Linux ops automation, cloud-native, Kubernetes, SRE, DevOps, Python, Golang and related tech discussions.
A comprehensive practical guide covering grep, sed, and awk for log analysis, detailing real-world usage, performance pitfalls, GNU/BSD differences, production risks, and complete troubleshooting workflows with verified commands for CentOS, Ubuntu, and macOS environments.
A systematic troubleshooting guide for Nginx 502 Bad Gateway errors covering six root-cause areas: upstream process/socket issues, config mismatches, permission blocks, application crashes/timeouts, DNS/TCP upstream problems, and host resource exhaustion — with exact commands, config snippets, and a ready-to-run evidence collection script.
This comprehensive guide covers RocketMQ production operations including cluster deployment with NameServer and Broker configurations, message retry mechanisms with backoff strategies, dead letter queue handling and reprocessing, monitoring with Prometheus alerts, and troubleshooting procedures for common issues like message accumulation, disk full, and broker failures.
A comprehensive guide to Linux network fault diagnosis using tcpdump, netstat, and ss, covering TCP state analysis, packet capture filters, kernel parameter tuning, and real-world case studies for TIME_WAIT, SYN_RECV, CLOSE_WAIT, and latency issues.
A comprehensive, scenario-driven reference covering 30+ categories of Linux operations commands — system info, processes, CPU, memory, network, disk, files, logs, users, services, packages, scheduling, performance analysis, text processing, SSH, troubleshooting workflows, dangerous commands, auditing, and efficiency tips — each with purpose, key parameters, real-world examples, and risk warnings.
This comprehensive guide dissects the Linux logging stack — kernel ring buffer, journald, rsyslog, logrotate, and service logs — with configuration details, command references, and five step-by-step troubleshooting cases covering SSH brute force, disk exhaustion, OOM kills, network packet loss, and systemd service failures.
This article details a real-world incident response and recovery process after an accidental rm -rf deletion on Linux, covering filesystem internals, immediate containment steps, recovery tools like extundelete and debugfs, LVM snapshots, and preventive measures to avoid future data loss.
Comprehensive guide covering Linux time concepts, NTP protocol, chrony vs ntpd, clock source selection, leap second handling, configuration templates for cloud, containers, Kubernetes, and isolated networks, plus verification, monitoring, troubleshooting, compliance automation, and rollback strategies.
This article provides a step-by-step guide to troubleshooting CPU 100% incidents in production, covering Linux CPU metrics, Java GC and thread analysis with jstat/jstack/Arthas, system-level tools like perf and flame graphs, and a detailed case study where MySQL backup-induced replica lag triggered cascading Full GCs and CPU saturation.
This comprehensive guide compares frp, WireGuard, and Tailscale for internal network penetration, detailing deployment steps, configuration examples, troubleshooting tips, real-world latency and bandwidth benchmarks, and scenario-based recommendations to help operations engineers select the optimal solution.
