Book Image

Oracle Linux Cookbook

By : Erik Benner, Erik B. Thomsen, Jonathan Spindel
Book Image

Oracle Linux Cookbook

By: Erik Benner, Erik B. Thomsen, Jonathan Spindel

Overview of this book

Discover the power of Oracle Linux 8, the free and enterprise-grade Linux distribution designed for use in any environment, with this recipe-style book. Starting with instructions on how to obtain Oracle Linux for both X86 and ARM-based platforms, this book walks you through various installation methods, from running it as a Windows service to installing it on a Raspberry Pi. It unravels advanced topics such as system upgrades using Leapp for major version transitions and using a PXE server and kickstart files for more advanced installations. The book then delves into swapping kernels to take advantage of Oracle’s UEK, exploring boot options, managing software with DNF, and achieving high availability. Detailed recipes involving security topics will assist with tasks such as data encryption, both at rest and in motion. For developers, it offers guidance on building RPM files, using Docker and Podman in a containerized environment, working with AppStreams, and more. For large-scale deployments, the book introduces Oracle Linux Automation Manager for enterprise-level Ansible utilization, from setting up the Ansible server to basic playbook writing. Finally, you’ll discover strategies for cloud migration. By the end of this book, you’ll possess a comprehensive toolkit that will elevate your skills as a Linux administrator.
Table of Contents (16 chapters)

Removing the RHCK

In this recipe, you will learn how to remove RHCK and its unique package dependencies while keeping all of UEK dependencies. Remember that when installing Oracle Linux, the installer automatically installs the Oracle UEK as the default kernel, but you can install RHCK for compatibility purposes.

Getting ready

Old versions of Oracle Linux required a special tool called the kernel-transition package to manage dependencies. With new versions of Oracle Linux, a much easier process is available. For example, with Oracle Linux 8, this requirement is obsolete. All packages are purposely built to avoid any dependencies with regard to the system running on a UEK or RHCK. This makes it significantly easier to remove the UEK or RHCK from the system.

How to do it…

Let’s see how to remove RHCK from our system:

  1. First, let’s check all kernels running within our system by using the grubby command:
Figure 3.19 – Checking the kernels

Figure 3.19...