Linux df command line brief examples

df is a Linux command for for reporting file system disk usage on a Linux system. While brewing coffee at home I found the following. How to view disk usage using df command? Simple! Simplest way is just to type df on the command line and you should get the below output: Filesystem     …

Runlevels in Linux simple table

Hola! Each runlevel has a certain number of services stopped or started, giving the user control over the behavior of the machine. Conventionally, seven runlevels exist, numbered from zero to six. While brewing coffee at home I found the difference between runlevels in Linux. See below. Runlevel Mode Definition 0 Halt Shuts down the system. …

Default Apache virtual host file in Ubuntu

I was asked the other day ‘How does the default Apache virtual host file looks like?’ I was having my Peruvian coffee and decided to place below the default Apache virtual host file in this post for any future reference. <VirtualHost *:80> ServerName www.example.com ServerAdmin webmaster@localhost DocumentRoot /var/www/html ErrorLog ${APACHE_LOG_DIR}/error.log CustomLog ${APACHE_LOG_DIR}/access.log combined </VirtualHost> Super …

Linux File Systems ext2, ext3 and ext4

While having coffee at home I decided to put this table together regarding Linux File Systems and their differences. Let me know if I’m missing something. Ext2 Ext3 Ext4 Stands for Second Extended file system. Stands for Third Extended file system. Stands for Fourth Extended file system. Introduced in 1993. Introduced in 2001. Introduced in …

API requests types brief explanation

API is an Application Programming Interface which is a way that allows communication between two applications using a set of rules. While having a great coffee from Bolivia I found the following API requests types. The main Web Service APIs are: SOAP (Simple Object Access Protocol) uses XML to transfer sets of information in the …

Difference between Inner Join and Outer Join in SQL

An inner join it is the most common kind of join, so common that SQL doesn’t actually make us say “inner join” to do one. An outer join returns a set of records or rows that include what an inner join would return, but also includes other rows for which no corresponding match is found in the …

Activate File Sharing via Terminal macOS

The other day I only had access to my secondary Mac (mac mini) via the Terminal. For some reason Screen Share did not work. I needed to enabled File Sharing on my mac mini in order to transfer some backup files from my MacBook Pro to the mac mini. Coffee was brewing! This is how …

How to Change Root Password in Ubuntu Linux

The root user is disabled by default in Ubuntu. This does not mean the account was removed. After researching while having amazing coffee from Latin America I found the following… If for some reason, you need to enable the root account, all you need to do is to set a password for the root user. In …

What is a session in Google Analytics?

A session is defined as a group of interactions one user takes within a given time frame on your website. For example a single session can contain multiple page views, events, social interactions, and E-Commerce transactions. A single user can open multiple sessions. Those sessions can occur on the same day, or over several days, …