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Complete Guide: Securing a Rocky Linux KVM Host + Fixing Mail Server Dual-NIC Issues

Complete Guide: Securing a Rocky Linux KVM Host + Fixing Mail Server Dual-NIC Issues

Jun 2, 2026 | Advanced Linux Scripting, Learn Linux in practical way

Introduction Running a KVM host with multiple VMs requires careful security configuration. This guide documents real-world challenges including network instability, firewall issues, and a tricky dual-NIC routing problem on a mail server VM. Part 1: Initial Server...
iRedMail Backup & Disaster Recovery: Don’t Learn This the Hard Way

iRedMail Backup & Disaster Recovery: Don’t Learn This the Hard Way

May 25, 2026 | Advanced Linux Scripting, Learn Linux in practical way

Here’s a scenario no server administrator wants to face 🙂 You wake up to find your email server unresponsive. The disk has failed. Your hosting provider says the last backup is from 6 months ago. Your CEO is asking why no one can send or receive email. What do...
Get Instant Server Alerts on Your Phone: Setting Up ntfy.sh with Fail2ban

Get Instant Server Alerts on Your Phone: Setting Up ntfy.sh with Fail2ban

May 25, 2026 | Advanced Linux Scripting, Learn Linux in practical way

Stop checking logs manually. Get instant push notifications when your server is attacked. Free, no registration, works with Fail2ban, Docker, cron jobs, and scripts. Complete setup guide for iOS and Android. You have fail2ban running. Your firewall is configured. Your...
iRedMail Security Hardening From Default to Production-Ready in 10 Minutes

iRedMail Security Hardening From Default to Production-Ready in 10 Minutes

May 25, 2026 | Advanced Linux Scripting, Learn Linux in practical way

Default iRedMail installations work but aren’t secure. Follow this 10-point checklist to harden your mail server: SSL certificates, fail2ban, SASL authentication, firewall, PHP security, real-time alerts, and more. You’ve just installed iRedMail. Webmail...
The Complete iRedMail Upgrade Guide: From 1.7.4 to 1.8.2 on Red Hat, CentOS, Fedora, Rocky Linux 10.1

The Complete iRedMail Upgrade Guide: From 1.7.4 to 1.8.2 on Red Hat, CentOS, Fedora, Rocky Linux 10.1

May 25, 2026 | Advanced Linux Scripting, Learn Linux in practical way

I recently upgraded two production iRedMail servers from version 1.7.4 to 1.8.2. The official documentation is excellent but assumes a perfect world. In reality, you’ll encounter: PHP version mismatches (older OS versions) File permission issues after upgrade...
Step-by-Step Guide: Securing a Rocky Linux 10 KVM Host (SSH + Firewalld + Fail2Ban)

Step-by-Step Guide: Securing a Rocky Linux 10 KVM Host (SSH + Firewalld + Fail2Ban)

May 24, 2026 | Advanced Linux Scripting, Learn Linux in practical way

This guide explains how to securely configure a Rocky Linux 10 KVM virtualization host with proper network segmentation, SSH hardening, and intrusion protection using Fail2Ban and firewalld. Before You Start (IMPORTANT SAFETY RULE) Never apply firewall or SSH...
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News & Updates

  • Fixing the “SASL: Connect to Dovecot Auth Socket Failed” Error
  • Mail Server Hardening – Securing iRedMail Against Modern Attacks
  • Securing Your Red Hat, CentOS, Rocky Linux 10.2 KVM Host Server – A Complete Hardening Guide
  • SELinux: Fix ‘Permission denied’ for swtpm (libvirt TPM Emulator) on Rocky Linux 10
  • Postfix Postscreen Error: How to Fix ‘No such file or directory’ for LMDB Maps

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