Author

Raymond Ops

Linux ops automation, cloud-native, Kubernetes, SRE, DevOps, Python, Golang and related tech discussions.

747

Articles

Likes

7.1k

Views

Comments

Latest from Raymond Ops

100 recent articles max

Raymond Ops

Aug 11, 2026 · Databases

How to Diagnose MySQL Slow Queries: From Log Capture to Index Optimization

This guide walks MySQL operators through a complete slow‑query troubleshooting workflow—starting with enabling and analyzing the slow‑query log, using pt‑query‑digest and EXPLAIN to pinpoint index, SQL, schema, configuration or hardware bottlenecks, and then applying concrete optimizations such as proper indexing, cursor pagination, JOIN tuning, and server‑level parameter tweaks.

Buffer PoolEXPLAINIndex Optimization

0 likes · 33 min read

How to Diagnose MySQL Slow Queries: From Log Capture to Index Optimization

Raymond Ops

Aug 11, 2026 · Operations

How to Quickly Identify High‑CPU Processes on a Linux Server with a One‑Minute Command Checklist

This article walks through a systematic, three‑stage method—starting with a 60‑second global scan using uptime, top, vmstat and mpstat, then pinpointing the offending process and thread with pidstat, perf and strace, and finally classifying the root cause to apply the appropriate fix—so you can diagnose and resolve Linux CPU spikes without resorting to blind restarts.

cpulinuxperf

0 likes · 16 min read

How to Quickly Identify High‑CPU Processes on a Linux Server with a One‑Minute Command Checklist

Raymond Ops

Aug 9, 2026 · Operations

How a Full Redis Connection Pool Triggered a Service Outage: Step‑by‑Step Investigation

An online education platform experienced a cascade failure when Redis reached its maxclients limit, causing authentication, session, and cache services to become unavailable; the article details the connection mechanism, root‑cause analysis, rapid mitigation steps, and long‑term best practices for preventing similar outages.

Connection PoolJedisRedis

0 likes · 18 min read

How a Full Redis Connection Pool Triggered a Service Outage: Step‑by‑Step Investigation

Raymond Ops

Aug 9, 2026 · Operations

Disk Full on Linux? Run These 8 Diagnostic Commands First

When a Linux server reports a full disk, the article explains three possible causes—actual space exhaustion, inode depletion, or deleted files still held by processes—and walks through eight essential commands, from df and du to lsof, ncdu, iostat, and journalctl, to diagnose and safely resolve the issue.

Disk Spacedfdu

0 likes · 21 min read

Disk Full on Linux? Run These 8 Diagnostic Commands First

Raymond Ops

Aug 8, 2026 · Operations

Mastering K8s Troubleshooting: Common Production Issues and Essential Commands

This guide walks you through the most frequent Kubernetes production problems—from pod failures like CrashLoopBackOff and ImagePullBackOff to node NotReady states, service DNS errors, storage PVC issues, RBAC permissions, and scheduling conflicts—providing step‑by‑step diagnostic commands, concrete examples, and practical remediation strategies to keep your clusters stable and your services running.

IngressKubernetesNode

0 likes · 51 min read

Mastering K8s Troubleshooting: Common Production Issues and Essential Commands

Raymond Ops

Aug 8, 2026 · Operations

A Complete Walkthrough of Investigating High Server Load in Production

This article narrates a step‑by‑step investigation of a sudden CPU load spike on a 24‑core e‑commerce web server, revealing an I/O bottleneck caused by misconfigured log rotation and excessive debug logging, and outlines the diagnostic commands, root‑cause analysis, immediate remediation, and long‑term fixes.

I/O BottleneckLoad Averagelinux

0 likes · 19 min read

A Complete Walkthrough of Investigating High Server Load in Production

Raymond Ops

Aug 6, 2026 · Databases

Diagnosing and Eliminating MySQL Deadlocks in Production

This article explains how MySQL deadlocks arise, details the four necessary conditions, compares lock types, shows how to enable detailed deadlock logging, query lock metadata, interpret logs, and provides practical code‑level and configuration strategies to prevent and resolve common deadlock scenarios in production environments.

InnoDBMySQLdeadlock

0 likes · 20 min read

Diagnosing and Eliminating MySQL Deadlocks in Production

Raymond Ops

Aug 6, 2026 · Information Security

How to Harden SSH Without Locking Yourself Out

This guide explains why the default SSH configuration is insecure, walks through protocol basics, key generation, server hardening options, step‑by‑step safeguards to avoid being locked out, key‑management best practices, troubleshooting tips, and provides a complete hardening script for Linux systems.

Fail2banSSHhardening

0 likes · 25 min read

How to Harden SSH Without Locking Yourself Out

Raymond Ops

Aug 5, 2026 · Cloud Native

How to Diagnose Kubernetes Node NotReady Issues: A Complete Step‑by‑Step Troubleshooting Guide

This guide walks Kubernetes operators through a systematic, step‑by‑step process for diagnosing nodes stuck in the NotReady state, covering kubelet status reporting, common failure reasons, detailed command‑line checks, root‑cause analysis, remediation steps, verification, and long‑term preventive measures.

KubernetesNotReadycertificate

0 likes · 42 min read

How to Diagnose Kubernetes Node NotReady Issues: A Complete Step‑by‑Step Troubleshooting Guide

Raymond Ops

Aug 4, 2026 · Operations

Uncover Hidden Nginx 502 Bad Gateway Config Pitfalls from Logs

This article explains why 502 Bad Gateway errors are the most frequent Nginx issue, quantifies their impact on business availability, and provides a systematic, log‑driven troubleshooting workflow with concrete configuration examples, health‑check setups, and production‑grade best‑practice recommendations.

502ConfigurationNginx

0 likes · 73 min read

Uncover Hidden Nginx 502 Bad Gateway Config Pitfalls from Logs