Linux SysAdmin Archives - ITFROMZERO

How to Configure Virtual Data Optimizer (VDO) on CentOS Stream 9: Optimize Storage with Compression and Deduplication

By IT From Zero October 7, 2026

A detailed guide on configuring LVM-VDO on CentOS Stream 9 for inline compression and deduplication, saving up to 80% disk space on VM and backup servers.

Centos

Rescuing CentOS Stream 9: Using Rescue Mode and Chroot to Fix GRUB Errors

By IT From Zero August 13, 2026

CentOS Stream 9 server won't boot? Don't worry. This guide will help you use Rescue Mode and Chroot to fix GRUB errors and restore your system in just a few steps.

Security

Mastering OpenSSL: From Creating Self-Signed Certs to ‘Lightning-Fast’ TLS Debugging

By IT From Zero July 24, 2026

Learn how to master OpenSSL CLI to create certificates, debug TLS handshake errors, and encrypt data files. Essential practical skills for Linux SysAdmins.