Book Image

Linux Service Management Made Easy with systemd

4 (1)
Book Image

Linux Service Management Made Easy with systemd

4 (1)

Overview of this book

Linux Service Management Made Easy with systemd will provide you with an in-depth understanding of systemd, so that you can set up your servers securely and efficiently.This is a comprehensive guide for Linux administrators that will help you get the best of systemd, starting with an explanation of the fundamentals of systemd management.You’ll also learn how to edit and create your own systemd units, which will be particularly helpful if you need to create custom services or timers and add features or security to an existing service. Next, you'll find out how to analyze and fix boot-up challenges and set system parameters. An overview of cgroups that'll help you control system resource usage for both processes and users will also be covered, alongside a practical demonstration on how cgroups are structured, spotting the differences between cgroups Version 1 and 2, and how to set resource limits on both. Finally, you'll learn about the systemd way of performing time-keeping, networking, logging, and login management. You'll discover how to configure servers accurately and gather system information to analyze system security and performance. By the end of this Linux book, you’ll be able to efficiently manage all aspects of a server running the systemd init system.
Table of Contents (23 chapters)
1
Section 1: Using systemd
12
Section 2: Understanding cgroups
16
Section 3: Logging, Timekeeping, Networking, and Booting

Understanding resource controllers

There are a few different names for this cgroups feature. I prefer to use the term resource controllers. In other documentation, you may see these resource controllers referred to as either subsystems or just as controllers. All of these terms refer to the same thing, which is the cgroups technology that allows us to control the resource usage of the various running processes. Before we start getting our hands too dirty, let's see what resource controllers we have.

Examining the resource controllers

The best way to see what resource controllers we have is to install some cgroup tools. On the Ubuntu machine, do:

donnie@ubuntu2004:~$ sudo apt install cgroup-tools

On the Alma machine, do:

[donnie@localhost ~]$ sudo dnf install libcgroup-tools

On either machine, we can now use lssubsys to view our active resource controllers, like this:

donnie@ubuntu2004:~$ lssubsys
cpuset
cpu,cpuacct
blkio
memory
devices
freezer
net_cls,net_prio...