Ubuntu Linux Toolbox

Introduction xix

Chapter 1: Starting with Ubuntu Linux 1

Ubuntu, Debian, and Linux 2

Understanding Ubuntu Releases 3

Ubuntu Compared to Other Linux Distributions 3

Finding Ubuntu Resources 5

Ubuntu Software 7

Focusing on Linux Commands 7

Finding Commands 9

Reference Information in Ubuntu 11

Using help Messages 12

Using man Pages 12

Using info Documents 15

Summary 15

Chapter 2: Installing Ubuntu and Adding Software 17

Obtaining and Installing Ubuntu 17

Preparing to Install 18

Choosing Installation Options 19

Answering Installation Questions 19

Working with Debian Software Packages 20

Working with Software Packages 22

Enabling More Repositories for apt 23

Adding Software Collections with tasksel 24

Managing Software with APT 25

Finding Packages with APT 27

Installing Packages with APT 27

Upgrading Packages with APT 28

Upgrading a Single Package with APT 28

Removing Packages with APT 29

Cleaning Up Packages with APT 29

Downloading Packages with APT 30

Managing Software with dpkg 30

Installing a Package with dpkg 32

Removing a Package with dpkg 32

Extracting Files from a .deb File with dpkg 32

Querying Information about .deb Packages 33

Managing Software with aptitude 35

Updating and Upgrading Packages with aptitude 37

Querying Information about Packages with aptitude 37

Installing Packages with aptitude 38

Removing Packages with aptitude 38

Cleaning Up Packages with aptitude 39

Useful Combinations of Options with aptitude 39

Verifying Installed Packages with debsums 41

Building deb Packages 44

Summary 47

Chapter 3: Using the Shell 49

Terminal Windows and Shell Access 49

Using Terminal Windows 49

Using Virtual Consoles 51

Using the Shell 52

Using Bash History 53

Using Command Line Completion 54

Redirecting stdin and stdout 54

Using alias 57

Watching Commands 58

Watching Files 58

Acquiring Super User Power 58

Delegating Power with sudo 59

Using the su Command 61

Using Environment Variables 62

Creating Simple Shell Scripts 64

Editing and Running a Script 64

Adding Content to Your Script 65

Summary 68

Chapter 4: Working with Files 69

Understanding File Types 69

Using Regular Files 69

Using Directories 71

Using Symbolic and Hard Links 71

Using Device Files 72

Using Named Pipes and Sockets 73

Setting File/Directory Permissions 73

Changing Permissions with chmod 74

Setting the umask 76

Changing Ownership 76

Traversing the Filesystem 77

Copying Files 79

Changing File Attributes 80

Searching for Files 82

Finding Files with locate 82

Locating Files with find 83

Using Other Commands to Find Files 85

Finding Out More about Files 86

Listing Files 86

Verifying Files 86

Summary 88

Chapter 5: Manipulating Text 89

Matching Text with Regular Expressions 89

Editing Text Files 90

Using the JOE Editor 91

Using the Pico and nano Editors 92

Graphical Text Editors 94

Listing, Sorting, and Changing Text 94

Listing Text Files 94

Paging through Text 95

Paginating Text Files with pr 96

Searching for Text with grep 97

Replacing Text with sed 99

Translating or Removing Characters with tr 101

Checking Differences between Two Files with diff 101

Using awk and cut to Process Columns 104

Converting Text Files to Different Formats 105

Summary 105

Chapter 6: Playing with Multimedia 107

Working with Audio 107

Playing Music 107

Adjusting Audio Levels 109

Ripping CD Music 110

Encoding Music 111

Streaming Music 114

Converting Audio Files 116

Transforming Images 117

Getting Information about Images 117

Converting Images 118

Converting Images in Batches 119

Playing with Video 121

Playing Video Files 121

Summary 123

Chapter 7: Administering Filesystems 125

Understanding Filesystem Basics 125

Creating and Managing Filesystems 127

Partitioning Hard Disks 127

Working with Filesystem Labels 131

Formatting a Filesystem 132

Viewing and Changing Filesystem Attributes 133

Creating and Using Swap Partitions 135

Mounting and Unmounting Filesystems 136

Mounting Filesystems from the fstab File 136

Mounting Filesystems with the mount Command 138

Unmounting Filesystems with umount 140

Checking Filesystems 141

Creating Encrypted Filesystems 143

Checking RAID Disks 146

Finding Out about Filesystem Use 147

Logical Volume Manager 149

Creating LVM Volumes 149

Using LVM Volumes 151

Growing the LVM Volume 152

Shrinking an LVM Volume 153

Removing LVM Logical Volumes and Groups 153

Summary 154

Chapter 8: Backups and Removable Media 155

Backing Up Data to Compressed Archives 155

Creating Backup Archives with tar 155

Using Compression Tools 157

Listing, Joining, and Adding Files to tar Archives 160

Deleting Files from tar Archives 160

Backing Up over Networks 161

Backing Up tar Archives over ssh 161

Backing Up Files with rsync 162

Backing Up with unison 164

Backing Up to Removable Media 165

Creating Backup Images with mkisofs 165

Burning Backup Images with cdrecord 168

Making and Burning DVDs with growisofs 170

Summary 170

Chapter 9: Checking and Managing Running Processes 171

Listing Active Processes 172

Viewing Active Processes with ps 172

Watching Active Processes with top 177

Finding and Controlling Processes 179

Using pgrep to Find Processes 179

Using fuser to Find Processes 180

Changing Running Processes 181

Scheduling Realtime Processes 188

Summary 189

Chapter 10: Managing the System 191

Monitoring Resources 191

Monitoring Memory Use 192

Monitoring CPU Usage 196

Monitoring Storage Devices 198

Mastering Time 201

Changing Time/Date with Graphical Tools 201

Displaying and Setting Your System Clock 202

Displaying and Setting Your Hardware Clock 203

Using Network Time Protocol to

Set Date/Time 204

Managing the Boot Process 205

Understanding the GRUB Boot Loader 205

Modifying the GRUB Boot Loader 206

Controlling Startup and Run Levels 207

Straight to the Kernel 209

Poking at the Hardware 211

Summary 213

Chapter 11: Managing Network Connections 215

Configuring Networks from the GUI 215

Managing Network Interface Cards 216

Managing Network Connections 221

Starting and Stopping Ethernet Connections 221

Viewing Ethernet Connection Information 223

Using Wireless Connections 225

Checking Name Resolution 226

Troubleshooting Network Problems 228

Checking Connectivity to a Host 228

Checking Address Resolution Protocol 229

Tracing Routes to Hosts 231

Displaying netstat Connections and Statistics 233

Other Useful Network Tools 234

Summary 235

Chapter 12: Accessing Network Resources 237

Running Commands to Browse the Web 237

Transferring Files 239

Downloading Files with wget 239

Transferring Files with cURL 241

Transferring Files with FTP Commands 241

Using SSH Tools to Transfer Files 243

Using Windows File Transfer Tools 246

Sharing Remote Directories 246

Sharing Remote Directories with NFS 246

Sharing Remote Directories with Samba 248

Sharing Remote Directories with SSHFS 251

Chatting with Friends in IRC 252

Using Text-Based Eâ'mail Clients 253

Managing Eâ'mail with mail 254

Managing Eâ'mail with mutt 256

Summary 257

Chapter 13: Doing Remote System Administration 259

Doing Remote Login and Tunneling with SSH 259

Using Legacy Communications Tools 260

Configuring SSH 261

Logging in Remotely with ssh 262

Using byobu and screen for Remote Shells 267

Managing Remote Shells with Screen 268

Using byobu to Manage Remote Shells 270

Using a Remote Windows Desktop 272

Connecting to a Windows Desktop with Remmina 272

Connecting to a Windows Desktop with rdesktop 274

Using Remote Linux Desktop and Applications 274

Sharing Desktops Using VNC 275

Setting Up the VNC Server 276

Starting Up the VNC Client 277

Using VNC on Untrusted Networks with SSH 277

Summary 278

Chapter 14: Locking Down Security 279

Working with Users and Groups 279

Managing Users the GUI Way 280

Adding User Accounts 280

Changing useradd Defaults 281

Modifying User Accounts 282

Deleting User Accounts 283

Managing Passwords 283

Adding Groups 286

Checking on Users 286

Configuring the Built-In Firewall 288

Understanding iptables Firewalls 289

Listing iptables Rules 291

Setting Other Firewall Rules 292

Saving and Reloading Firewall Rules 294

Using Advanced Security Features 294

Summary 295

Chapter 15: Setting Up a Virtualization Host and Virtual Machines 297

Can Your Computer Support Virtualization? 298

Checking for CPU Virtualization Support 298

Enabling Virtualization Support in the BIOS 299

Is the Host Computer 32- or 64-Bit? 300

Checking Available RAM and Disk Space 300

Adding Virtualization Software 301

Adding Your User Account to libvirtd 302

Managing Virtual Machines with virt-manager 302

Creating a Virtual Machine in virt-manager 304

Starting and Stopping Virtual Machines with virt-manager 305

Managing Virtual Machines with Commands 306

Creating a Virtual Machine with virt-install 306

Starting and Stopping Virtual Machines with virsh 308

Summary 309

Appendix A: Using vi or Vim Editors 311

Starting and Quitting the vi Editor 311

Moving Around in vi 313

Changing and Deleting Text in vi 314

Using Miscellaneous Commands 314

Modifying Commands with Numbers 315

Using ex Commands 315

Working in Visual Mode 316

Appendix B: Shell Special Characters and Variables 317

Using Special Shell Characters 317

Using Shell Variables 318

Appendix C: Getting Information from /proc 321

Viewing /proc Information 321

Changing /proc Information 325

Index 327