Linux in Action (MEAP - Early Edition)

Linux in Action MEAP V05......Page 1
Copyright......Page 2
Welcome......Page 3
Brief contents......Page 4
Chapter 1: Welcome to Linux......Page 5
1.1    What makes Linux different from other operating systems......Page 6
1.2.1   The Linux file system......Page 7
1.2.2   Getting around: Linux navigation tools......Page 10
1.2.3   Getting things done: Linux file management tools......Page 14
1.2.4   Keyboard tricks......Page 18
1.2.5   Pseudo File Systems......Page 19
1.2.6   Showing 'em who’s boss: sudo......Page 20
1.3.1   Man......Page 21
1.3.2   Info......Page 22
1.3.3   The Internet......Page 23
1.5    Definitions......Page 24
1.8    Test yourself......Page 25
1.8.1  Answer Key:......Page 26
Chapter 2: Linux virtualization: building a safe and simple Linux working environment......Page 27
2.1    What is virtualization?......Page 28
2.1.1   How virtualization works......Page 29
2.2.1   Working with Linux package managers......Page 31
2.2.2   Defining a virtual machine......Page 37
2.2.3   Installing an Operating System......Page 42
2.2.4   Cloning and sharing a VirtualBox VM......Page 45
2.3.1   Getting started with LXC......Page 47
2.4    Summary......Page 51
2.7  Command line review......Page 52
2.8  Test yourself......Page 53
2.8.1   Answer Key:......Page 54
3.1    The importance of encryption......Page 55
3.2.1   The OpenSSH package......Page 57
3.3    Logging into a remote server with SSH......Page 59
3.4    Password-free SSH access......Page 61
3.4.1   Generating a new key pair......Page 62
3.4.2   Copying the public key over a network......Page 63
3.5    Safely copying files with scp......Page 65
3.6    Using remote graphic programs over SSH connections......Page 66
3.7    Linux process management......Page 68
3.7.1   Viewing processes with the ps command......Page 69
3.7.2   Working with systemd......Page 71
3.10   Security best practices......Page 72
3.12  Test yourself......Page 73
3.12.1  Answer Key:......Page 74
4.1    Why archive?......Page 75
4.1.2   Archives: some important considerations......Page 77
4.2.1   Identifying partitions on a Linux file system......Page 79
4.3    Where to back up......Page 81
4.4.1   Simple archive and compression examples......Page 82
4.4.2   Streaming file system archives......Page 83
4.4.3   Aggregating files......Page 86
4.4.4   Preserving permissions and ownership…and extracting archives......Page 87
4.5.1   dd operations......Page 92
4.6    Synchronizing archives with rsync......Page 93
4.8    Summary......Page 95
4.11  Command line review......Page 96
4.12  Test yourself......Page 97
4.12.1   Answer Key:......Page 98
Chapter 5: Automated administration: configure automated offsite backups......Page 99
5.1.1   A sample script......Page 100
5.2    Back up data to AWS S3......Page 105
5.2.1   Install the AWS command line interface (CLI)......Page 106
5.3    Schedule regular backups with cron......Page 109
5.4    Schedule irregular backups with anacron......Page 111
5.4.1   Running the S3 sync job......Page 112
5.5    Schedule regular backups with systemd timers......Page 113
5.8    Security best practices......Page 115
5.10  Test yourself......Page 116
5.10.1  Answer Key:......Page 117
Chapter 6: Emergency tools: build a system recovery device......Page 118
6.1    Working in recovery/rescue mode......Page 119
6.1.1   The GRUB bootloader......Page 120
6.1.3   Using rescue mode on CentOS......Page 121
6.1.4   Finding command line rescue tools......Page 122
6.2.1   System rescue images......Page 124
6.2.2   Writing live-boot images to USB drives......Page 125
6.3.1   Test system memory......Page 130
6.3.2   Damaged partitions......Page 132
6.3.3   Recovering files from a damaged file system......Page 134
6.4    Chroot: mounting a file system as a process......Page 136
6.8    Command line review......Page 138
6.9    Test yourself......Page 139
6.9.1   Answer Key:......Page 140
Chapter 7: Web servers - build a MediaWiki server......Page 141
7.1    Building a LAMP server?......Page 142
7.2    Setting up an Apache web server......Page 143
7.2.1   Installing the Apache web server on Ubuntu......Page 144
7.2.2   Installing the Apache web server (httpd) on CentOS......Page 145
7.2.3   Understanding network ports......Page 146
7.2.5   Populating your website document root......Page 147
7.3    Installing an SQL database......Page 148
7.3.1   SQL administration......Page 151
7.4.1   Installing PHP on Ubuntu......Page 153
7.4.2   Installing PHP on CentOS......Page 154
7.5    Installing and configuring MediaWiki......Page 156
7.5.1   Troubleshooting missing extensions......Page 157
7.5.2   Connecting MediaWiki to the database......Page 160
7.7    Key terms......Page 162
7.10  Test yourself......Page 163
7.10.1  Answer Key:......Page 165
Chapter 8: Networked file sharing - build a Nextcloud file sharing server......Page 166
8.2    Installing Nextcloud using snaps......Page 167
8.3.1   Hardware prerequisites......Page 170
8.3.3   Apache configuration......Page 172
8.3.4   Downloading and unpacking Nextcloud......Page 175
8.4    Administrating Nextcloud......Page 178
8.5    Using AWS S3 as primary Nextcloud storage......Page 182
8.5.1   Connect Nextcloud to an S3 bucket......Page 183
8.9    Command line review......Page 185
8.10  Test yourself......Page 186
8.10.1  Answer Key:......Page 187
Chapter 9: Securing your web server......Page 188
9.1    The obvious stuff......Page 189
9.2.1   Configuring a firewall......Page 190
9.2.2   Using non-standard ports......Page 197
9.3    Encrypting data in transit......Page 199
9.3.1   Preparing your website domain......Page 201
9.3.2   Generating certificates using Let’s Encrypt......Page 202
9.4    Hardening the authentication process......Page 203
9.4.1   Controlling file system objects with SELinux......Page 204
9.4.2   Installing and activating SELinux......Page 205
9.4.3   Applying SELinux policies......Page 207
9.4.4   System groups and the principle of least privilege......Page 208
9.4.6   Scanning for dangerous user ID values......Page 211
9.5.1   Scanning for open ports......Page 212
9.5.2   Scanning for active services......Page 213
9.7    Key terms......Page 214
9.9    Test yourself......Page 215
9.9.1   Answer Key:......Page 216
Chapter 10: Securing your network connections - create a VPN or DMZ......Page 217
10.1  Building an OpenVPN tunnel......Page 218
10.1.1   Configuring an OpenVPN server......Page 219
10.1.2   Configuring an OpenVPN client......Page 226
10.1.3   Testing your VPN......Page 228
10.2  Building intrusion-resistant networks......Page 229
10.2.1  Demilitarized zones (DMZs)......Page 230
10.2.2  Resistant networks: design considerations......Page 231
10.2.3   Using iptables......Page 233
10.2.4   Create a DMZ using Shorewall......Page 236
10.3  Building a virtual network for infrastructure testing......Page 239
10.5  Key terms......Page 241
10.7  Test yourself......Page 242
10.7.1   Answer Key:......Page 244
Chapter 11: System monitoring - working with log files......Page 245
11.1  Working with system logs......Page 246
11.1.1   Logging with journald......Page 247
11.1.2   Logging with syslogd......Page 249
11.2.1   The journald way......Page 251
11.2.2   The syslogd way......Page 252
11.3.1   grep......Page 253
11.3.2   awk......Page 254
11.3.3   sed......Page 256
11.4  Intrusion detection......Page 257
11.4.2   Installing Tripwire......Page 258
11.4.3   Configuring Tripwire......Page 261
11.5  Summary:......Page 264
11.8  Command line review......Page 265
11.9  Test yourself......Page 266
11.9.1  Answer Key:......Page 267
Chapter 12: Sharing data over a private network......Page 268
12.1  Sharing files through the Network File System (NFS)......Page 269
12.1.1   Setting up the NFS server......Page 270
12.1.2   Setting up the client......Page 272
12.1.3   Mounting an NFS share at boot time......Page 273
12.1.4   NFS security......Page 274
12.2  Samba: sharing files with Windows users......Page 276
12.2.1   Testing your Samba configuration......Page 278
12.2.2   Accessing a Samba server from Windows......Page 279
12.3  Symbolic links: sharing files with yourself......Page 280
12.3.1   Symbolic vs. hard links......Page 281
12.6  Security best practices......Page 282
12.8  Test yourself......Page 283
12.8.1   Answer Key:......Page 284
Chapter 13: Troubleshooting system performance issues......Page 285
13.1.1  Measuring CPU load......Page 286
13.1.2   Managing CPU loads......Page 287
13.1.3   Making trouble (simulating CPU load)......Page 290
13.2.1   Assessing memory status......Page 291
13.3    Storage availability problems......Page 292
13.3.1   Inode limits......Page 293
13.4.1   Measuring bandwidth......Page 296
13.4.3   Shaping network traffic with tc......Page 298
13.5.1  Aggregating monitoring data......Page 300
13.7    Key terms......Page 303
13.10 Test yourself......Page 304
13.10.1 Answer Key:......Page 306
Chapter 14: Troubleshooting network issues......Page 307
14.1.1   NAT addressing......Page 308
14.2    Establishing network connectivity......Page 311
14.3.1   Tracking down the status of your network......Page 313
14.3.2   Assigning IP addresses......Page 315
14.3.3   Configuring DNS service......Page 318
14.3.4   Plumbing......Page 320
14.4.1   netstat: internal connection scanning......Page 321
14.4.2   netcat: external connection scanning......Page 322
14.5    Summary......Page 323
14.8    Command line review......Page 324
14.9    Test yourself......Page 325
14.9.1   Answer Key:......Page 326
Chapter 15: Troubleshooting peripheral devices......Page 327
15.1    Identifying attached devices......Page 328
15.2    Managing peripherals with Linux kernel modules......Page 330
15.2.1   Finding kernel modules......Page 331
15.2.2   Manually loading kernel modules......Page 333
15.3.1   Passing parameters at boot time......Page 335
15.4.1   Basics of lp......Page 337
15.4.2   Managing printers using CUPS......Page 338
15.6    Key terms......Page 340
15.9    Test yourself......Page 341
15.9.1   Answer Key:......Page 342
Chapter 16: DevOps tools: deploy a scripted server environment using Ansible......Page 343
16.1 What can deployment orchestrators do for you......Page 345
16.2 Ansible: installation and setup......Page 346
16.2.1 Organize Ansible hosts......Page 347
16.3 Authentication......Page 349
16.3.1 Administrating remote hosts using permissions......Page 350
16.4.1 Write a simple playbook......Page 351
16.4.2 Multi-tiered, roles-powered playbooks......Page 354
16.4.3 Managing passwords in Ansible......Page 356
16.8 Command line review......Page 357
16.9.1 Answer Key:......Page 358