Performance

How to Harden Nginx: Security Headers, TLS 1.3, OCSP Stapling on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Harden Nginx: Security Headers, TLS 1.3, OCSP Stapling on RHEL 9

A default Nginx installation serves content, but many security hardening steps are not enabled by default. Hardening Nginx means configuring HTTP security headers to prevent XSS, clickjacking, and MIME sniffing attacks; enforcing TLS 1.3 and strong cipher suites to eliminate outdated protocol vulnerabilities; enabling OCSP Stapling so clients can verify certificate validity without a round-trip […]

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How to Install and Configure OpenLiteSpeed Web Server on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Install and Configure OpenLiteSpeed Web Server on RHEL 9

OpenLiteSpeed (OLS) is the open-source version of LiteSpeed Web Server — one of the highest-performance HTTP servers available, purpose-built for serving PHP applications. OpenLiteSpeed uses an event-driven architecture similar to Nginx but includes a built-in PHP engine (LSAPI) that processes PHP requests 3–5x faster than PHP-FPM behind Nginx, eliminating the socket overhead of the FastCGI […]

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How to Configure HAProxy for HTTP and TCP Load Balancing on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Configure HAProxy for HTTP and TCP Load Balancing on RHEL 9

HAProxy (High Availability Proxy) is a battle-hardened open-source load balancer and proxy for TCP and HTTP workloads. Where Nginx load balancing is sufficient for simple round-robin HTTP distribution, HAProxy provides a richer feature set: advanced health checks with multiple failure thresholds, ACL-based routing, Layer 4 TCP load balancing for non-HTTP protocols (MySQL, Redis, SMTP), detailed […]

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How to Set Up Varnish Cache as a Reverse Proxy on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Set Up Varnish Cache as a Reverse Proxy on RHEL 9

Varnish Cache is a high-performance HTTP reverse proxy designed specifically for caching. Unlike Nginx FastCGI cache which caches PHP output files on disk, Varnish stores cached objects entirely in RAM and can serve tens of thousands of requests per second from memory. Varnish operates in front of your web server: it listens on port 80 […]

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How to Configure Nginx FastCGI Caching on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Configure Nginx FastCGI Caching on RHEL 9

Nginx FastCGI caching stores the output of PHP-FPM (or any FastCGI backend) responses as files on disk and serves them directly without hitting PHP for subsequent requests. For a WordPress site or PHP application serving the same page to many users, this can reduce PHP execution from 200ms to under 1ms and cut server load […]

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How to Enable Brotli and Gzip Compression in Nginx on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Enable Brotli and Gzip Compression in Nginx on RHEL 9

Text-based HTTP responses — HTML, CSS, JavaScript, JSON, XML, SVG — compress dramatically with standard compression algorithms, often achieving 60–80% size reduction. Nginx supports two compression algorithms: gzip (built-in, universal browser support) and Brotli (via the ngx_brotli dynamic module, 15–20% better compression than gzip for text, supported by all modern browsers). Enabling compression is one […]

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How to Configure Nginx Load Balancing (Round-Robin, Least Conn) on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Configure Nginx Load Balancing (Round-Robin, Least Conn) on RHEL 9

Load balancing distributes incoming requests across multiple backend servers, preventing any single server from becoming a bottleneck and providing horizontal scalability and fault tolerance. Nginx supports four load balancing methods natively: round-robin (the default), least connections, IP hash (session persistence), and weight-based. The upstream block defines the pool of backend servers and their weights, and […]

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How to Enable HTTP/2 with Nginx on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Enable HTTP/2 with Nginx on RHEL 9

HTTP/2 is the second major version of the HTTP protocol, standardised in 2015, and offers significant performance improvements over HTTP/1.1: header compression (HPACK), multiplexing (multiple requests over a single connection), server push, and binary framing. On a typical webpage with dozens of assets (CSS, JavaScript, images, fonts), HTTP/2 multiplexing eliminates the head-of-line blocking that forces […]

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

How to Install Nginx on RHEL 9

Nginx (pronounced “engine-x”) is the most widely deployed web server in the world, powering everything from small personal websites to the largest content delivery networks. On RHEL 9, Nginx is available from the AppStream repository and integrates natively with SELinux, firewalld, and systemd. Its event-driven, non-blocking architecture means a single Nginx worker process can handle […]

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How to Perform a System Security Audit with auditd on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Perform a System Security Audit with auditd on RHEL 9

Security auditing is the practice of recording and reviewing system calls, file accesses, user actions, and configuration changes to detect policy violations, investigate incidents, and demonstrate compliance with standards like PCI DSS, HIPAA, and SOC 2. On RHEL 9, the Linux Audit Framework — provided by the auditd daemon — captures events at the kernel […]

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