systemd – System and service manager in Linux

  • by

1.0 Introduction

systemd is the newer init system used in most Linux distributions since 2015. The first widely used init system was the System V init process, sysvinit. Ubuntu introduced the Upstart init system with Ubuntu 6.10 in 2006. Ubuntu fully migrated to systemd with Ubuntu 15.04 in 2015.… Read more

Failed to fetch webpage, temporary failure resolving domain

  • by

1.0 Error

While configuring a Linux server, the error Failed to fetch webpage, temporary failure resolving domain was observed.

$ sudo apt-get update
Err:1 ... bionic InRelease
  Temporary failure resolving ...
Err:2 ... bionic-updates InRelease
  Temporary failure resolving ...
Reading package lists...
Read more

Composer Manager: Composer’s install command must be run

  • by

1.0 Error

After updating the Drupal 7 version in a website, the following error was observed in the configuration of the Composer Manager module.

Composer Manager: Composer's install command must be run to generate the autoloader and install the required packages.
Read more

How to execute PHP code in HTML under nginx server

  • by

1.0 Error

PHP code was not getting executed in the index.html file when the concerned website was opened in a browser. nginx server was being used to serve the web pages.

2.0 Solution

2.1 Install php7.0-fpm

$ sudo apt-get install php7.0-fpm
2.2 nginx configuration

Add the following lines to the nginx configuration file, /etc/nginx.confRead more

SSL Certificate expired, site not opening

  • by


A website stopped opening in browser, giving the error that the SSL certificate was either invalid or had expired.


Checking the website with wget,

$ wget
--2018-01-14 16:58:36--
Resolving (, 2001:db8:1221:2341:f03c:f27b:12fa:2123
Connecting to
Read more

How to get the value of Pi in bc calculations

  • by

1.0 π

While using bc for calculations, the value of π is sometimes required. Sure, you might remember it as 3.1416, but it is better to use a higher precision value. And it's quite simple to do that.

First, we need to start bc with the option -l (ell) to use the standard math library.… Read more