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

Integrity Measurement Architecture, digital hashes, and signatures for enhancing security

SELinux, as aforementioned, can increase your system security by confining processes to what is intended for them to do, but in order to improve the protection, you can make use of another feature of the kernel, the integrity subsystem, provided by two components (http://linux-ima.sourceforge.net/):

  • Integrity Measurement Architecture (IMA), which maintains a runtime list of measures
  • Extended Verification Module (EVM), which detects alterations to measurements

The first component, IMA, checks the file contents when opened or executed, stores the obtained values, and allows the validation while permitting tunning via custom policies.

The second component, EVM, hashes the values from IMA, and SELinux attributes via cryptographic functions.

Of course, if the system has support for the Trusted Platform Module (TPM), it can be used to increase the level of hardening of the...