Applies to openSUSE Leap 42.2

Part II System

8 32-Bit and 64-Bit Applications in a 64-Bit System Environment

openSUSE® Leap is available for 64-bit platforms. This does not necessarily mean that all the applications included have already been ported to 64-bit platforms. openSUSE Leap supports the use of 32-bit applications in a 64-bit system environment. This chapter offers a brief overview of how this sup…

9 Booting a Linux System

Booting a Linux system involves different components and tasks. The hardware itself is initialized by the BIOS or the UEFI, which starts the Kernel by means of a boot loader. After this point, the boot process is completely controlled by the operating system and handled by systemd. systemd provides a set of targets that boot setups for everyday usage, maintenance or emergencies.

10 The systemd Daemon

The program systemd is the process with process ID 1. It is responsible for initializing the system in the required way. systemd is started directly by the Kernel and resists signal 9, which normally terminates processes. All other programs are either started directly by systemd or by one of its chi…

11 journalctl: Query the systemd Journal

When systemd replaced traditional init scripts in SUSE Linux Enterprise 12 (see Chapter 10, The systemd Daemon), it introduced its own logging system called journal. There is no need to run a syslog based service anymore, as all system events are written in the journal.

12 The Boot Loader GRUB 2

This chapter describes how to configure GRUB 2, the boot loader used in openSUSE® Leap. It is the successor of the traditional GRUB boot loader—now called GRUB Legacy. A YaST module is available for configuring the most important settings. The boot procedure as a whole is outlined in Chapter 9, Booting a Linux System. For details on Secure Boot support for UEFI machines, see Chapter 14, UEFI (Unified Extensible Firmware Interface).

13 Basic Networking

Linux offers the necessary networking tools and features for integration into all types of network structures. Network access using a network card can be configured with YaST. Manual configuration is also possible. In this chapter only the fundamental mechanisms and the relevant network configuration files are covered.

14 UEFI (Unified Extensible Firmware Interface)

UEFI (Unified Extensible Firmware Interface) is the interface between the firmware that comes with the system hardware, all the hardware components of the system, and the operating system.

15 Special System Features

This chapter starts with information about various software packages, the virtual consoles and the keyboard layout. We talk about software components like bash, cron and logrotate, because they were changed or enhanced during the last release cycles. Even if they are small or considered of minor importance, users should change their default behavior, because these components are often closely coupled with the system. The chapter concludes with a section about language and country-specific settings (I18N and L10N).

16 Dynamic Kernel Device Management with udev

The kernel can add or remove almost any device in a running system. Changes in the device state (whether a device is plugged in or removed) need to be propagated to user space. Devices need to be configured as soon as they are plugged in and recognized. Users of a certain device need to be informed …