Applies to SUSE Linux Enterprise Server 15

About This Guide #

SUSE Linux Enterprise Server is used for a broad range of usage scenarios in enterprise and scientific data centers. SUSE has ensured SUSE Linux Enterprise Server is set up in a way that it accommodates different operation purposes with optimal performance. However, SUSE Linux Enterprise Server must meet very different demands when employed on a number crunching server compared to a file server, for example.

It is not possible to ship a distribution that is optimized for all workloads. Different workloads vary substantially in some aspects. Most important among those are I/O access patterns, memory access patterns, and process scheduling. A behavior that perfectly suits a certain workload might reduce performance of another workload. For example, I/O-intensive tasks, such as handling database requests, usually have completely different requirements than CPU-intensive tasks, such as video encoding. The versatility of Linux makes it possible to configure your system in a way that it brings out the best in each usage scenario.

This manual introduces you to means to monitor and analyze your system. It describes methods to manage system resources and to tune your system. This guide does not offer recipes for special scenarios, because each server has got its own different demands. It rather enables you to thoroughly analyze your servers and make the most out of them.

Part I, “Basics”: Tuning a system requires a carefully planned proceeding. Learn which steps are necessary to successfully improve your system.
Part II, “System Monitoring”: Linux offers a large variety of tools to monitor almost every aspect of the system. Learn how to use these utilities and how to read and analyze the system log files.
Part III, “Kernel Monitoring”: The Linux kernel itself offers means to examine every nut, bolt and screw of the system. This part introduces you to SystemTap, a scripting language for writing kernel modules that can be used to analyze and filter data. Collect debugging information and find bottlenecks by using kernel probes and Perf. Last, monitor applications with Oprofile.
Part IV, “Resource Management”: Learn how to set up a tailor-made system fitting exactly the server's need. Get to know how to use power management while at the same time keeping the performance of a system at a level that matches the current requirements.
Part V, “Kernel Tuning”: The Linux kernel can be optimized either by using sysctl, via the /proc and /sys file systems or by kernel command line parameters. This part covers tuning the I/O performance and optimizing the way how Linux schedules processes. It also describes basic principles of memory management and shows how memory management can be fine-tuned to suit needs of specific applications and usage patterns. Furthermore, it describes how to optimize network performance.
Part VI, “Handling System Dumps”: This part enables you to analyze and handle application or system crashes. It introduces tracing tools such as strace or ltrace and describes how to handle system crashes using Kexec and Kdump.

Tip: Getting the SUSE Linux Enterprise SDK

The SDK is a module for SUSE Linux Enterprise and is available via an online channel from the SUSE Customer Center. Alternatively, go to http://download.suse.com/, search for SUSE Linux Enterprise Software Development Kit and download it from there. Refer to Chapter 21, Installing Modules, Extensions, and Third Party Add-On Products for details.

1 Available Documentation #

Note: Online Documentation and Latest Updates

Documentation for our products is available at http://www.suse.com/documentation/, where you can also find the latest updates, and browse or download the documentation in various formats. The latest documentation updates are usually available in the English version of the documentation.

Note: Manual Pages

Many commands are described in detail in their manual pages. You can view manual pages by running the man command followed by a specific command name. If the man command is not installed on your system, install it by running zypper install man.

The following documentation is available for this product:

Skrócona instrukcja instalacji: This Quick Start guides you step-by-step through the installation of SUSE® Linux Enterprise Server 15.
Deployment Guide: This guide details how to install single or multiple systems, and how to exploit the product-inherent capabilities for a deployment infrastructure. Choose from various approaches: local installation from physical installation media, customizing the standard installation images, network installation server, mass deployment using a remote-controlled, highly-customized, automated installation process, and initial system configuration.
Administration Guide: Covers system administration tasks like maintaining, monitoring and customizing an initially installed system.
Virtualization Guide: Describes virtualization technology in general, and introduces libvirt—the unified interface to virtualization—and detailed information on specific hypervisors.
Storage Administration Guide: Provides information about how to manage storage devices on a SUSE Linux Enterprise Server.
AutoYaST Guide: AutoYaST is a system for unattended mass deployment of SUSE Linux Enterprise Server systems using an AutoYaST profile containing installation and configuration data. The manual guides you through the basic steps of auto-installation: preparation, installation, and configuration.
Security and Hardening Guide: Introduces basic concepts of system security, covering both local and network security aspects. Shows how to use the product inherent security software like AppArmor, SELinux, or the auditing system that reliably collects information about any security-relevant events. Supports the administrator with security-related choices and decisions in installing and setting up a secure SUSE Linux Enterprise Server and additional processes to further secure and harden that installation.
System Analysis and Tuning Guide: An administrator's guide for problem detection, resolution and optimization. Find how to inspect and optimize your system by means of monitoring tools and how to efficiently manage resources. Also contains an overview of common problems and solutions and of additional help and documentation resources.
RMT Guide: An administrator's guide to Subscription Management Tool—a proxy system for SUSE Customer Center with repository and registration targets. Learn how to install and configure a local SMT server, mirror and manage repositories, manage client machines, and configure clients to use SMT.
GNOME User Guide: Introduces the GNOME desktop of SUSE Linux Enterprise Server. It guides you through using and configuring the desktop and helps you perform key tasks. It is intended mainly for end users who want to make efficient use of GNOME as their default desktop.

The release notes for this product are available at https://www.suse.com/releasenotes/.

2 Improving the Documentation #

Your feedback and contributions to this documentation are welcome. The following channels for giving feedback are available:

Service Requests and Support

For services and support options available for your product, see https://www.suse.com/support/.

To open a service request, you need a SUSE subscription registered at SUSE Customer Center. Go to https://scc.suse.com/support/requests, log in, and click Create New.

Bug Reports

Report issues with the documentation at https://bugzilla.suse.com/. To simplify this process, you can use the Report Documentation Bug links next to headlines in the HTML version of this document. These preselect the right product and category in Bugzilla and add a link to the current section. You can start typing your bug report right away. A Bugzilla account is required.

Contributions

To contribute to this documentation, use the Edit Source links next to headlines in the HTML version of this document. They take you to the source code on GitHub, where you can open a pull request. A GitHub account is required.

Note: Edit Source only available for English

The Edit Source links are only available for the English version of each document. For all other languages, use the Report Documentation Bug links instead.

For more information about the documentation environment used for this documentation, see the repository's README at https://github.com/SUSE/doc-sle/blob/main/README.adoc

Mail

You can also report errors and send feedback concerning the documentation to <doc-team@suse.com>. Include the document title, the product version, and the publication date of the document. Additionally, include the relevant section number and title (or provide the URL) and provide a concise description of the problem.

3 Documentation Conventions #

The following notices and typographical conventions are used in this documentation:

/etc/passwd: directory names and file names
PLACEHOLDER: replace PLACEHOLDER with the actual value
PATH: the environment variable PATH
ls, --help: commands, options, and parameters
user: users or groups
package name : name of a package
Alt, Alt–F1: a key to press or a key combination; keys are shown in uppercase as on a keyboard
File, File › Save As: menu items, buttons
AMD/Intel This paragraph is only relevant for the AMD64/Intel 64 architecture. The arrows mark the beginning and the end of the text block.
IBM Z, POWER This paragraph is only relevant for the architectures IBM Z and POWER. The arrows mark the beginning and the end of the text block.
Dancing Penguins (Chapter Penguins, ↑Another Manual): This is a reference to a chapter in another manual.
Commands that must be run with root privileges. Often you can also prefix these commands with the sudo command to run them as non-privileged user.
```
# command
> sudo command
```
Commands that can be run by non-privileged users.
```
> command
```
Notices
Warning: Warning Notice
Vital information you must be aware of before proceeding. Warns you about security issues, potential loss of data, damage to hardware, or physical hazards.
Important: Important Notice
Important information you should be aware of before proceeding.
Note: Note Notice
Additional information, for example about differences in software versions.
Tip: Tip Notice
Helpful information, like a guideline or a piece of practical advice.

4 Product Life Cycle and Support #

SUSE products are supported for up to 13 years. To check the life cycle dates for your product, see https://www.suse.com/lifecycle/.

For SUSE Linux Enterprise, the following life cycles and release cycles apply:

SUSE Linux Enterprise Server has a 13-year life cycle: 10 years of general support and three years of extended support.
SUSE Linux Enterprise Desktop has a 10-year life cycle: seven years of general support and three years of extended support.
Major releases are published every four years. Service packs are published every 12-14 months.
SUSE supports previous SUSE Linux Enterprise service packs for six months after the release of a new service pack.

For some products, Long Term Service Pack Support (LTSS) is available. Find information about our support policy and options at https://www.suse.com/support/policy.html and https://www.suse.com/support/programs/long-term-service-pack-support.html.

Modules have a different life cycle, update policy, and update timeline than their base products. Modules contain software packages and are fully supported parts of SUSE Linux Enterprise Server. For more information, see the Modules and Extensions Quick Start.

4.1 Support Statement for SUSE Linux Enterprise Server #

To receive support, you need an appropriate subscription with SUSE. To view the specific support offerings available to you, go to https://www.suse.com/support/ and select your product.

The support levels are defined as follows:

L1: Problem determination, which means technical support designed to provide compatibility information, usage support, ongoing maintenance, information gathering and basic troubleshooting using available documentation.
L2: Problem isolation, which means technical support designed to analyze data, reproduce customer problems, isolate problem area and provide a resolution for problems not resolved by Level 1 or prepare for Level 3.
L3: Problem resolution, which means technical support designed to resolve problems by engaging engineering to resolve product defects which have been identified by Level 2 Support.

For contracted customers and partners, SUSE Linux Enterprise Server is delivered with L3 support for all packages, except for the following:

Technology Previews
Sound, graphics, fonts and artwork.
Packages that require an additional customer contract.
Some packages shipped as part of the module Workstation Extension are L2-supported only.
Packages with names ending in -devel (containing header files and similar developer resources) will only be supported together with their main packages.

SUSE will only support the usage of original packages. That is, packages that are unchanged and not recompiled.

4.2 Technology Previews #

Technology previews are packages, stacks, or features delivered by SUSE to provide glimpses into upcoming innovations. The previews are included for your convenience to give you the chance to test new technologies within your environment. We would appreciate your feedback! If you test a technology preview, please contact your SUSE representative and let them know about your experience and use cases. Your input is helpful for future development.

However, technology previews come with the following limitations:

Technology previews are still in development. Therefore, they may be functionally incomplete, unstable, or in other ways not suitable for production use.
Technology previews are not supported.
Technology previews may only be available for specific hardware architectures.
Details and functionality of technology previews are subject to change. As a result, upgrading to subsequent releases of a technology preview may be impossible and require a fresh installation.
Technology previews can be dropped at any time. For example, if SUSE discovers that a preview does not meet the customer or market needs, or does not prove to comply with enterprise standards. SUSE does not commit to providing a supported version of such technologies in the future.

For an overview of technology previews shipped with your product, see the release notes at https://www.suse.com/releasenotes/.