Author: Rahul

PHP is an acronym of “Hypertext Preprocessor” is a scripting language widely used for developing web applications. It is the server-side scripting language that is embedded in HTML. Which is used to manage dynamic content, databases, session tracking, even build entire e-commerce websites. PHP 8.0 is the latest stable version available for production use. The debian packages for PHP 8 is available under ppa:ondrej/php PPA for Ubuntu systems. In this tutorial, you will learn the following. Install PHP 8 on Ubuntu Install PHP 8 Extensions Setup PHP 8 with Apache Setup PHP 8 with Nginx Switch between multiple PHP versions…

PuTTy is a user-friendly SSH client for the Windows system. Most of the Linux system users are aware and use to connect remote system running SSH server. It also provides you option to create SSH tunnel to provide access to resource within the trusted internal network. With the help of SSH tunnel you can access resources available on other ports, which is not directly accessible from your system. Once you forwarded your localhost port to the port listening on remote network, you can directly access the the remote service by accessing configured port with localhost. The Tunnel provides you port…

Today, I had installed PHP 7.3 and phpMyAdmin on Ubuntu 18.04 LTS system. I am using MariaDB as database server running on the same instance. When I tried to access data in tables using phpMyAdmin got the following error message on screen. Warning in ./libraries/sql.lib.php#613 count(): Parameter must be an array or an object that implements Countable” Solution: It looks issue is due to older version of phpMyAdmin. The version of phpMyAdmin is older before the release of PHP 7.3 and it not properly compatible with that. In order to resolve, we recommend to upgrade the phpMyAdmin version. But you…

Cron name originates from a Greek word Chronos, which is used for time. It is a daemon for the Linux systems to automate the execution of commands or scripts at a specified time intervals. This tutorial will show you the several options to list all scheduled cron jobs for users on Linux systems. How to List Cron Jobs of Current User The default crontab command works for the current logged in user. You can list all the scheduled cron jobs for the current user, execute: crontab –l Output: All the user cron jobs are generally located under /var/spool/cron/crontabs directory. A…

Recently, I have faced the below issue with a new Sendmail installation on a Linux system. While sending emails to a specific domain like [email protected] are showing the error “stat=User unknown”. The issue was happening for a specific domain only. Sending emails to other domain were working properly. The log file entries are looks like below: Jan 7 08:36:04 tecadmin sendmail[22497]: 1078a4RD022497: from=www-data, size=679, class=0, nrcpts=1, msgid=, relay=www-data@localhost Jan 7 08:36:04 tecadmin sendmail[22497]: 1078a4RD022497: [email protected], ctladdr=www-data (33/33), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=30679, relay=[127.0.0.1] [127.0.0.1], dsn=5.1.1, stat=User unknown Jan 7 08:36:04 tecadmin sendmail[22497]: 1078a4RD022497: 1078a4RE022497: DSN: User unknown Solution: After troubleshooting the…

Gitlab is a web-based DevOps lifecycle management tool developed by GitLab Inc. Similar to the Github, Gitlab is also another popular Git version control system used by large number of users. Gitlab also provides great features like issue tracking, To-Do list, continuous integration and deployment (CI/CD) pipelines for the applications. Gitlab also supports integration with various services. The Community edition of Gitlab is available free for use on development and production environment. It provides large number of features required for small to large scale companies. The enterprise edition provides more features but required a paid license. This tutorial will describe…

We always say, Security first. It should be the first priority to keep your hard work safe from the hackers. This tutorial will take few minutes to secure Gitlab server using Let’s Encrypt SSL certificates. Let’s Encrypt provides free SSL certificates to secure your domains and an easy way to auto updates. This tutorial will help you to secure Gitlab service with Let’s Encrypt SSL certificate with enabling the auto renew feature. If you are going with a fresh installation have a look at below guides. Install and Configure Gitlab on Ubuntu 20.04 Install and Configure Gitlab on CentOS 8…

Gitlab is a web-based DevOps lifecycle management tool developed by GitLab Inc. It provides git version control repository management, issue tracking, a To-Do list, continuous integration, and deployment (CI/CD) pipelines for the applications. Gitlab also supports integration with various services. The Community edition of Gitlab is available free for use in the development and production environment. It provides a large number of features required for small to large-scale companies. The enterprise edition provides more features but required a paid license. This tutorial will help you to install Gitlab on Ubuntu 20.04 LTS Linux system. You are going to install Gitlab…

Netdata is an open source tool designed for the real-time system performance monitoring solution. It collects real-time metrics for system activities like CPU uses, memory uses, bandwidth uses and disk activities etc. And displays the information on web interface with graphical charts. Netdata official team recommend to install netdata monitoring tool using the kickstart script. But this tutorial will help you to install Netdata on Ubuntu using default repositories. This tutorial describe you to how to install Netdata on Ubuntu 20.04 LTS Linux system. Prerequisites Login to your Ubuntu 20.04 LTS Linux system with sudo privileged account. Install Netdata on…

In the vast universe of Linux commands, dig stands out as an essential tool for network administrators, cybersecurity professionals, and IT enthusiasts. The Domain Information Groper, or dig, is a powerful command-line utility used for querying DNS (Domain Name System) servers. It helps in troubleshooting DNS issues and fetching information about domain names, including IP addresses, mail servers, and DNS records. This comprehensive guide aims to equip you with a deep understanding of the dig command, enriched with real-world examples to help you master its usage. Understanding the Basics of dig Before diving into complex queries, let’s start with the…