M01:
Introduction to Operating Systems
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TU1: Installing,
configuring and exploiting a computer system
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ASIX1-DAW1
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Practical Exercise 3: Basic
network configuration
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26-10-2021
|
BASIC NETWORK CONFIGURATION
GENERAL CONDITIONS
1- Deadline: 7-11-2021
2- Send your report attached to an e-mail with the
following specifications:
a) E-mail
address:
cf(at)collados.org or jordi.binefa(at)fje.edu depending who is your
teacher
b)
File Name:
b.1) ASIX1: asix1_surname_name_m01tu01pr03.pdf and
asix1_surname_name_m01tu01pr03.odt
b.2) DAW1: daw1_surname_name_m01tu01pr03.pdf and
daw1_surname_name_m01tu01pr03.odt
c) Subject:
c.1) ASIX1:
asix1_surname_name_m01tu01pr03
c.2) DAW1: daw1_surname_name_m01tu01pr03
3- Make
this report individually.
4- Left, right, top and
bottom margins: 2cm.
5- Character format: a)
Font:Arial, b) Size: 10, c) Questions typeface: Bold, d)
Answers typeface: Regular
DOCUMENTATION
1- Basic
network concepts: https://www.dipolnet.com/what_is_the_ip_address_network_mask_gateway__bib538.htm
2- Private vs Public IP addresses: https://www.avast.com/c-ip-address-public-vs-private#gref
3- MAC (or hardware) address: https://slts.osu.edu/articles/whats-a-mac-address-and-how-do-i-find-it/
4-
Linux ip command examples: https://www.cyberciti.biz/faq/linux-ip-command-examples-usage-syntax/
PRACTICAL EXERCISE
FIRST PART
1.- Explain the meaning of the
following network parameters:
a) MAC (or
hardware) address
a) IP address
b) Gateway/Router
c) Primary
and secondary DNS
d) Interface.
Interface identifiers and types.
e)
Configuration Method: Automatic (DHCP) vs
Manual
2.-
Check and show clearly the following network
parameters of the ethernet interface with Network
Manager:
a) Network Interface
identifier
b) MAC (or hardware)
address of your network card
c) IP address of your
computer
d) IP address of your
Gateway/Router
e) IP addresses of your
primary and secondary DNS
3.- Check
the network configuration
Method of your computer
with Network Manager.
4.-
Check
the list of your system network
interfaces identifiers and types.
Identify clearly the ethernet interface
features and particularly the ethernet
interface identifier.
5.-
Check the MAC (or
hardware) address
of your ethernet interface
with ip command.
6.-
Check the IP address of your computer with ip
command.0
7.- Check the IP address of your
Gateway/Router with ip
command.
8.- Check the IP address of your DNS servers
showing the contents of /etc/resolv.conf.
9.- Test your connectivity to:
a) Your system
b)
The Gateway/Router
c) The primary and
secondary DNS
d) www.google.com and
www.collados.org.
e) Explain the process
for testing your connectivity. How do you know if
you can get connection to a host?!!!!.
10.- Find
out the IP address of www.google.com.
How did you find out this
information?
SECOND PART
1.- Disable the networking system
using Network Manager. Explain the process
for disabling the networking system. Check if you are
able to surf on Internet. What is the state of the
network manager icon?
2.- Enable again your networking system
using Network Manager. Explain the process for
enabling again the networking system. Check if you are
able to surf on Internet. What is the state of the network
manager icon?
3.- Configure
(take screenshots of each step) your
ethernet interface using Network
Manager, with the following
specifications:
a) Configuration
method: Manual
b) IP address: from
192.168.1.40 to
192.168.75 (A different IP for each
student's computer. IP addresses will be
assigned
assigned by the teacher) and netmask /20 (or
255.255.240.0).
c) IP address of your
Router: 192.168.1.10
d) Primary DNS: 80.58.0.33
e) Secondary DNS: 8.8.8.8
4.- Show the network configuration of
the ethernet interface with Network Manager.
5.- Check the network
configuration of the
ethernet interface
with ip and
showing the contents of /etc/resolv.conf.
6.- Check
your
connectivity
to www.google.com.
Have you
experienced
any problem?.
Why?
7.- Configure (take
screenshots of
each
step)
your network interface
using Network Manager
with the Automatic
(DHCP) configuration
method again.
8.-
Check again the
network
configuration
of the
ethernet
interface
with
ip
and
showing the
contents of /etc/resolv.conf.
9.-
Check
your
connectivity
to www.google.com.
Have you
experienced
any problem?.
Why?
THIRD PART
1.- Log in the system as a root user. Install on
your computer the following packages of sotfware: openssh-server,
openssh-client and net-tools. Log out of your root
account and become again a regular user.
2.- Run the following command: systemctl
status ssh. Check if the ssh server has been loaded
and is running on your system.
3.- Check the IP address of your virtual machine with
command ip.
4.- Check connectivity with the virtual machine of a
classmate.
5.- Connect your virtual machine to the virtual machine of
the cIassmate using the ssh client. Follow these steps:
a)
Run the command: ssh username@ip_addres -p 22
where username is the username of the classmate in
his/her virtual computer and ip_address is the ip
address of his/her virtual machine.
b) Answer yes to the question
Are you sure you want to continue connecting (yes/no)?.
c) Password --> Write
your username password
d) Check that you have gained access
to the classmate virtual machine.
6.- Ask to the classmate that he/she gains access to your
virtual computer via ssh.
7.- Open a new terminal. Resize your terminal to full
screen. Log in the
system as a root user. Run the command: netstat
-atupn. Take and screenshot and show clearly:
a) The connection established
from your virtual computer to the classmate virtual computer
b) The connection established
from the classmate virtual computer to
your virtual computer
c) State of your ssh server
8.- Close the connection to the classmate virtual
machine running the command exit or logout.
Ask to your classmate that he/she logs out
from your virtual computer via ssh.
9.-
Check that your connection with the virtual machine has been
closed. Run the
command: netstat -atupn. Take and
screenshot and show clearly that the formerly
established connections do not exist any longer.