5.5. Summary
In this chapter, we learned how to configure Kali Linux. We configured network settings, talked
about users and groups, and discussed how to create and modify user accounts, set passwords,
disable accounts, and manage groups. Finally, we discussed services and explained how to set up
and maintain generic services, specifically SSH, PostgreSQL, and Apache.
Summary Tips:
• In a typical desktop installation, you will have NetworkManager already installed and it can be
controlled and configured through Xfce’s system settings and through the top-right menu.
• You can configure the network from the command line with the
ifup
and
ifdown
tools,
which read their instructions from the
/etc/network/interfaces
configuration file. An
even newer tool, systemd-networkd works with the systemd init system.
123
Chapter 5 — Configuring Kali Linux
• By default, the database of Unix users and groups consists of the textual files
/etc/passwd
(list of users),
/etc/shadow
(encrypted passwords of users),
/etc/group
(list of groups), and
/etc/gshadow
(encrypted passwords of groups).
• You can use the
getent
command to consult the user database and other system databases.
• The
adduser
command asks a few questions before creating the account, but is a straight-
forward way to create a new user account.
• Several commands can be used to modify specific fields in the user database including:
passwd
(change password),
chfn
(change full name and the GECOS, or general informa-
tion field),
chsh
(change login shell),
chage
(change password age), and
passwd -e user
(forces the user to change their password the next time they log in).
• Each user can be a member of one or multiple groups. Several commands can be used to
modify group identity:
newgrp
changes the current group ID,
sg
executes a command using
the supplied alternate group, the setgid bit can be placed on a directory, causing files created
in that directory to automatically belong to the correct group. In addition, the
id
command
displays the current state of a user including a list of their group membership.
• You can manually start SSH with
systemctl start ssh
or permanently enable it with
systemctl enable ssh
.
• PostgreSQL is a database server. It is rarely useful on its own but is used by many other
services to store data.
• A typical Kali Linux installation includes the Apache web server, provided by the apache2
package. Being a network service, it is disabled by default. You can manually start it with
systemctl start apache2
.
• With its default configuration, Apache listens on port 80 (as configured in
/etc/apache2/
ports.conf
), and serves pages from the
/var/www/html/
directory by default (as config-
ured in
/etc/apache2/sites-enabled/000-default.conf
).
Now that we have tackled Linux fundamentals and Kali Linux installation and configuration, let’s
discuss how to troubleshoot Kali and teach you some tools and tricks to get you back up and run-
ning when you run into problems.
124
Kali Linux Revealed
|
