56 articles
best
Best VPN for Linux in 2025
We tested 8 VPNs on Debian, Arch, and RHEL. Here are the best Linux VPNs for 2025 with real CLI setups, WireGuard configs, and kill switch verification.
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guide
How to Harden Your SSH Server
Step-by-step SSH server hardening for sysadmins: disable root login, enforce key auth, configure AllowUsers, set up Fail2ban, and audit with ssh-audit.
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guide
SSH Key Authentication Setup: Step by Step
Set up SSH key authentication on Linux in 2026. Real commands, Ed25519 keys, authorized_keys hardening, and sshd_config tuning for sysadmins.
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guide
Linux Server Security Checklist 2025
A practical Linux server security checklist for sysadmins: SSH hardening, firewall rules, audit tools, and patch management with real commands.
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comparison
OpenVPN vs WireGuard: Which Should You Use
OpenVPN vs WireGuard compared for sysadmins: speed benchmarks, codebase size, kernel integration, and which protocol wins for specific workloads.
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guide
How to Set Up a VPN Server on Linux
Set up a WireGuard or OpenVPN server on Linux in 2026. Real commands, configs, and hardening steps for sysadmins and DevOps engineers.
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WireGuard Setup on Linux: Step-by-Step Guide
Configure WireGuard VPN on Linux in under 15 minutes. Real commands for Ubuntu, Debian, and RHEL. Covers keys, peers, routing, and persistent tunnels.
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How to Set Up Fail2ban on Linux
Set up Fail2ban on Linux in 2026: real config examples, custom jails, SSH hardening, and tuning tips for sysadmins. Tested on Ubuntu 24.04 and RHEL 9.
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guide
Certbot and Let's Encrypt on Nginx: Full Guide
Install and configure Certbot with Let's Encrypt on Nginx in 2026. Real commands, automation, renewal, wildcard certs, and troubleshooting for sysadmins.
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guide
SSL/TLS Setup on Nginx: Full Guide
Configure SSL/TLS on Nginx with real commands, cipher tuning, OCSP stapling, and A+ ratings. Step-by-step for sysadmins in 2026.
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best
Best Password Manager for Linux CLI in 2025
Top CLI password managers for Linux sysadmins in 2025. Real commands, GPG setup, team sync, and a direct recommendation for DevOps workflows.
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guide
Linux Firewall: iptables Guide for Beginners
Master iptables on Linux: real commands, chain logic, NAT, stateful rules, and persistence. Tested on Debian 12 and RHEL 9. No fluff, just working configs.
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comparison
Kali Linux vs Parrot OS: Which for Pentesting
Kali 2024.4 vs Parrot OS 6.2 compared on tools, RAM use, OPSEC defaults, and real pentesting workflows. Pick the right distro for your engagement.
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guide
How to Audit a Linux Server
Audit a Linux server with real commands: user accounts, open ports, SUID files, cron jobs, kernel params, and log review. Step-by-step for sysadmins.
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guide
Linux iptables Tutorial: Rules and Chains
Master iptables rules and chains on Linux. Real commands, tested configs, and packet flow diagrams for sysadmins managing firewall policy in 2026.
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best
Best VPN for Developers in 2025
NordVPN and four other VPNs tested on Linux CLI, split tunneling, and API access. Real benchmarks for sysadmins and DevOps engineers.
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guide
Linux SSH Tunneling: Port Forwarding Guide
Master SSH local, remote, and dynamic tunneling on Linux. Real commands, sshd configs, and use cases for sysadmins and DevOps engineers.
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SSH Jump Host Guide: ProxyJump Explained
Master SSH ProxyJump and jump hosts for secure bastion access. Real configs, agent forwarding, tunneling, and hardening for sysadmins and DevOps engineers.
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best
Best Linux Security Tools in 2025
The 10 best Linux security tools in 2025, tested by sysadmins: real commands, version numbers, benchmark data, and direct recommendations.
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guide
Two-Factor Authentication on a Linux Server
Set up 2FA on Linux with Google Authenticator PAM or TOTP. Real commands, SSH config, sudo hardening, and tested edge cases for production servers.
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guide
GPG Encryption Tutorial for Linux
GPG encryption on Linux from key generation to automated signing pipelines. Real commands, real configs, tested on GnuPG 2.4.x in 2026.
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guide
Privacy-First AI Applications on Linux
Run AI tools locally on Linux with zero data leakage. Ollama, llama.cpp, and Open WebUI setup with network isolation, auditd, and real config examples.
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Best Linux VPN Server Setup: WireGuard Guide
Set up WireGuard VPN on Linux in under 20 minutes. Real commands, kernel config, peer management, and hardening for sysadmins and DevOps teams.
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guide
Linux Disk Encryption with LUKS
Set up LUKS disk encryption on Linux from scratch. Real commands for cryptsetup 2.x, keyfiles, LUKS2 headers, and automated unlocking in production.
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Let's Encrypt Auto-Renewal: Certbot Cron Guide
Set up Certbot auto-renewal with cron or systemd timers. Real configs, failure alerts, and pre/post hooks tested on Ubuntu 24.04 and Debian 12.
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guide
Linux Port Scanning with nmap: Practical Guide
Master nmap port scanning on Linux with real commands, scan types, timing, NSE scripts, and firewall evasion techniques used by working sysadmins.
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Linux Privilege Escalation: What Sysadmins Must Know
Real Linux privilege escalation techniques, detection methods, and hardening steps for sysadmins. Commands, configs, and specific mitigations included.
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Linux Log Management: Finding and Reading Logs
Find, read, and analyze Linux logs with real commands. Covers journald, rsyslog, logrotate, and grep patterns for sysadmins and DevOps engineers.
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guide
Intrusion Detection on Linux: Practical Setup
Set up real intrusion detection on Linux with AIDE, Suricata, and auditd. Practical commands, configs, and alert tuning for sysadmins in 2026.
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comparison
AppArmor vs SELinux: Which MAC System to Use
AppArmor vs SELinux compared on policy complexity, distro support, container security, and real-world enforcement. We tested both on Ubuntu 24.04 and RHEL 9.
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comparison
Linux Firewall Comparison: iptables vs nftables vs ufw
iptables, nftables, or ufw: we tested all three on Ubuntu 24.04 and RHEL 9. Here is which firewall tool fits your workload and why.
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guide
Linux tcpdump Guide: Packet Capture Basics
Master tcpdump on Linux with real commands, BPF filters, capture rotation, and TLS inspection. Practical examples for sysadmins and DevOps engineers.
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best
Best Linux Security Distros in 2025
The 7 best Linux security distros for pentesting, forensics, and hardened ops in 2025. Real commands, real configs, tested on bare metal and VMs.
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best
Best Linux Security Audit Tools in 2025
The 8 best Linux security audit tools tested by sysadmins: Lynis, OpenSCAP, Trivy, Falco, and more. Real commands, real output, direct recommendations.
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guide
Fail2ban Advanced Configuration Guide
Go beyond default Fail2ban setup: custom jails, regex filters, multi-port bans, recidive jail, and action scripts tested on Ubuntu 24.04 and RHEL 9.
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Linux SELinux Basics: Getting Started
Learn SELinux fundamentals fast: modes, contexts, policies, and real commands tested on RHEL 9 and Rocky Linux 9. No hand-holding, just working examples.
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Linux CVE Patching: Keeping Your Server Secure
Practical Linux CVE patching guide for sysadmins: scan, prioritize, and apply security patches with real commands, automation tips, and rollback strategies.
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Linux Cryptography Tools: openssl Guide
Master openssl on Linux in 2026: key generation, TLS inspection, certificate signing, benchmarking, and real-world sysadmin workflows with exact commands.
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Linux Logging: syslog and rsyslog Guide
Configure rsyslog 8.x on Linux for centralized logging, TLS transport, log filtering, and rotation. Real commands, real configs, tested on RHEL 9 and Debian 12.
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guide
Linux Password Security: PAM and Shadow Guide
Configure PAM and /etc/shadow correctly on Linux. Real commands for password aging, complexity rules, and hashing algorithms for sysadmins.
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Linux iptables NAT: Network Address Translation
Configure iptables NAT on Linux with real commands for MASQUERADE, DNAT, SNAT, port forwarding, and hairpin NAT. Tested on kernel 6.x.
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guide
Linux Rootkit Detection: chkrootkit and rkhunter
Run chkrootkit and rkhunter correctly on Linux servers in 2026. Real commands, false positive handling, cron automation, and side-by-side tool comparison.
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Linux Zero Trust Security: Practical Guide
Implement zero trust on Linux in 2026: real commands for mTLS, BPF policies, service mesh, network segmentation, and identity-based access control.
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SSH Certificate Authority: Enterprise SSH at Scale
Set up an SSH Certificate Authority to replace authorized_keys across hundreds of servers. Real commands, host and user certs, revocation, and production patterns.
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comparison
OSSEC vs Wazuh: Which HIDS to Choose
OSSEC vs Wazuh compared on architecture, rules, scalability, and ops cost. Real configs, benchmarks, and a direct recommendation for sysadmins.
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guide
Snort IDS Setup on Linux
Install and configure Snort 3 IDS on Linux in 2026. Real commands, rule tuning, pflog integration, and performance benchmarks from our test server.
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Linux TCP Tuning for Security and Performance
Harden and accelerate Linux TCP with real sysctl values, BBR congestion control, SYN flood defense, and TIME_WAIT fixes tested on kernel 6.x.
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guide
Linux AppArmor Profiles: Writing Your Own
Write custom AppArmor profiles for any Linux daemon or app. Real syntax, aa-genprof workflow, deny rules, and enforcement testing covered step by step.
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guide
Linux Intrusion Prevention: Beyond fail2ban
fail2ban is not enough. We tested 6 IPS tools on Linux in 2026: Suricata, CrowdSec, OSSEC, eBPF hooks, and kernel-level hardening with real configs.
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guide
Linux Memory Leak Detection: valgrind Guide
Detect memory leaks on Linux using Valgrind 3.23. Real commands, suppression files, CI integration, and specific fixes for common C/C++ leak patterns.
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Linux Audit Framework: auditd Guide
Master auditd on Linux: install, configure rules, parse logs, and automate compliance reporting. Real commands and configs for sysadmins.
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Linux Security Modules: LSM Overview
How LSM works in Linux 6.x, when to use SELinux vs AppArmor vs Smack, real commands for auditing and stacking modules on production systems.
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Linux seccomp: Restricting System Calls
Harden Linux processes with seccomp filters. Real examples for Docker, systemd, and custom BPF profiles. Cut your attack surface to under 50 syscalls.
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guide
Linux Hardened Kernel: grsecurity and Hardening
Apply grsecurity, PaX, and upstream hardening patches to your Linux kernel. Real configs, sysctl tuning, and build steps for production sysadmins.
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Linux Memory Forensics: Incident Response
Capture and analyze live Linux memory during incident response. Real commands, Volatility 3, LiME, and triage workflows tested on Ubuntu 24.04 and RHEL 9.
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guide
Nikto Web Scanner on Linux: Usage Guide
Run Nikto 2.x on Linux to find web vulnerabilities fast. Real commands, tuning flags, output formats, and CI/CD integration covered.
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