Author: Rahul

I, Rahul Kumar am the founder and chief editor of TecAdmin.net. I am a Red Hat Certified Engineer (RHCE) and working as an IT professional since 2009..

Maven is a powerful project management tool that streamlines the build process for Java projects. It manages project builds, dependencies, and documentation from a central piece of information. If you’re new to Maven, this guide will help you set up your first Java project using Maven. Follow these steps to get started. Prerequisites Before you begin, ensure you have the following installed on your system: JDK (Java Development Kit) 1.8 or above Apache Maven 3.6.3 or newer You can verify the installations by running java -version and mvn -version in your terminal or command prompt. Step 1: Generate Project Structure…

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Kubernetes has become the go-to solution for container orchestration, allowing developers to deploy, manage, and scale containerized applications with ease. However, setting up a Kubernetes cluster can be a complex process, involving numerous steps and configurations. This is where Ansible, an open-source automation tool, comes into play. By automating the deployment process, Ansible can significantly simplify the creation of a Kubernetes cluster. In this guide, we’ll walk you through the process of building a Kubernetes cluster using Ansible. We assumes that all nodes in K8s cluster is running with Ubuntu Linux operating system. Prerequisites Before we dive into the setup…

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In today’s IT infrastructure, ensuring that servers operate within their capacity limits is crucial for maintaining system health and performance. One of the key aspects of server management is memory utilization monitoring. High memory usage can lead to slower application response times, system instability, or even crashes. To address this, we introduce an efficient memory monitoring solution: a Bash script designed to trigger threshold alerts, seamlessly integrating with Nagios, a widely used monitoring tool. This script (https://github.com/tecrahul/nagios-plugins/blob/main/check_memory.sh) is a testament to the power of open-source collaboration. Inspired by the work available on our GitHub, this article expands upon the script’s…

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Spring Boot is a powerful framework that simplifies the development of new Spring applications through sensible defaults. One of its many features is the embedded server that comes pre-configured, allowing developers to run applications out of the box. However, there might be situations where the default server port (usually 8080) conflicts with other applications or does not meet specific deployment requirements. This guide will walk you through the process of changing the default port in a Spring Boot application, ensuring your application runs smoothly on your desired port. Spring Boot’s Default Port Before diving into the customization, it’s essential to…

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In terms of IT automation, Ansible stands out for its simplicity, versatility, and powerful capabilities. As organizations strive for efficiency and seamless IT operations, understanding the architecture of Ansible becomes crucial. This article dives deep into the core components, workflows, and architectural nuances of Ansible, providing a comprehensive guide to its architecture. Introduction to Ansible Ansible is an open-source automation tool that automates software provisioning, configuration management, and application deployment. Developed by Michael DeHaan and acquired by Red Hat in 2015, it has grown to become one of the most popular automation tools, thanks to its agentless architecture, simplicity in…

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Before delving into the specifics of Docker Compose, it’s essential to understand what Docker volumes are and why they are necessary. Volumes are a mechanism to persist and share data between containers and between container and host. Unlike the ephemeral nature of containers, which lose all their data when they are stopped or deleted, volumes are designed to persist data independently of the container’s lifecycle. This is crucial for databases, logs, or any data that needs to survive beyond the life of a container. Why Use Docker Volumes in Docker Compose? Docker Compose simplifies the process of running multi-container Docker…

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In the realm of email communication, the significance of DNS (Domain Name System) records cannot be overstressed. DNS records play a crucial role in ensuring that your emails not only reach their intended recipients without any hitches but also help in safeguarding your domain’s reputation. This comprehensive guide will walk you through the essential DNS records for email services, including how to configure them for optimal email delivery and security. Understanding DNS Records for Email There four key types of DNS records relevant to email services: MX, SPF, DKIM, and DMARC. The MX records direct email to the appropriate mail…

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When working with Maven, a common issue that developers encounter is the error message “Invalid Target Release: 11”. This error typically occurs when Maven is trying to compile Java code targeting a Java version (in this case, Java 11) that is not available or properly configured in the environment. This article will guide you through the steps to resolve this issue effectively. Understanding the Error The “Invalid Target Release: 11” error means that Maven is instructed to compile the code with Java 11, but it cannot find the appropriate Java Development Kit (JDK) version. This discrepancy can arise due to…

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In the realm of web development, managing date and time is a common but crucial task. JavaScript, being the backbone of web development, offers various ways to handle date and time formatting, albeit with its own set of challenges. This comprehensive guide aims to demystify the intricacies of date and time formatting in JavaScript, providing developers with the knowledge and tools they need to manipulate these values effectively. Understanding Date Objects in JavaScript JavaScript’s Date object is the starting point for all date and time-related operations. To work with dates and times, you first need to create a Date object,…

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The Java Virtual Machine (JVM) is the cornerstone of Java’s platform-independent capabilities, allowing Java applications to run seamlessly across different operating systems without modification. Understanding the architecture of the JVM is crucial for developers to optimize application performance and leverage the full power of Java. This article provides an insider’s guide to the intricate workings of JVM architecture, shedding light on its components, functionalities, and how it executes Java programs. The Heart of Java’s Cross-Platform Ability At its core, the JVM is an abstract computing machine with its own instruction set. It operates on binary class files containing Java bytecode,…

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