L in u X ba sics for h acke rs g e t t I n g s t a r t e d w I t h

12
U S I N G A N D A B U S I N G S E R V I C E S
In Linux terminology, a service is an appli-
cation that runs in the background wait-
ing for you to use it. Your Linux system has 
dozens of services preinstalled. Of these, the 
most well known is the ubiquitous Apache Web Server, 
which is used for creating, managing, and deploying 
web servers, but there are so many more. For the pur-
poses of this chapter on services, I have selected just 
four that are of particular importance to the hacker: 
Apache Web Server, OpenSSH, MySQL/MariaDB, 
and PostgreSQL.
In this chapter, you’ll learn how to set up a web server with Apache, 
physically spy with OpenSSH, access data with MySQL/MariaDB, and store 
your hacking information with PostgreSQL

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Chapter 12
Starting, Stopping, and Restarting Services
Before we begin to work with these four crucial services, let’s start by exam-
ining how to start, stop, and restart services in Linux.
Some services can be stopped and started via the GUI in Kali Linux, 
much as you would on an operating system like Windows or Mac. However, 
some services require use of the command line, which we’ll look at here. 
Here is the basic syntax for managing services:
service servicename start|stop|restart
To start the apache2 service (web server or HTTP service), you would 
enter the following:
kali >service apache2 start
To stop the Apache web server, enter:
kali >service apache2 stop
Usually, when you make a configuration change to an application 
or service by altering its plaintext configuration file, you need to restart 
the service to capture the new configuration. Thus, you would enter the 
following:
kali >service apache2 restart
Now that you understand how to start, stop, and restart services from 
the command line, let’s move on to the four most critical Linux services to 
hackers.