Reference openSUSE Leap 42.3 Reference openSUSE Leap 42.3 Publication Date: November 05, 2018 SUSE LLC 10 Canal Park Drive Suite 200 Cambridge MA 02141 USA https://www.suse.com/documentation Copyright © 2006– 2018 SUSE LLC and contributors. All rights reserved. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Docu- mentation License, Version 1.2 or (at your option) version 1.3; with the Invariant Section being this copyright notice and license. A copy of the license version 1.2 is included in the section entitled “GNU Free Documentation License”. For SUSE trademarks, see http://www.suse.com/company/legal/ . All other third-party trademarks are the prop- erty of their respective owners. Trademark symbols (®, ™ etc.) denote trademarks of SUSE and its affiliates. Asterisks (*) denote third-party trademarks. All information found in this book has been compiled with utmost attention to detail. However, this does not guarantee complete accuracy. Neither SUSE LLC, its affiliates, the authors nor the translators shall be held liable for possible errors or the consequences thereof. Contents About This Guide xvi I ADVANCED ADMINISTRATION 1 1 YaST in Text Mode 2 1.1 Navigation in Modules 3 1.2 Advanced Key Combinations 5 1.3 Restriction of Key Combinations 5 1.4 YaST Command Line Options 6 Starting the Individual Modules 6 • Installing Packages from the Command Line 6 • Command Line Parameters of the YaST Modules 7 2 Managing Software with Command Line Tools 8 2.1 Using Zypper 8 General Usage 8 • Installing and Removing Software with Zypper 10 • Updating Software with Zypper 14 • Identifying Processes and Services Using Deleted Files 18 • Managing Repositories with Zypper 19 • Querying Repositories and Packages with Zypper 21 • Configuring Zypper 23 • Troubleshooting 23 • Zypper Rollback Feature on Btrfs File System 24 • For More Information 24 2.2 RPM—the Package Manager 24 Verifying Package Authenticity 25 • Managing Packages: Install, Update, and Uninstall 25 • Delta RPM Packages 27 • RPM Queries 27 • Installing and Compiling Source Packages 30 • Compiling RPM Packages with build 32 • Tools for RPM Archives and the RPM Database 33 iii Reference 3 System Recovery and Snapshot Management with Snapper 34 3.1 Default Setup 34 Types of Snapshots 36 • Directories That Are Excluded from Snapshots 36 • Customizing the Setup 38 3.2 Using Snapper to Undo Changes 41 Undoing YaST and Zypper Changes 42 • Using Snapper to Restore Files 47 3.3 System Rollback by Booting from Snapshots 49 Snapshots after Rollback 51 • Accessing and Identifying Snapshot Boot Entries 52 • Limitations 54 3.4 Creating and Modifying Snapper Configurations 55 Managing Existing Configurations 57 3.5 Manually Creating and Managing Snapshots 60 Snapshot Metadata 60 • Creating Snapshots 62 • Modifying Snapshot Metadata 63 • Deleting Snapshots 64 3.6 Automatic Snapshot Clean-Up 65 Cleaning Up Numbered Snapshots 66 • Cleaning Up Timeline Snapshots 67 • Cleaning Up Snapshot Pairs That Do Not Differ 69 • Cleaning Up Manually Created Snapshots 69 • Adding Disk Quota Support 70 3.7 Frequently Asked Questions 71 4 Remote Access with VNC 73 4.1 The vncviewer Client 73 Connecting Using the vncviewer CLI 73 • Connecting Using the vncviewer GUI 74 • Notification of Unencrypted Connections 74 4.2 Remmina: the Remote Desktop Client 75 Installation 75 • Main Window 75 • Adding Remote Sessions 75 • Starting Remote Sessions 77 • Editing, Copying, and Deleting Saved Sessions 78 • Running Remote Sessions from the Command Line 78 iv Reference 4.3 One-time VNC Sessions 79 Available Configurations 80 • Initiating a One-time VNC Session 81 • Configuring One-time VNC Sessions 81 4.4 Persistent VNC Sessions 82 VNC Session Initiated using vncserver 82 • VNC Session Initiated using vncmanager 84 4.5 Encrypted VNC Communication 87 5 Advanced Disk Setup 90 5.1 Using the YaST Partitioner 90 Partition Types 92 • Creating a Partition 92 • Editing a Partition 96 • Expert Options 98 • Advanced Options 99 • More Partitioning Tips 99 • Partitioning and LVM 102 5.2 LVM Configuration 102 LVM Configuration with YaST 103 5.3 Soft RAID Configuration with YaST 106 Soft RAID Configuration with YaST 106 • Troubleshooting 108 • For More Information 108 6 Installing Multiple Kernel Versions 109 6.1 Enabling and Configuring Multiversion Support 109 Automatically Deleting Unused Kernels 110 • Use Case: Deleting an Old Kernel after Reboot Only 111 • Use Case: Keeping Older Kernels as Fallback 111 • Use Case: Keeping a Specific Kernel Version 112 6.2 Installing/Removing Multiple Kernel Versions with YaST 112 6.3 Installing/Removing Multiple Kernel Versions with Zypper 113 6.4 Installing the Latest Kernel Version from the Repository Kernel:HEAD 114 7 GNOME Configuration for Administrators 115 7.1 Starting Applications Automatically 115 7.2 Automounting and Managing Media Devices 115 v Reference 7.3 Changing Preferred Applications 115 7.4 Adding Document Templates 116 7.5 For More Information 116 II SYSTEM 117 8 32-Bit and 64-Bit Applications in a 64-Bit System Environment 118 8.1 Runtime Support 118 8.2 Software Development 119 8.3 Software Compilation on Biarch Platforms 120 8.4 Kernel Specifications 121 9 Introduction to the Booting Process 122 9.1 The Linux Boot Process 122 9.2 initramfs 124 9.3 Init on initramfs 125 10 The systemd Daemon 128 10.1 The systemd Concept 128 What Is systemd 128 • Unit File 129 10.2 Basic Usage 130 Managing Services in a Running System 130 • Permanently Enabling/ Disabling Services 132 10.3 System Start and Target Management 134 Targets Compared to Runlevels 134 • Debugging System Start- Up 137 • System V Compatibility 140 10.4 Managing Services with YaST 141 vi Reference 10.5 Customization of systemd 142 Customizing Service Files 143 • Creating “Drop-in” Files 143 • Creating Custom Targets 143 10.6 Advanced Usage 144 Cleaning Temporary Directories 144 • System Log 145 • Snapshots 145 • Loading Kernel Modules 146 • Performing Actions before Loading a Service 146 • Kernel Control Groups (cgroups) 147 • Terminating Services (Sending Signals) 148 • Debugging Services 149 10.7 More Information 150 11 journalctl: Query the systemd Journal 151 11.1 Making the Journal Persistent 151 11.2 journalctl Useful Switches 152 11.3 Filtering the Journal Output 153 Filtering Based on a Boot Number 153 • Filtering Based on Time Interval 153 • Filtering Based on Fields 154 11.4 Investigating systemd Errors 155 11.5 Journald Configuration 156 Changing the Journal Size Limit 156 • Forwarding the Journal to /dev/ ttyX 156 • Forwarding the Journal to Syslog Facility 157 11.6 Using YaST to Filter the systemd Journal 157 12 The Boot Loader GRUB 2 159 12.1 Main Differences between GRUB Legacy and GRUB 2 159 12.2 Configuration File Structure 159 The File /boot/grub2/grub.cfg 161 • The File /etc/default/ grub 161 • Scripts in /etc/grub.d 164 • Mapping between BIOS Drives and Linux Devices 165 • Editing Menu Entries during the Boot Procedure 166 • Setting a Boot Password 167 vii Reference 12.3 Configuring the Boot Loader with YaST 168 Boot Loader Location and Boot Code Options 169 • Adjusting the Disk Order 171 • Configuring Advanced Options 171 12.4 Differences in Terminal Usage on z Systems 174 Limitations 174 • Key Combinations 174 12.5 Helpful GRUB 2 Commands 176 12.6 More Information 178 13 Basic Networking 179 13.1 IP Addresses and Routing 182 IP Addresses 182 • Netmasks and Routing 182 13.2 IPv6—The Next Generation Internet 184 Advantages 185 • Address Types and Structure 186 • Coexistence of IPv4 and IPv6 190 • Configuring IPv6 191 • For More Information 192 13.3 Name Resolution 193 13.4 Configuring a Network Connection with YaST 194 Configuring the Network Card with YaST 194 13.5 NetworkManager 205 NetworkManager and wicked 205 • NetworkManager Functionality and Configuration Files 206 • Controlling and Locking Down NetworkManager Features 207 13.6 Configuring a Network Connection Manually 207 The wicked Network Configuration 207 • Configuration Files 214 • Testing the Configuration 225 • Unit Files and Start-Up Scripts 228 13.7 Basic Router Setup 230 13.8 Setting Up Bonding Devices 231 Hotplugging of Bonding Slaves 233 13.9 Setting Up Team Devices for Network Teaming 234 Use Case: Loadbalancing with Network Teaming 238 • Use Case: Failover with Network Teaming 239 • Use Case: VLAN over Team Device 240 viii Reference 13.10 Software-Defined Networking with Open vSwitch 242 Advantages of Open vSwitch 242 • Installing Open vSwitch 243 • Overview of Open vSwitch Daemons and Utilities 243 • Creating a Bridge with Open vSwitch 244 • Using Open vSwitch Directly with KVM 245 • Using Open vSwitch with libvirt 247 • For More Information 248 14 UEFI (Unified Extensible Firmware Interface) 249 14.1 Secure Boot 249 Implementation on openSUSE Leap 250 • MOK (Machine Owner Key) 254 • Booting a Custom Kernel 254 • Using Non-Inbox Drivers 256 • Features and Limitations 257 14.2 For More Information 258 15 Special System Features 259 15.1 Information about Special Software Packages 259 The bash Package and /etc/profile 259 • The cron Package 260 • Stopping Cron Status Messages 261 • Log Files: Package logrotate 261 • The locate Command 261 • The ulimit Command 262 • The free Command 263 • Man Pages and Info Pages 263 • Selecting Man Pages Using the man Command 263 • Settings for GNU Emacs 264 15.2 Virtual Consoles 265 15.3 Keyboard Mapping 265 15.4 Language and Country-Specific Settings 266 Some Examples 267 • Locale Settings in ~/.i18n 268 • Settings for Language Support