Author: Rahul

Linux is a powerful and versatile operating system that runs on a wide range of devices, from smartphones to supercomputers. As a Linux administrator, monitoring system performance is crucial for maintaining stability, optimizing resources, and detecting potential issues before they become problems. Fortunately, Linux provides a variety of tools for monitoring and managing system performance. In this article, we will explore 15 essential system and performance monitoring tools for Linux administrators. Top Top is a command-line utility that provides real-time information about system processes, CPU usage, memory usage, and other system statistics. It displays a list of running processes, sorted…

A CSR stands for ‘Certificate Signing Request’ is an encrypted block of text ,that is generated on the server where the certificate will be used on. A CSR contains information about to your organization and domain name, locality, and country. It also contains the public key that will be included in your certificate. For creating CSR for wildcard ssl , you must specify you domain name starting with “*.” . for eg: *.tecadmin.net or *.example.com. Follow given steps to Create CSR for WildCard SSL on windows Server 2008. Step 1. Open Internet information Server Start IIS by typing inetmgr in…

When you are running a website or web application, it is essential to maintain the security and integrity of your server. One of the simplest yet most important steps is to hide your Apache and PHP version information from HTTP headers. By default, this information is exposed in HTTP response headers, potentially making your server more vulnerable to attacks. In this article, we will show you how to hide Apache and PHP version information from HTTP headers to improve your server’s security. Step 1: Understanding the Risks of Exposed Versions Exposing version information of Apache and PHP may not seem…

If you’re a Windows user who needs to connect to remote servers via SSH, you’re probably familiar with Putty, one of the most popular SSH clients available for Windows. However, Putty isn’t the only option out there. Many other SSH clients offer more features, better security, and a better user experience. When choosing an SSH client, it’s important to consider factors such as security, ease of use, and advanced features. For example, if you’re a system administrator, you may want an SSH client that includes tools for system administration, such as remote desktop and file transfer. If you’re a power…

Red5 is an open-source media server for live streaming solutions that are written in Java. It provides a powerful platform that supports streaming Video (FLV, F4V, MP4, 3GP), Audio (MP3, F4A, M4A, AAC), and RTMP/RTMPT protocols for maximum flexibility. This article will guide you on how to install Red5 Server on CentOS/RHEL 9/8. Prerequisites A CentOS/RHEL 8 or 9 instance with root privileges. Sufficient storage space for the server software and media files. An installed Java Development Kit (JDK), as Red5 is a Java-based application. Step 1: Update the System First, you should start by updating your system to the…

Cron is a powerful scheduling tool used in Unix-like operating systems for running tasks at predetermined times. It’s invaluable for automating system maintenance and administrative tasks. However, when trying to schedule these tasks, you might encounter the error `-bash: crontab: command not found`. This indicates that the Crontab management utility is not installed on your system. This guide provides a detailed, step-by-step tutorial on how to install and configure Crontab, the interface for managing cron jobs, on CentOS and Red Hat Enterprise Linux (RHEL) systems. Introduction Before diving into the installation process, it’s essential to understand what Crontab is and…

vnStat is a network traffic monitoring tool for Linux systems. It is used to track the network traffic data and display it in a convenient graphical interface. vnStat can be used to track bandwidth usage on a per-interface basis, which makes it an ideal tool for monitoring network traffic on servers, routers, and other network devices. This article provides a comprehensive guide on how to set up vnStat on CentOS and Fedora systems. Prerequisites Before installing vnStat, make sure that your system meets the following requirements: A running CentOS or Fedora system A user with administrative or root privileges Step…

ATRPMS is a 3’rd party rpm repository providing up to date packages for Red Hat based systems. We can used it for directly downloading packages or we can use one of the available package manager tools. Read: Adding EPEL and REMI Yum Repository on CentOS & RedHat 7/6/5 To enable atrpms yum repository first login to system using root access. Now import ATrpms signing key for verifying packages using following command. # rpm –import http://packages.atrpms.net/RPM-GPG-KEY.atrpms Now create repository file with .repo extension under /etc/yum.repos.d/ directory and add following content as per your operating system. On CentOS / RHEL / Scientific…

Many times we faced issues with mirroring setup with authentication, So in this article we are going to configure database mirroring by creating endpoint and required certificates for authenticate and authorization. Follow below steps to setup database mirroring in sql server with 1 Principal server and 1 Mirror server. This article does not include witness server. So if you want automatic failover setup this article would not help you. Read this article for role of witness server Step 1. Setup Endpoint and Certificates With the first step we are going to create endpoint on both server and configure certificates for…

Keepalived is used for IP failover between two servers. It facilities for load balancing and high-availability to Linux-based infrastructures. It works on VRRP ( Virtual Router Redundancy Protocol ) protocol. We have running two load balance servers using HAProxy and now we need to implement VRRP between both servers. This tutorial will help you to configure KeepAlived, Use this tutorial to configure HAProxy on both servers. Network Scenario: 1. LB1 Server: 192.168.10.111 ( eth1 ) 2. LB2 Server: 192.168.10.112 ( eth1 ) 3. Virtual IP: 192.168.10.121 Now we are implementing ip failover setup between LB1 and LB2 servers. Graphical representation…