MCE hardware error cpu 0


1.0 Error


While running Ubuntu 18.04.1 on a laptop, the following errors were observed.

mce: hardware error cpu 0 machine check 0 bank 6 ae0000000040110a
mce: hardware error tsc 0 addr ffb07540 misc 238a0000086
mce: hardware error processor 0:40651 time 1540082330 socket 0 Apic 0 microcode 24
ipmi dmi invalid offset 0

The system would stop in the single user mode.… Read more

Failed to fetch webpage, temporary failure resolving domain

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 ''
Err:3 bionic-backports InRelease
  Temporary failure resolving ''
Err:4 bionic-security InRelease
  Temporary failure resolving ''
Reading package lists...
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How to execute PHP code in HTML under nginx server

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.conf.… Read more

SSL Certificate expired, site not opening


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 (||:443...
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How to get the value of Pi in bc calculations

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