Security Archives - Page 2 of 17 - ITFROMZERO

Configuring DNS-over-TLS with systemd-resolved on Linux: Boost Security for DNS Resolution

By IT From Zero October 8, 2026

A guide to configuring DNS-over-TLS and DNSSEC with systemd-resolved on Linux — encrypting DNS queries to block ISP eavesdropping and man-in-the-middle attacks. Includes a 5-minute quick start, DNSSEC configuration, per-link DNS, and debugging tips from real production experience.

Centos

Configuring LUKS and Clevis/Tang on CentOS Stream 9: Automatic Disk Encryption (NBDE)

By IT From Zero October 8, 2026

A guide to configuring Network-Bound Disk Encryption (NBDE) on CentOS Stream 9 using LUKS, Clevis, and Tang server. Servers automatically unlock their disks on boot within the internal network, no manual passphrase needed — ideal for DevOps environments and compliance requirements.

Ubuntu

How to Set Up Two-Factor Authentication (2FA) for SSH on Ubuntu with Google Authenticator

By IT From Zero October 7, 2026

Step-by-step guide to setting up two-factor authentication (2FA) for SSH on Ubuntu with Google Authenticator. Combine SSH keys and TOTP codes for robust server security.

Security

How to Install and Configure Fail2ban on Linux: Hands-On Defense Against SSH and Nginx Brute Force

By IT From Zero October 7, 2026

A step-by-step guide to installing and configuring Fail2ban on Linux to block SSH and Nginx brute-force attacks, with real-world unban tips and incremental ban rules for repeat offenders.

Security

Securing PostgreSQL Server on Linux: Hands-on with pg_hba.conf, pgcrypto, and pgaudit

By IT From Zero October 6, 2026

Protect PostgreSQL on Linux across 3 layers: restrict IPs with pg_hba.conf, encrypt sensitive columns with pgcrypto, and audit logs for SOC2/PCI-DSS with pgaudit.

Database

Securing SQLite Data with SQLCipher: A Comprehensive Encryption Guide for Desktop and Mobile

By IT From Zero October 6, 2026

A comparison of 3 local database security approaches and a comprehensive guide to SQLite encryption using SQLCipher (AES-256), with Python code, key storage tips, and WAL optimization.

Linux

Linux AppArmor Guide: Creating Security Profiles to Sandbox Applications

By IT From Zero October 3, 2026

A hands-on guide to configuring AppArmor on Ubuntu/Debian: writing custom profiles, auditing logs in complain mode, and isolating processes against privilege escalation.

Security

How to Use Kube-bench to Audit Kubernetes Security Against CIS Benchmarks

By IT From Zero October 3, 2026

A hands-on guide to scanning vulnerabilities and hardening Kubernetes cluster security against CIS Benchmarks using Kube-bench based on real-world experience.

Ubuntu

Installing and Configuring CrowdSec on Ubuntu: A Production-Ready Alternative to Fail2ban

By IT From Zero October 3, 2026

A hands-on guide to installing and configuring CrowdSec on Ubuntu Server. Discover why CrowdSec outperforms Fail2ban through community CTI and resource efficiency.

Python

Securing Python Source Code with PyArmor: Effectively Preventing Reverse Engineering and Protecting Intellectual Property

By IT From Zero September 25, 2026

Don't lose your Python source code when delivering projects. Here is a detailed guide on using PyArmor to encrypt code, prevent reverse engineering, and manage licenses effectively.