Book Image

Red Hat Enterprise Linux 9 Administration - Second Edition

By : Pablo Iranzo Gómez, Pedro Ibáñez Requena, Miguel Pérez Colino, Scott McCarty
2 (2)
Book Image

Red Hat Enterprise Linux 9 Administration - Second Edition

2 (2)
By: Pablo Iranzo Gómez, Pedro Ibáñez Requena, Miguel Pérez Colino, Scott McCarty

Overview of this book

With Red Hat Enterprise Linux 9 becoming the standard for enterprise Linux used from data centers to the cloud, Linux administration skills are in high demand. With this book, you’ll learn how to deploy, access, tweak, and improve enterprise services on any system on any cloud running Red Hat Enterprise Linux 9. Throughout the book, you’ll get to grips with essential tasks such as configuring and maintaining systems, including software installation, updates, and core services. You’ll also understand how to configure the local storage using partitions and logical volumes, as well as assign and deduplicate storage. You’ll learn how to deploy systems while also making them secure and reliable. This book provides a base for users who plan to become full-time Linux system administrators by presenting key command-line concepts and enterprise-level tools, along with essential tools for handling files, directories, command-line environments, and documentation for creating simple shell scripts or running commands. With the help of command line examples and practical tips, you’ll learn by doing and save yourself a lot of time. By the end of the book, you’ll have gained the confidence to manage the filesystem, users, storage, network connectivity, security, and software in RHEL 9 systems on any footprint.
Table of Contents (26 chapters)
1
Part 1 – Systems Administration – Software, User, Network, and Services Management
9
Part 2 – Security with SSH, SELinux, a Firewall, and System Permissions
14
Part 3 – Resource Administration – Storage, Boot Process, Tuning, and Containers
21
Part 4 – Practical Exercises

Understanding Stratis

As a new feature, to manage storage, Stratis was included in RHEL 8 as a technology preview (and is still a preview in RHEL 9). Stratis was created to manage local storage by combining a system service, stratisd, with the well-known tools in LVM (explained in Chapter 13, Flexible Storage Management with LVM) and the XFS filesystem (explained in Chapter 12, Managing Local Storage and Filesystems), which makes it very solid and reliable.

Important Note

The filesystems/pools created with Stratis should always be managed with it, and not with the LVM/XFS tools. In the same way, already-created LVM volumes should not be managed with Stratis.

Stratis combines local disks into pools and then distributes the storage in filesystems, as shown in the following diagram:

Figure 14.1 – Stratis simplified architecture diagram

As can be seen, when compared to LVM, Stratis provides a much simpler and easy-to-understand interface to storage...