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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 Configure Network Interface Settings with nmcli and ip on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Configure Network Interface Settings with nmcli and ip on RHEL 9

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 […]

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How to Manage System Packages with dnf on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Manage System Packages with dnf on RHEL 9

dnf (Dandified YUM) is the default package manager for RHEL 9 and the successor to yum. It handles installing, updating, removing, and querying RPM packages from local and remote repositories, resolving dependencies automatically using the libsolv library, and supporting transactions that can be rolled back if something goes wrong. For Red Hat Enterprise Linux, packages […]

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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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How to Install and Configure vim and nano on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Install and Configure vim and nano on RHEL 9

Every Linux administrator needs at least one terminal text editor in their toolkit. When a remote server is accessible only via SSH with no GUI, when a configuration file needs editing before a service can start, or when you are recovering a broken system from a rescue shell, your text editor is your primary interface. […]

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How to Use journalctl for Systemd Log Analysis on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Use journalctl for Systemd Log Analysis on RHEL 9

The Linux kernel’s systemd journal is a structured binary log that stores the output of every service, kernel message, boot sequence, and user session. Unlike traditional text-based syslog, the journal stores metadata alongside each log entry — the unit name, PID, UID, executable path, systemd unit state, and priority level — enabling far more precise […]

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How to Monitor Disk Usage with df, du, lsblk and ncdu on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Monitor Disk Usage with df, du, lsblk and ncdu on RHEL 9

Running out of disk space is one of the most disruptive failures a server can experience. When a filesystem fills up, applications crash, log files stop writing (losing audit trails), databases corrupt transactions, and web servers return 500 errors. Proactive disk monitoring is essential — and RHEL 9 provides a full set of tools for […]

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How to Schedule Automated Tasks with cron and anacron on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Schedule Automated Tasks with cron and anacron on RHEL 9

Automated task scheduling is the backbone of server maintenance: backups run at 3 AM, log cleanup happens daily, SSL certificates renew before they expire, and databases are vacuumed weekly. On RHEL 9, there are three scheduling mechanisms each suited to different scenarios. cron is the classic daemon that runs jobs on a schedule defined by […]

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How to Use rsync for Efficient File Synchronisation on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Use rsync for Efficient File Synchronisation on RHEL 9

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 […]

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How to Configure /etc/hosts, /etc/resolv.conf and DNS Resolution on RHEL 9 — step-by-step RHEL 9 tutorial on Progressive Robot

How to Configure /etc/hosts, /etc/resolv.conf and DNS Resolution on RHEL 9

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 […]

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