Focused on sharing practical Linux technology content, covering Linux fundamentals, applications, tools, as well as databases, operating systems, network security, and other technical knowledge.
This article explains Oracle database backup and recovery fundamentals, covering failure types, logical vs physical backup, RMAN configuration, level 0/1 incremental backup scripts with cron scheduling, flashback technology, and complete vs incomplete recovery methods.
This article details eight common SQL anti-patterns — including OFFSET pagination, implicit type conversion, correlated subqueries in updates, mixed sorting, EXISTS clauses, blocked condition pushdown, late filtering, and unoptimized intermediate results — with execution plans and rewrites that reduce query times from seconds to milliseconds.
This article compares LVS (Layer 4) and Nginx (Layer 7) load balancers, explaining why LVS achieves higher throughput by only inspecting IP headers while Nginx terminates TCP connections for HTTP-aware routing, health checks, and request retry — at the cost of added latency and configuration complexity.
The article explains that classic FC (Famicom/NES) games like Super Mario Bros. and Contra were programmed in 6502 assembly language because the console's 8-bit MOS 6502 CPU, 2 KB RAM, and 40 KB ROM required low-level hardware control and extreme memory efficiency that high-level languages could not provide.
This article uses 28 diagrams to comprehensively explain TCP, covering network layering, TCP header structure, byte-stream orientation, reliable transmission mechanisms (sliding window, ARQ, acknowledgments), congestion control algorithms (slow start, congestion avoidance, fast retransmit/recovery), three-way handshake and four-way termination, UDP comparison, and practical issues like packet fragmentation, sticky packets, and SYN flood attacks.
This article presents 18 practical shell scripts for common system administration tasks including file consistency checks, log rotation, network traffic monitoring, FTP downloads, user input validation, Nginx 502 error auto-recovery, port scanning, batch file renaming, IP blocking, and IP address validation.
This article introduces 20 Linux command-line tools for network monitoring — such as nethogs, nload, iftop, tcpdump, and ntopng — with installation commands, usage examples, and key features for system administrators across distributions.
This article explains the four Linux kernel I/O schedulers—NOOP, CFQ, Deadline, and Anticipatory—detailing their mechanisms, queue structures, priority models, and optimal use cases for traditional disks versus SSDs, with specific latency thresholds and database workload recommendations.
The article explains how NES games like Contra delivered extensive gameplay within 128KB by using tile-based graphics (2KB VRAM), sound-chip synthesis where music is stored as compact note data, and hardware-specific assembly programming that eliminated engine overhead.
This comprehensive illustrated guide covers the entire Linux network stack from physical layer to application layer, detailing protocols like TCP/IP, routing algorithms, DNS, HTTP, and security mechanisms with diagrams and command references.
