How to install Nginx on Ubuntu

  • 28 April 2020
  • ADM

Nginx is one of the most popular web servers in the world. It is also known to be more resource-friendly than Apache in most cases and can be used as a web server or as a reverse proxy.


Install and use firewalld on Ubuntu

  • 11 May 2020
  • ADM

Firewalld is one of the Linux firewall management tool and it is available on the in the Ubuntu's default repositories, therefore it is available to be installed from these repositories using the apt packaging system.


How to check the JDK version of a class file

  • 17 March 2020
  • ADM

When running a Java application it is mandatory that the JRE version to match or to be higher that the JDK version used to compile the application.

You will get the "Unsupported major.minor version 52.0" error when trying to run an Java 1.8 application using a lower version of Java.


XML and HTML sitemap file in SEO

  • 16 February 2020
  • George

The sitemap's a file place on your website that will enable Google and other search engines to crawl better and understand the structure of the site. Sitemaps also tell search engines which pages on your site are most important. It's a binder of your website's content.


How to fix apt lock-frontend error in Ubuntu

  • 24 August 2019
  • ADM

How to fix the E: Could not get lock /var/lib/dpkg/lock-frontend - open (11: Resource temporarily unavailable) error.


How to execute shell command from Java

  • 20 June 2018
  • ADM

How to execute a shell command from Java using Runtime.getRuntime().exec() method.