156
Finding Files 156
The which Command 156
The locate Command 156
The whereis Command 157
The find Command 157
Archiving Files 159
Compressing Files 159
Creating Archive Files 160
Archiving Scenarios 161
The Bottom Line 163
Chapter 8 Working with Text Files 165
The vim Editor 165
Checking Your vim Editor Program 166
Using the vim Editor 167
The nano Editor 170
Working with Data Files 172
Sorting 172
Searching 175
Compressing 181
Archiving 182
The Bottom Line 187
Part 2 Intermediate Admin Functions 189
Chapter 9 Managing Hardware 191
Device Driver Modules 191
Listing Installed Modules 192
Installing New Modules 193
Removing Modules 196
Communicating with Devices 196
Device Interfaces 196
The /dev Directory 198
The /proc Directory 199
The /sys Directory 202
Working with Devices 203
Finding Devices 203
Working with PCI Cards 205
Working with USB Devices 206
Using Hot Pluggable Devices 207
Detecting Dynamic Devices 208
Working with Dynamic Devices 208
The Bottom Line 209
Chapter 10 Booting Linux 211
Understanding the Boot Process 211
Overview of the Boot Process 211
Watching the Boot Process 212
The Firmware Startup 212
The GRUB2 Bootloader 214
Configuring the GRUB2 Bootloader 215
Exploring the GRUB2 Configuration 215
Interacting with GRUB2 217
The systemd Initialization Process 219
Exploring Unit Files 220
Focusing on Service Unit Files 221
Focusing on Target Unit Files 225
Changing a Unit Configuration File 226
Changing the systemd Configuration File 227
Looking at systemctl 227
Jumping Targets 230
Analyzing with systemd 232
The Bottom Line 234
Chapter 11 Working with Storage Devices 235
Storage Basics 235
Drive Connections 235
Partitioning Drives 236
Automatic Drive Detection 236
Partitioning Tools 237
Working with fdisk 237
Working with gdisk 239
The GNU parted Command 241
Formatting Filesystems 243
Common Filesystem Types 243
Creating Filesystems 245
Mounting Filesystems 246
Manually Mounting Devices 246
Automatically Mounting Devices 247
Managing Filesystems 249
Retrieving Filesystem Stats 249
Filesystem Tools 250
Storage Alternatives 251
Multipath 251
Logical Volume Manager 251
Using RAID Technology 253
The Bottom Line 254
Chapter 12 Configuring Network Settings 255
Network Settings 255
Ubuntu Servers 256
Red Hat Servers 258
Using Network Command-Line Tools 260
NetworkManager Tools 260
Other Tools 262
Basic Network Troubleshooting 269
Sending Test Packets 269
Finding Host Information 271
Advanced Network Troubleshooting 273
The netstat Command 273
Examining Sockets 276
The Bottom Line 277
Chapter 13 Managing Users and Groups 279
Understanding Linux Permissions 279
Understanding Ownership 280
Controlling Access Permissions 282
Exploring Special Permissions 284
Managing Default Permissions 285
Using Access Control Lists 288
Managing User Accounts 290
Adding Accounts 290
Maintaining Accounts 298
Removing Accounts 301
Maintaining the Environment 302
Setting Environment Variables 302
Exploring User Entries 302
Exploring Global Entries 303
Managing Groups 304
Adding Groups 305
Removing Groups 306
The Bottom Line 307
Chapter 14 Working with Processes and Jobs 309
Looking at Processes 309
Monitoring Processes in Real Time 311
Managing Processes 314
Setting Priorities 314
Stopping Processes 315
Running Programs in Background Mode 317
Running in the Background 317
Running Multiple Background Jobs 318
Running Programs Without a Console 319
Job Control 320
Viewing Jobs 320
Restarting Stopped Jobs 322
Scheduling Jobs 323
Scheduling a Job Using the at Command 323
Scheduling Recurring Programs 326
The Bottom Line 328
Chapter 15 Managing Log Files 329
The systemd Journaling System 329
Configuring systemd-journald 330
Looking at Journal Files 331
Making the Journal Persistent 332
Viewing Journal Entries 332
Maintaining the Journal 335
Viewing Different Journal Files 337
Protecting Journal Files 337
Making Journal Entries 337
The rsyslog Legacy System 338
The syslog Protocol 338
Basic Logging Using rsyslogd 340
Layering Your Logging 342
Making Log Entries 343
Finding Event Messages 344
The Bottom Line 344
Chapter 16 Managing Printers 347
The Common Unix Printing System 347
Printer Drivers 347
Web Interface 348
Command-Line Commands 348
Printer Sharing 349
Printer Classes 350
Installing and Configuring CUPS 350
Installing CUPS 351
Preparing the Server to Use CUPS 354
Using CUPS 356
Administration Functions 356
Managing Printers and Jobs in CUPS 360
The Bottom Line 361
Part 3 Advanced Admin Functions 363
Chapter 17 Exploring Ubuntu Security 365
Locking Down Root 365
Looking at Linux Account Types 366
Gaining Super User Privileges 367
Using OpenSSH on Ubuntu 369
Exploring Basic SSH Concepts 370
Configuring SSH 372
Generating SSH Keys 373
Authenticating with SSH Keys 374
The AppArmor System 376
Network Security Using Firewalls 380
Understanding UFW 380
Configuring UFW 381
The Bottom Line 385
Chapter 18 Exploring Red Hat Security 387
Working with Root Access 387
Keeping Track of Root Logins 388
Disabling Root Access from SSH 388
Enabling Automatic Logout 389
Blocking Root Access 390
Using SELinux 391
Enabling SELinux 391
Understanding Security Context 392
Using Policies 393
Network Security Using Firewalls 395
Red Hat Firewall Concepts 395
Checking the Firewall Status 397
Working with Zones 398
Working with Firewall Rules 399
The Bottom Line 401
Chapter 19 Writing Scripts 403
Beginning a Shell Script 403
Creating a Script File 403
Displaying Messages 405
Using Variables 407
Environment Variables 407
User Variables 408
Command Substitution 409
Exiting the Script with Status 410
Passing Parameters 411
Adding Conditional Expressions 414
Working with the if-then Statement 414
Using Compound Tests 417
Working with the if-then-else Statement 418
Trying the case Statement 419
Using Loops 420
Looking at the for Command 420
Working with the while Format 423
Using the until Command 424
Using Functions 427
Creating Functions 427
Calling Functions 427
The Bottom Line 430
Chapter 20 Managing Web Servers 433
Linux Web Servers 433
Apache 433
nginx 434
The Apache Web Server 435
Installing an Apache Server 435
Configuring the Apache Server 437
Hosting Dynamic Web Applications 445
Creating a Secure Web Server 447
The nginx Server 448
Installing nginx 448
Configuring nginx 449
The Bottom Line 451
Chapter 21 Managing Database Servers 453
Linux Database Servers 453
Organizing the Data 454
Querying the Data 455
Controlling the Data 456
Installing and Using MySQL/MariaDB 457
Conducting a MariaDB Installation 458
Accessing a MariaDB Database 462
Populating and Using MariaDB Database 466
Installing and Using PostgreSQL 471
Conducting a PostgreSQL Installation 471
Accessing a PostgreSQL Database 474
Populating and Using a PostgreSQL Database 477
The Bottom Line 478
Chapter 22 Exploring the Virtualization Environment 481
Hypervisors 481
Managing VMs 481
Creating a Virtual Machine 483
Integrating via Linux Extensions 485
Containers 486
Exploring Container Types 487
Looking at Container Software 487
Organizing Containers 489
Software Packaging 491
Looking at Ubuntu Snap 491
Looking at Flatpak 499
The Bottom Line 503
Appendix The Bottom Line 505
Chapter 1: Understanding the Basics 505
Chapter 2: Installing an Ubuntu Server 506
Chapter 3: Installing and Maintaining Software in Ubuntu 507
Chapter 4: Installing a Red Hat Server 509
Chapter 5: Installing and Maintaining Software in Red Hat 510
Chapter 6: Working with the Shell 512
Chapter 7: Exploring Linux File Management 513
Chapter 8: Working with Text Files 515
Chapter 9: Managing Hardware 516
Chapter 10: Booting Linux 517
Chapter 11: Working with Storage Devices 519
Chapter 12: Configuring Network Settings 520
Chapter 13: Managing Users and Groups 521
Chapter 14: Working with Processes and Jobs 523
Chapter 15: Managing Log Files 524
Chapter 16: Managing Printers 526
Chapter 17: Exploring Ubuntu Security 527
Chapter 18: Exploring Red Hat Security 528
Chapter 19: Writing Scripts 529
Chapter 20: Managing Web Servers 532
Chapter 21: Managing Database Servers 533
Chapter 22: Exploring the Virtualization Environment 535
Index 537
