Author: Danilo

Logrotate on RHEL 8 is an essential tool for Linux system administrators who need to manage large volumes of log files efficiently. It automates the process of rotating, compressing, removing, and organizing logs to prevent uncontrolled disk usage. Log files generated by system services and applications can grow continuously over time. Using Logrotate, administrators can define rotation policies based on time intervals or file size, ensuring that logging remains available while keeping storage usage under control. In this guide, we will explore how Logrotate works on RHEL 8, understand its configuration structure, create custom rotation rules, perform manual rotations, and…

Rsyslog is the default syslog daemon on RHEL 8 and 9, and understanding its configuration is crucial for any system administrator. To check if the rsyslog is running on your system: Rsyslog Basic Architecture and Components Basic Rsyslog Configuration After editing the configuration files, you can run the following command to test the configuration syntax: After changing the rsyslog configuration, you need to restart the daemon to put in place the new configuration/changes: Filtering & Custom Log Files Let’s provide an example: To capture info-level messages in a separate file: 1- Create /etc/rsyslog.d/info.conf with the following content: Note: The basic…

journald is a component of the systemd suite used in Red Hat Enterprise Linux (RHEL) and other modern Linux distributions. It serves as the system logging service, replacing older logging systems, such as syslog. journald is the systemd journal daemon responsible for collecting and managing log messages from: It stores these logs in a binary format rather than plain text, which allows for more structured and efficient querying. We can check the daemon status by executing the following command: Key Features Interacting with the Journal We can use the journalctl command for querying, filtering, and live-viewing logs. For example: 1-…

Getting Started with TuneD on RHEL 8 demonstrates what the TuneD daemon is and how it can be used to optimize system performance. So, what is the TuneD? TuneD is a service/daemon that monitors your system and optimizes the performance under specific workloads. The core of TuneD are “profiles”, which tune your system for different use cases. TuneD is distributed with many predefined profiles for use cases such as: TuneD is a dynamic and static tuning tool that: On RHEL 8, for instance, the TuneD is already installed and enabled by default: What Is It Used For? TuneD helps system administrators: Common TuneD Profiles A…

Understanding the Process Priorities on RHEL 8 illustrates how the system manages process priorities when a program is executed. On a Linux system, when you run a program or command without explicitly setting its priority, it starts with a default nice value of 0. Regardless of whether we’re using Red Hat Enterprise Linux, this concept applies to the majority of Linux distributions. Understanding the Nice Values The nice value determines the priority of a process in terms of CPU scheduling. Here’s how it works: Based on it, let’s analyze some examples:1- Considering that we have two processes:Process A = -18 priority/nice valueProcess…

Process Management on RHEL 8 shows how to handle processes on Red Hat Enterprise Linux. However, the majority of Linux distributions work in the same way. First and foremost: What is a Process? In whatever Linux flavor, a process is any active (running) instance of a program (A process is a running instance of a launched, executable program). But what is a program? Technically, a program is any executable file stored on your machine. Anytime you run a program, you have created a process. One program can start many processes, so, as a system administrator, you need to know how to manage them…