sysadmin – Page 2 – ITFROMZERO

Setting Up a PXE Boot Server on Linux: Automated OS Installation Over the Network for Multiple Servers

By admin March 23, 2026

A hands-on guide to deploying a PXE Boot Server on Linux with dnsmasq, TFTP, and NFS for automated OS installation across multiple servers over the network. Covers detailed configuration, boot menus, BIOS/UEFI differences, and a quick health check script for the full stack.

Python

Python and Linux: Useful Sysadmin Scripts for Task Automation

By admin March 22, 2026

How to effectively handle repetitive tasks on Linux? Python is the answer. This article guides you on writing useful Python scripts to automate system administration work, helping you be more efficient and reduce risks.

Centos

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.

Linux

Optimize Linux server performance for production: A detailed guide for beginners

By admin March 17, 2026

This article provides a detailed guide on how to optimize Linux server performance for a production environment. From resource monitoring to fine-tuning CPU, RAM, Disk I/O, and Network, it's aimed at beginners.

Network

Free Online Network Tools for SysAdmins: Subnet Calculator, DNS Lookup, IP Converter

By admin March 15, 2026

Free online network tools I keep bookmarked for emergency troubleshooting: Subnet Calculator for CIDR/overlap, DNS Lookup for propagation checks, IP Converter for cross-platform configs — all run directly in the browser, no installation needed.

Linux

How to Configure sudo and the sudoers File on Linux: Safe Permission Management for Each User

By admin March 15, 2026

A comparison of 3 approaches to granting sudo access on Linux: adding users to the wheel/sudo group, editing /etc/sudoers directly, or using /etc/sudoers.d/. Covers the pros and cons of each approach along with practical configuration guides using visudo, Command Aliases, and NOPASSWD for team-based production environments.

Network

Basic Network Knowledge for SysAdmins: IP, Subnet, Gateway – Indispensable Foundations

By admin March 12, 2026

This article delves into three foundational concepts of computer networking: IP Address, Subnet Mask, and Gateway. You'll understand how they work, why they're crucial for SysAdmins, and how to configure them on Linux, along with practical experiences from a SysAdmin managing office and datacenter networks.

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.

Linux

Securing Your SSH Server: Essential Steps to Prevent Getting Hacked

By admin March 4, 2026

A hands-on guide to SSH server security: comparing 4 common approaches, analyzing their trade-offs, and concrete configuration steps from SSH keys to Fail2ban. Prioritize in the right order to protect your server as effectively as possible.

Linux

Installing and Configuring NTP Server on Linux: Fixing Time Sync Issues in Production

By admin March 2, 2026

A guide to installing chrony and configuring internal NTP server/client on Linux, drawn from real production operations experience. Covers cluster configuration, firewall setup, offset verification, and a basic monitoring script.