Jump to contentJump to page navigation: previous page [access key p]/next page [access key n]
SUSE Linux Enterprise Server 12 SP5

Administration Guide

Covers system administration tasks like maintaining, monitoring and customizing an initially installed system.

Publication Date: January 21, 2022
About This Guide
Available Documentation
Giving Feedback
Documentation Conventions
Product Life Cycle and Support
I Common Tasks
1 Bash and Bash Scripts
1.1 What is The Shell?
1.2 Writing Shell Scripts
1.3 Redirecting Command Events
1.4 Using Aliases
1.5 Using Variables in Bash
1.6 Grouping and Combining Commands
1.7 Working with Common Flow Constructs
1.8 For More Information
2 sudo
2.1 Basic sudo Usage
2.2 Configuring sudo
2.3 Common Use Cases
2.4 More Information
3 YaST Online Update
3.1 The Online Update Dialog
3.2 Installing Patches
3.3 Automatic Online Update
4 YaST
4.1 Advanced Key Combinations
5 YaST in Text Mode
5.1 Navigation in Modules
5.2 Advanced Key Combinations
5.3 Restriction of Key Combinations
5.4 YaST Command Line Options
6 Managing Software with Command Line Tools
6.1 Using Zypper
6.2 RPM—the Package Manager
7 System Recovery and Snapshot Management with Snapper
7.1 Default Setup
7.2 Using Snapper to Undo Changes
7.3 System Rollback by Booting from Snapshots
7.4 Enabling Snapper in User Home Directories
7.5 Creating and Modifying Snapper Configurations
7.6 Manually Creating and Managing Snapshots
7.7 Automatic Snapshot Clean-Up
7.8 Frequently Asked Questions
8 Remote Access with VNC
8.1 The vncviewer Client
8.2 Remmina: the Remote Desktop Client
8.3 One-time VNC Sessions
8.4 Persistent VNC Sessions
8.5 Encrypted VNC Communication
9 File Copying with RSync
9.1 Conceptual Overview
9.2 Basic Syntax
9.3 Copying Files and Directories Locally
9.4 Copying Files and Directories Remotely
9.5 Configuring and Using an Rsync Server
9.6 For More Information
10 GNOME Configuration for Administrators
10.1 Starting Applications Automatically
10.2 Automounting and Managing Media Devices
10.3 Changing Preferred Applications
10.4 Adding Document Templates
10.5 For More Information
II Booting a Linux System
11 Introduction to the Boot Process
11.1 Terminology
11.2 The Linux Boot Process
12 UEFI (Unified Extensible Firmware Interface)
12.1 Secure Boot
12.2 For More Information
13 The Boot Loader GRUB 2
13.1 Main Differences between GRUB Legacy and GRUB 2
13.2 Configuration File Structure
13.3 Configuring the Boot Loader with YaST
13.4 Differences in Terminal Usage on IBM Z
13.5 Helpful GRUB 2 Commands
13.6 More Information
14 The systemd Daemon
14.1 The systemd Concept
14.2 Basic Usage
14.3 System Start and Target Management
14.4 Managing Services with YaST
14.5 Customization of systemd
14.6 Advanced Usage
14.7 More Information
III System
15 32-Bit and 64-Bit Applications in a 64-Bit System Environment
15.1 Runtime Support
15.2 Kernel Specifications
16 journalctl: Query the systemd Journal
16.1 Making the Journal Persistent
16.2 journalctl Useful Switches
16.3 Filtering the Journal Output
16.4 Investigating systemd Errors
16.5 Journald Configuration
16.6 Using YaST to Filter the systemd Journal
17 Basic Networking
17.1 IP Addresses and Routing
17.2 IPv6—The Next Generation Internet
17.3 Name Resolution
17.4 Configuring a Network Connection with YaST
17.5 NetworkManager
17.6 Configuring a Network Connection Manually
17.7 Basic Router Setup
17.8 Setting Up Bonding Devices
17.9 Setting Up Team Devices for Network Teaming
17.10 Software-Defined Networking with Open vSwitch
18 Printer Operation
18.1 The CUPS Workflow
18.2 Methods and Protocols for Connecting Printers
18.3 Installing the Software
18.4 Network Printers
18.5 Configuring CUPS with Command Line Tools
18.6 Printing from the Command Line
18.7 Special Features in SUSE Linux Enterprise Server
18.8 Troubleshooting
19 The X Window System
19.1 Installing and Configuring Fonts
19.2 For More Information
20 Accessing File Systems with FUSE
20.1 Configuring FUSE
20.2 Mounting an NTFS Partition
20.3 For More Information
21 Managing Kernel Modules
21.1 Listing Loaded Modules with lsmod and modinfo
21.2 Adding and Removing Kernel Modules
22 Dynamic Kernel Device Management with udev
22.1 The /dev Directory
22.2 Kernel uevents and udev
22.3 Drivers, Kernel Modules and Devices
22.4 Booting and Initial Device Setup
22.5 Monitoring the Running udev Daemon
22.6 Influencing Kernel Device Event Handling with udev Rules
22.7 Persistent Device Naming
22.8 Files used by udev
22.9 For More Information
23 Live Patching the Linux Kernel Using kGraft
23.1 Advantages of kGraft
23.2 Low-level Function of kGraft
23.3 Installing kGraft Patches
23.4 Patch Life Cycle
23.5 Removing a kGraft Patch
23.6 Stuck Kernel Execution Threads
23.7 The kgr Tool
23.8 Scope of kGraft Technology
23.9 Scope of SLE Live Patching
23.10 Interaction with the Support Processes
24 Special System Features
24.1 Information about Special Software Packages
24.2 Virtual Consoles
24.3 Keyboard Mapping
24.4 Language and Country-Specific Settings
25 Persistent Memory
25.1 Introduction
25.2 Terms
25.3 Use Cases
25.4 Tools for Managing Persistent Memory
25.5 Setting Up Persistent Memory
25.6 Troubleshooting
25.7 For More Information
IV Services
26 Time Synchronization with NTP
26.1 Configuring an NTP Client with YaST
26.2 Manually Configuring NTP in the Network
26.3 Setting Up a Local Reference Clock
26.4 Clock Synchronization to an External Time Reference (ETR)
27 The Domain Name System
27.1 DNS Terminology
27.2 Installation
27.3 Configuration with YaST
27.4 Starting the BIND Name Server
27.5 The /etc/named.conf Configuration File
27.6 Zone Files
27.7 Dynamic Update of Zone Data
27.8 Secure Transactions
27.9 DNS Security
27.10 For More Information
28.1 Configuring a DHCP Server with YaST
28.2 DHCP Software Packages
28.3 The DHCP Server dhcpd
28.4 For More Information
29 Sharing File Systems with NFS
29.1 Overview
29.2 Installing NFS Server
29.3 Configuring NFS Server
29.4 Configuring Clients
29.5 For More Information
30 Samba
30.1 Terminology
30.2 Installing a Samba Server
30.3 Starting and Stopping Samba
30.4 Configuring a Samba Server
30.5 Configuring Clients
30.6 Samba as Login Server
30.7 Samba Server in the Network with Active Directory
30.8 Advanced Topics
30.9 For More Information
31 On-Demand Mounting with Autofs
31.1 Installation
31.2 Configuration
31.3 Operation and Debugging
31.4 Auto-Mounting an NFS Share
31.5 Advanced Topics
32 SLP
32.1 The SLP Front-End slptool
32.2 Providing Services via SLP
32.3 For More Information
33 The Apache HTTP Server
33.1 Quick Start
33.2 Configuring Apache
33.3 Starting and Stopping Apache
33.4 Installing, Activating, and Configuring Modules
33.5 Enabling CGI Scripts
33.6 Setting Up a Secure Web Server with SSL
33.7 Running Multiple Apache Instances on the Same Server
33.8 Avoiding Security Problems
33.9 Troubleshooting
33.10 For More Information
34 Setting Up an FTP Server with YaST
34.1 Starting the FTP Server
34.2 FTP General Settings
34.3 FTP Performance Settings
34.4 Authentication
34.5 Expert Settings
34.6 For More Information
35 The Proxy Server Squid
35.1 Some Facts about Proxy Caches
35.2 System Requirements
35.3 Basic Usage of Squid
35.4 The YaST Squid Module
35.5 The Squid Configuration File
35.6 Configuring a Transparent Proxy
35.7 Using the Squid Cache Manager CGI Interface (cachemgr.cgi)
35.8 squidGuard
35.9 Cache Report Generation with Calamaris
35.10 For More Information
36 Web Based Enterprise Management Using SFCB
36.1 Introduction and Basic Concept
36.2 Setting Up SFCB
36.3 SFCB CIMOM Configuration
36.4 Advanced SFCB Tasks
36.5 For More Information
V Mobile Computers
37 Mobile Computing with Linux
37.1 Laptops
37.2 Mobile Hardware
37.3 Mobile Devices (Smartphones and Tablets)
38 Using NetworkManager
38.1 Use Cases for NetworkManager
38.2 Enabling or Disabling NetworkManager
38.3 Configuring Network Connections
38.4 NetworkManager and Security
38.5 Frequently Asked Questions
38.6 Troubleshooting
38.7 For More Information
39 Power Management
39.1 Power Saving Functions
39.2 Advanced Configuration and Power Interface (ACPI)
39.3 Rest for the Hard Disk
39.4 Troubleshooting
VI Troubleshooting
40 Help and Documentation
40.1 Documentation Directory
40.2 Man Pages
40.3 Info Pages
40.4 Online Resources
41 Gathering System Information for Support
41.1 Displaying Current System Information
41.2 Collecting System Information with Supportconfig
41.3 Submitting Information to Global Technical Support
41.4 Analyzing System Information
41.5 Gathering Information during the Installation
41.6 Support of Kernel Modules
41.7 For More Information
42 Common Problems and Their Solutions
42.1 Finding and Gathering Information
42.2 Installation Problems
42.3 Boot Problems
42.4 Login Problems
42.5 Network Problems
42.6 Data Problems
42.7 IBM Z: Using initrd as a Rescue System
A An Example Network
B GNU Licenses
B.1 GNU Free Documentation License
List of Figures
3.1 YaST Online Update
5.1 Main Window of YaST in Text Mode
5.2 The Software Installation Module
7.1 Boot Loader: Snapshots
8.1 vncviewer
8.2 Remmina's Main Window
8.3 Remote Desktop Preference
8.4 Quick-starting
8.5 Remmina Viewing SLES 15 Remote Session
8.6 Reading Path to the Profile File
8.7 Remote Administration
8.8 VNC Session Settings
8.9 Joining a Persistent VNC Session
12.1 Secure Boot Support
12.2 UEFI: Secure Boot Process
13.1 GRUB 2 Boot Editor
13.2 Boot Code Options
13.3 Code Options
13.4 Boot loader Options
13.5 Kernel Parameters
14.1 Services Manager
16.1 YaST systemd Journal
17.1 Simplified Layer Model for TCP/IP
17.2 TCP/IP Ethernet Packet
17.3 Configuring Network Settings
17.4 wicked architecture
25.1 NVDIMM Region Layout
26.1 YaST: NTP Server
26.2 Advanced NTP Configuration: Security Settings
27.1 DNS Server Installation: Forwarder Settings
27.2 DNS Server Installation: DNS Zones
27.3 DNS Server Installation: Finish Wizard
27.4 DNS Server: Logging
27.5 DNS Server: Zone Editor (Basics)
27.6 DNS Server: Zone Editor (NS Records)
27.7 DNS Server: Zone Editor (MX Records)
27.8 DNS Server: Zone Editor (SOA)
27.9 Adding a Record for a Master Zone
27.10 Adding a Reverse Zone
27.11 Adding a Reverse Record
28.1 DHCP Server: Card Selection
28.2 DHCP Server: Global Settings
28.3 DHCP Server: Dynamic DHCP
28.4 DHCP Server: Start-Up
28.5 DHCP Server: Host Management
28.6 DHCP Server: Chroot Jail and Declarations
28.7 DHCP Server: Selecting a Declaration Type
28.8 DHCP Server: Configuring Subnets
28.9 DHCP Server: TSIG Configuration
28.10 DHCP Server: Interface Configuration for Dynamic DNS
28.11 DHCP Server: Network Interface and Firewall
29.1 NFS Server Configuration Tool
30.1 Determining Windows Domain Membership
30.2 Windows Explorer Advanced Attributes Dialog
30.3 Windows Explorer Directory Listing with Compressed Files
30.4 Adding a New Samba Share with Snapshotting Enabled
30.5 The Previous Versions tab in Windows Explorer
33.1 HTTP Server Wizard: Default Host
33.2 HTTP Server Wizard: Summary
33.3 HTTP Server Configuration: Listen Ports and Addresses
33.4 HTTP Server Configuration: Server Modules
34.1 FTP Server Configuration — Start-Up
36.1 Package Selection for Web-Based Enterprise Management Pattern
36.2 Package selection of additional CIM providers
37.1 Integrating a Mobile Computer in an Existing Environment
38.1 GNOME Network Connections Dialog
41.1 HTML Report Generated by SCA Tool
41.2 HTML Report Generated by SCA Appliance
42.1 Checking Media
42.2 US Keyboard Layout
List of Examples
1.1 A Shell Script Printing a Text
6.1 Zypper—List of Known Repositories
6.2 rpm -q -i wget
6.3 Script to Search for Packages
7.1 Example timeline configuration
13.1 Usage of grub2-mkconfig
13.2 Usage of grub2-mkrescue
13.3 Usage of grub2-script-check
13.4 Usage of grub2-once
14.1 List Active Services
14.2 List Failed Services
14.3 List all Processes Belonging to a Service
17.1 Writing IP Addresses
17.2 Linking IP Addresses to the Netmask
17.3 Sample IPv6 Address
17.4 IPv6 Address Specifying the Prefix Length
17.5 Common Network Interfaces and Some Static Routes
17.6 /etc/resolv.conf
17.7 /etc/hosts
17.8 /etc/networks
17.9 /etc/host.conf
17.10 /etc/nsswitch.conf
17.11 Output of the Command ping
17.12 Configuration for Loadbalancing with Network Teaming
17.13 Configuration for DHCP Network Teaming Device
18.1 Error Message from lpd
18.2 Broadcast from the CUPS Network Server
19.1 Specifying Rendering Algorithms
19.2 Aliases and Family Name Substitutions
19.3 Aliases and Family Name Substitutions
19.4 Aliases and Family Names Substitutions
22.1 Example udev Rules
24.1 Entry in /etc/crontab
24.2 /etc/crontab: Remove Time Stamp Files
24.3 ulimit: Settings in ~/.bashrc
27.1 Forwarding Options in named.conf
27.2 A Basic /etc/named.conf
27.3 Entry to Disable Logging
27.4 Zone Entry for example.com
27.5 Zone Entry for example.net
27.6 The /var/lib/named/example.com.zone File
27.7 Reverse Lookup
28.1 The Configuration File /etc/dhcpd.conf
28.2 Additions to the Configuration File
30.1 A CD-ROM Share
30.2 [homes] Share
30.3 Global Section in smb.conf
30.4 Using rpcclient to Request a Windows Server 2012 Share Snapshot
33.1 Basic Examples of Name-Based VirtualHost Entries
33.2 Name-Based VirtualHost Directives
33.3 IP-Based VirtualHost Directives
33.4 Basic VirtualHost Configuration
33.5 VirtualHost CGI Configuration
35.1 A Request With squidclient
35.2 Defining ACL Rules
41.1 Output of hostinfo When Logging In as root

Copyright © 2006– 2022 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 Documentation 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 https://www.suse.com/company/legal/. All other third-party trademarks are the property 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.

Print this page