HTTPS is no longer optional — browsers mark HTTP sites as “Not Secure”, search engines penalise them in rankings, and many modern browser APIs (service workers, geolocation, camera access) require a secure context. Let’s Encrypt provides free, automated, and trusted SSL/TLS certificates via the ACME protocol, and Certbot is the recommended ACME client that handles […]
Apache virtual hosts are the mechanism by which a single Apache HTTP Server instance serves multiple websites, distinguishing between them using the ServerName directive and the incoming Host HTTP header. Name-based virtual hosting (the most common type) allows hundreds of domains to share a single IP address, with Apache routing each request to the correct […]
Apache HTTP Server (httpd) is the most historically significant web server in the history of the internet, powering billions of websites since 1995. On RHEL 9, Apache is available as httpd from the AppStream repository and integrates with SELinux, firewalld, and systemd. Apache’s module architecture makes it highly extensible: mod_rewrite for URL manipulation, mod_ssl for […]
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 […]
Network configuration on RHEL 9 is managed by NetworkManager, and the primary tools for working with it are nmcli (NetworkManager Command-Line Interface) and the traditional ip command from the iproute2 package. Understanding both is essential: nmcli creates persistent network profiles that survive reboots and are managed by NetworkManager, while the ip command makes temporary changes […]
rsync is the Swiss Army knife of file synchronisation for Linux administrators. Unlike scp, which blindly copies every file every time, rsync computes a rolling checksum to identify changed file blocks and transfers only what has changed — making subsequent syncs dramatically faster and less bandwidth-intensive. It preserves file attributes (permissions, ownership, timestamps, ACLs, extended […]
DNS resolution on a Linux server is a multi-layered system. When an application calls getaddrinfo(“example.com”), the request passes through the Name Service Switch (NSS) framework, which consults sources in the order defined in /etc/nsswitch.conf — typically /etc/hosts first, then a DNS resolver. The DNS resolver reads its configuration from /etc/resolv.conf, which lists the DNS servers […]
Red Hat Enterprise Linux 9 (RHEL 9, codenamed “Plow”) is the most significant release of RHEL in years, built on Linux kernel 5.14, OpenSSL 3.0, and shipped with a hardened-by-default security posture including SELinux enforcing mode, nftables as the default firewall backend, and full support for the latest POWER, ARM, and x86_64 architectures. Whether you […]
User account management is one of the most fundamental administrative tasks on any Linux server. On Red Hat Enterprise Linux 9, every process, file, and network socket is owned by a user and group, making correct account hygiene essential for both security and auditability. Understanding the full lifecycle — creation, modification, and removal — and […]
Red Hat Enterprise Linux 9 uses firewalld as its default firewall management daemon, backed by nftables as the kernel netfilter framework (replacing iptables which was the default in RHEL 7 and earlier). firewalld provides a zone-based model where each network interface is assigned to a trust zone — public, internal, dmz, trusted, and more — […]
Progressive Robot: Your Gateway to Comprehensive IT Solutions — Specializing in Web Development, Mobile App Development, and Expert IT Services.
© All Copyright by Progressiverobot.com
VAT Number ( 506152326 )
