rhel – ITFROMZERO – Share tobe shared!

Saving a server at 2 AM: A detailed guide to DNF Package Manager on RHEL/Rocky Linux

By admin March 19, 2026

At 2 AM, the server reported an error, and DNF was my savior. This article shares practical experience using DNF on RHEL/Rocky Linux, from basic commands to advanced tips, helping you confidently troubleshoot issues.

Virtualization

QEMU/KVM Installation and Configuration Guide on CentOS/RHEL: Optimizing Virtualization Performance

By admin March 13, 2026

KVM/QEMU on CentOS/RHEL is a high-performance virtualization solution, ideal for servers and homelabs. This article provides a detailed guide to installation, configuration, and performance optimization, sharing practical experience to help you master this platform from A to Z.

Centos

Migrating from CentOS 8 to AlmaLinux 9: Comparing 3 Methods with Step-by-Step Instructions

By admin March 7, 2026

A step-by-step guide to migrating your server from CentOS 8 to AlmaLinux 9 using a safe 2-step process: convert to AlmaLinux 8 with the official script, then upgrade to AlmaLinux 9 with ELevate. Compares all 3 migration methods, analyzes trade-offs, and provides a complete post-migration checklist.

Centos

Managing Services with firewalld on CentOS/RHEL: A Practical Guide

By admin March 6, 2026

firewalld is the default firewall management tool on CentOS/RHEL, offering flexible zone-based policies that are easier to manage than plain iptables. This article covers practical usage from quick start to rich rules, port forwarding, and tips drawn from real production server management.

Centos

Configuring SELinux on Rocky Linux: Don’t Disable It Before You Understand What It Does

By admin March 6, 2026

From firsthand experience migrating 5 servers off CentOS 8 EOL to Rocky Linux, this guide covers how to configure SELinux properly — from Permissive for debugging to Enforcing on production — with practical audit2allow, sealert, and semanage examples.

Centos

Installing and Configuring AlmaLinux as a CentOS Replacement: Real-World Experience

By admin March 2, 2026

A guide to installing AlmaLinux and migrating in-place from CentOS 7/8 to AlmaLinux without rebuilding servers. Compares AlmaLinux vs Rocky Linux vs Oracle Linux from a practical DevOps perspective, with basic post-install security configuration included.