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How to Configure a RADIUS Server with NPS on Windows Server 2016 — step-by-step Windows Server 2016 tutorial on Progressive Robot

How to Configure a RADIUS Server with NPS on Windows Server 2016

How to Set Up Windows Server 2016 NPS RADIUS Network Policy Server (NPS) is the Microsoft implementation of a RADIUS (Remote Authentication Dial-In User Service) server and proxy. NPS provides centralized authentication, authorization, and accounting (AAA) for network access requests, including VPN connections, 802.1X wireless and wired authentication, dial-up, and remote access through RRAS. By […]

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How to Install and Configure Postfix Mail Server on RHEL 8 — step-by-step RHEL 8 tutorial on Progressive Robot

How to Install and Configure Postfix Mail Server on RHEL 8

Postfix is a high-performance, security-focused Mail Transfer Agent (MTA) that ships with RHEL 8 and is the default replacement for Sendmail. It handles the delivery of outbound email and, when configured correctly, accepts inbound mail for local users. Understanding Postfix is foundational for any RHEL administrator who needs to send system alerts, application notifications, or […]

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How to Install MariaDB on RHEL 8 — step-by-step RHEL 8 tutorial on Progressive Robot

How to Install MariaDB on RHEL 8

MariaDB is a community-developed, fully open-source relational database management system that was forked from MySQL and remains highly compatible with it. On RHEL 8, MariaDB is conveniently available through the AppStream module system, allowing you to install a specific stream version without adding third-party repositories. This tutorial covers installing MariaDB 10.5 via AppStream, starting and […]

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How to Configure Bacula Backup on FreeBSD 12 — step-by-step FreeBSD 12 tutorial on Progressive Robot

How to Configure Bacula Backup on FreeBSD 12

Introduction How to Configure Bacula Backup on FreeBSD 12 is a core administration task for any FreeBSD 12 server operator. FreeBSD 12 ships with the 15.0-RELEASE kernel, ZFS as the default root filesystem, Capsicum capability sandboxing improvements, and an updated ports tree. Unlike Linux distributions, FreeBSD uses rc(8) for service management, pf for packet filtering, […]

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How to Install Composer on FreeBSD 12 — step-by-step FreeBSD 12 tutorial on Progressive Robot

How to Install Composer on FreeBSD 12

Introduction Deploying install composer on freebsd 12 on a FreeBSD 12 machine differs from Linux in several important ways: packages come from the FreeBSD Ports Collection or the binary pkg repository, services are registered in /etc/rc.conf via sysrc(8), and firewall rules are written in pf.conf(5) syntax. This tutorial stays entirely within the standard base + […]

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Common Problems 118508

Permission denied (publickey) for valid SSH user

🟡 Medium   ⏱ 5–30 min  Last verified: 14 August 2019 📖 ~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 Set Up System Center on Windows Server 2016 — step-by-step Windows Server 2016 tutorial on Progressive Robot

How to Set Up System Center on Windows Server 2016

How to Configure Windows Server 2016 System Center Microsoft System Center is a suite of management products designed to provide unified monitoring, configuration management, data protection, and virtualization management for Windows-based environments. The main components are System Center Operations Manager (SCOM), System Center Configuration Manager (SCCM), System Center Data Protection Manager (DPM), System Center Virtual […]

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How to Set Up Varnish Cache as a Reverse Proxy on RHEL 7 — step-by-step RHEL 7 tutorial on Progressive Robot

How to Set Up Varnish Cache as a Reverse Proxy on RHEL 7

How to Set Up Varnish Cache as a Reverse Proxy on RHEL 7 Varnish Cache is a high-performance HTTP reverse proxy and caching accelerator designed to sit in front of your web server. When a visitor requests a page, Varnish checks whether it holds a fresh cached copy. If it does, the response is served […]

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Common Problems 118417

Ubuntu 16.04 LTS SSH permission denied (publickey)

🟡 Medium   ⏱ 5–30 min  Last verified: 13 August 2019 📖 ~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 Set Up SSL/TLS Certificates on IBM AIX 7.1 — step-by-step IBM AIX 7.1 tutorial on Progressive Robot

How to Set Up SSL/TLS Certificates on IBM AIX 7.1

Introduction IBM AIX 7.1 is the latest release of IBM’s enterprise-grade UNIX operating system, running on IBM Power Systems hardware. Known for its reliability, security, and performance in mission-critical environments, AIX 7.1 introduces enhanced virtualization, security hardening, and cloud integration features. This guide covers how to set up ssl/tls certificates on ibm aix 7.1 on […]

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