RHEL 9

How to Install Symfony 7 on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Install Symfony 7 on RHEL 9

Symfony is a mature, enterprise-grade PHP framework built on reusable, decoupled components. Unlike Laravel’s all-in-one approach, Symfony emphasises architectural flexibility — many of its components (HttpFoundation, Console, Validator, Security, DependencyInjection) are used independently by other frameworks including Laravel itself. Symfony’s Dependency Injection Container, event dispatcher, and strict coding standards make it the preferred framework for […]

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Common Problems 114565

RHEL 9: Swap Not Activated at Boot

🟡 Medium   ⏱ 5–30 min  Last verified: 12 December 2022 📖 ~1 min read Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches Verification & Acceptance Criteria Rollback Plan Prevention & Hardening Related Errors & Cross-Refs References & Further […]

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How to Install Kubernetes with kubeadm on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Install Kubernetes with kubeadm on RHEL 9

Kubernetes is the industry-standard container orchestration platform for automating deployment, scaling, and management of containerised applications across clusters of servers. While Kubernetes is typically set up using managed services (EKS, GKE, AKS) in cloud environments, installing it with kubeadm on bare-metal or on-premises servers provides full control over the cluster configuration. kubeadm is the official […]

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Common Problems 114501

Kernel Module Missing After Minor Release Update

🟡 Medium   ⏱ 5–30 min  Last verified: 9 December 2022 📖 ~1 min read Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches Verification & Acceptance Criteria Rollback Plan Prevention & Hardening Related Errors & Cross-Refs References & Further […]

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How to Harden Web Servers with Security Headers, CSP, and HSTS on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Harden Web Servers with Security Headers, CSP, and HSTS on RHEL 9

HTTP security headers are a lightweight but highly effective layer of defence for web applications, instructing browsers to enforce policies that mitigate common attacks like clickjacking, MIME-type sniffing, cross-site scripting (XSS), and protocol downgrade attacks. HSTS (HTTP Strict Transport Security) forces browsers to use HTTPS exclusively, while a Content Security Policy (CSP) controls which resources […]

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How to Configure Huge Pages for Database Performance on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Configure Huge Pages for Database Performance on RHEL 9

Standard Linux memory pages are 4 KB, and the kernel must maintain a Translation Lookaside Buffer (TLB) entry for each mapped page. Database systems that manage large shared memory segments — such as PostgreSQL’s shared_buffers, Oracle’s SGA, or MySQL’s InnoDB buffer pool — can create millions of TLB entries, causing frequent TLB misses that significantly […]

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How to Install Python 3 and pip on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Install Python 3 and pip on RHEL 9

Python 3 is the most widely used language for web development, data science, machine learning, automation, and DevOps tooling. RHEL 9 ships with Python 3.9 by default, but newer versions (3.11, 3.12) are available from the AppStream repository and provide significant performance improvements — CPython 3.11 is 10–60% faster than 3.10 for most workloads. The […]

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How to Build and Deploy a Go Web Application on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Build and Deploy a Go Web Application on RHEL 9

Go’s standard library includes a production-ready HTTP server with support for HTTP/2, TLS, and concurrent request handling — no external framework is required for simple web applications. For more complex applications, the Gin framework adds routing, middleware, request binding, and response rendering while maintaining excellent performance. Go web applications compile to a single binary, making […]

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Common Problems 114461

Podman Container Fails with Cgroups v2 Misconfiguration

🟡 Medium   ⏱ 5–30 min  Last verified: 23 November 2022 📖 ~1 min read Table of contents Symptom & Impact Environment & Reproduction Root Cause Analysis Quick Triage Step-by-Step Diagnosis Solution – Primary Fix Solution – Alternative Approaches Verification & Acceptance Criteria Rollback Plan Prevention & Hardening Related Errors & Cross-Refs References & Further […]

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How to Build Grafana Dashboards for Linux Server Metrics on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Build Grafana Dashboards for Linux Server Metrics on RHEL 9

Grafana’s dashboard builder lets you turn raw Prometheus metrics into intuitive visualizations — stat panels for at-a-glance health, time series for trends, and bar gauges for comparisons. With Prometheus and Node Exporter already collecting Linux host metrics, you have everything needed to build a production-grade server dashboard. This tutorial walks through creating panels for CPU, […]

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