Avoid Locking Yourself Out with iptables: Safe Firewall Rollout Guide
A practical guide to updating iptables safely without blocking your own SSH access, including rollback strategies, allowlists, and production checklists.
Linux
How to Quit Telnet Correctly (and Troubleshoot Sessions)
A practical guide to exiting telnet sessions correctly, using escape mode, and using telnet for TCP troubleshooting in modern Linux environments.
Iptables More Strict: Building a Least-Privilege Linux Firewall
Design a strict but practical iptables policy with default deny rules, explicit service allowlists, logging, and safe rollout procedures.
Linux Multi IP Setup: Assigning Multiple Addresses Safely
A practical guide to assigning multiple IP addresses on Linux using modern and legacy methods, with safe rollback and SSH lockout prevention tips.
OS I/O Performance: Memory vs Disk Operations Deep Dive
A comprehensive guide to understanding OS I/O performance, memory hierarchy, blocking vs non-blocking I/O, and strategies for high-performance applications.
Thinking About Docker 2: Static Linking, Layers, and Image Efficiency
Understand static vs dynamic linking in container images, how to inspect dependencies with ldd, and how image layers affect storage efficiency.
VirtualBox Host-Only Network Setup (Host <-> VM)
Complete setup guide for VirtualBox Host-Only networking, including IP planning, static addressing, internet access with dual adapters, and troubleshooting.
构建自己的 Linux 内核模块：从编译到排障
完整讲解 Linux 内核模块的最小示例、编译流程、加载卸载、日志排障和生产环境实践。
eBPF Observability Architecture: Next-Generation System Monitoring
A comprehensive guide to eBPF-based observability architecture, covering eBPF fundamentals, implementation patterns, and building modern monitoring solutions for cloud-native applications.
Linux IPVS: Kernel-Level Load Balancing 2026
Complete guide to IPVS (IP Virtual Server) for high-performance Layer 4 load balancing in Linux
Syslog Protocol: Centralized Logging Setup and Configuration
A practical guide to syslog — message format, rsyslog configuration, TLS transport, forwarding from systemd/journald, and integrating with modern log stacks.
OpenVPN: Complete Setup Guide with Modern Security Configuration
Complete OpenVPN setup guide — server installation, PKI with easy-rsa, client configs, modern cipher suite, two-factor auth, and performance tuning.
Tcpdump Advanced Usage: Command-Line Packet Analysis Mastery 2026
Master tcpdump for professional network analysis. Learn advanced capture techniques, BPF filters, scripting, performance optimization, and production debugging.
WireGuard VPN: Complete Setup Guideor Server and Clients
Complete WireGuard VPN setup guide — server installation, client configuration, routing, DNS, multi-peer management, and troubleshooting.
Linux System Monitoring Complete Guide 2026
Complete guide to Linux system monitoring. Learn about top, htop, sar, prometheus, grafana, and monitoring server performance.
AppArmor Basics: Profile-Based Access Control for Linux
Learn AppArmor fundamentals - profile-based mandatory access control that secures Linux systems through application confinement and fine-grained permissions.
Arch Linux: The Do-It-Yourself Linux Distribution
Master Arch Linux - rolling release, pacman package manager, AUR, system administration, and building custom installations from scratch.
BPF and eBPF: Extended Berkeley Packet Filter Programming
Master BPF and eBPF - write efficient kernel programs for networking, observability, security, and performance analysis on Linux systems in 2026.
Btrfs Deep Dive: Copy-on-Write, Snapshots, and Modern Storage
Comprehensive guide to Btrfs filesystem covering copy-on-write, snapshots, subvolumes, RAID, compression, and data integrity features for 2026.
DNS and DHCP: Network Configuration Services
Master DNS and DHCP on Linux - configure Bind, dnsmasq, DNS resolution, DHCP servers, and network configuration for robust infrastructure.
ext4 and XFS: Enterprise Linux File Systems
Master ext4 and XFS - the dominant enterprise file systems on Linux. Learn features, performance tuning, administration, and when to choose each.
Fedora Server: Enterprise Linux with Cutting-Edge Features
Master Fedora Server - RPM package management, DNF, SELinux, container tools, Cockpit management, and enterprise features for modern infrastructure.
iptables and nftables: Linux Firewall Mastery
Master Linux firewalls with iptables and nftables - comprehensive guide to packet filtering, NAT, and network security for 2026.
KVM Virtualization: Kernel-Based Virtual Machine Mastery
Master KVM virtualization on Linux - hypervisor setup, VM creation, storage, networking, and advanced management with libvirt and virsh.
Linux Boot Process: From Power On to Login Prompt
Comprehensive guide to the Linux boot process covering BIOS/UEFI, bootloaders (GRUB, systemd-boot), kernel initialization, initramfs, and systemd. Master troubleshooting and optimization.
Linux Networking Stack: Architecture, TCP/IP, and Network Interfaces
Comprehensive guide to Linux networking stack covering protocol layers, network interfaces, routing, packet flow, and network performance optimization.
Linux Performance Tuning: sysctl, Kernel Parameters, and System Optimization
Comprehensive guide to Linux performance tuning covering sysctl parameters, kernel optimization, memory management, network tuning, and filesystem performance.
Linux Security Hardening: A Comprehensive Guide
Master Linux security hardening with sysctl tuning, firewall configuration, secure defaults, and production best practices for 2026.
LXC/LXD Containers: Linux System Containers
Comprehensive guide to LXC and LXD covering system containers, container management, networking, storage, and use cases for Linux containers.
RancherOS and MicroOS: Lightweight Container Operating Systems
Explore lightweight container OS - RancherOS history, MicroOS, immutable infrastructure, and running containers directly on metal for modern infrastructure.
strace and Performance Profiling: Linux System Analysis
Master Linux performance profiling with strace, perf, and system analysis tools - diagnose issues, optimize applications, and understand system behavior.
systemd Deep Dive: Linux Service Management
Master systemd including units, services, targets, journald, systemctl commands, and troubleshooting for modern Linux administration.
ZFS on Linux: Enterprise Storage Deep Dive
Master ZFS on Linux - storage pools, snapshots, data integrity, RAID, compression, and advanced features for robust enterprise storage in 2026.
Linux Distributions 2026 Complete Guide: From Desktop to Server
Comprehensive guide to Linux distributions in 2026. Explore Ubuntu, Fedora, Debian, Arch, and specialized distros for desktop, server, and cloud.
WireGuard VPN: Modern, Fast, Secure VPN
Comprehensive guide to WireGuard - the modern VPN protocol. Learn about WireGuard installation, configuration, server setup, client configuration, and network security.
Essential Bash Shell Shortcuts and Productivity Tips
Introduction
Mastering Bash shortcuts transforms the terminal from a place you type slowly into a place you work fast. These shortcuts are built into …
Caddy Server: Complete Static Website Configuration Guide
A complete guide to configuring Caddy server for static websites — HTTPS, compression, logging, caching, redirects, and reverse proxy examples.
Maintaining SSHD
Guide to installing, configuring, and maintaining the OpenSSH server (sshd) on Linux systems.
Open Sout Package Downloads Worldwide
A guide to open source mirror sites worldwide — speed up package downloads for apt, pip, npm, Maven, and more with the right mirror.
Linux Shell命令行快捷键完全指南
学习Linux Shell命令行快捷键，包括如何安全取消命令、编辑命令、快速导航等提高效率的技巧。
Linux LVM (Logical Volume Manager): Complete Guide
Master Linux LVM to flexibly manage disk space. Learn about PV, VG, LV concepts, creation, resizing, snapshots, and production best practices.
strace: Linux System Call Tracer Complete Guide
strace is a powerful Linux command for tracing system calls and signals. Learn to debug, troubleshoot, and analyze program behavior.
Iptables
Iptables router
Iptables Rules Setup CentOS6
CentOS默认防火墙规则解释，CentOS Default Iptables Rules
Shell字符串操作完全指南
深入学习Shell字符串操作，包括获取长度、截取、替换、模式匹配等常用技巧。
The ss Command: Complete Guide to Socket Statistics in Linux
Master the ss command for network socket analysis. Learn to monitor TCP/UDP connections, filter socket states, and troubleshoot network issues effectively.
The dig Command: Complete Guide to DNS Queries in Linux
Master the dig command for DNS lookups. Learn query types, tracing, troubleshooting, and advanced DNS diagnostic techniques.
Linux Shell Commands: A Practical Reference
A practical reference for essential Linux shell commands — process management, networking, file operations, text processing, and system monitoring.
Fixing Library Not Found Errors in Linux: Complete Guide
Resolve dynamic library errors in Linux. Learn to identify, fix, and prevent library loading issues including version mismatches and missing dependencies.
The df Command: Complete Guide to Checking Disk Space in Linux
Master the df command in Linux to monitor disk usage, identify storage issues, and manage file systems effectively. Includes practical examples and advanced usage.
How to Install Software on Linux: Pack Source Builds
A complete guide to installing software on Linux — using package managers (apt, dnf, pacman), installing from source, and managing dependencies.
Linux服务器迁移清单完整指南
Linux服务器迁移完整清单，包括数据备份、配置迁移、服务迁移和验证步骤。
wget Command Guide: Downloading Files from the Command Line
A complete wget guide covering single and batch file downloads, recursive mirroring, authentication, rate limiting, and practical shell scripting examples.
SSH Passwordless Login: Key-Based Authentication Setup
A complete guide to setting up SSH key-based authentication — generating keys, copying to remote hosts, managing multiple keys, and security best practices.