This wiki page allows you to record the results of your network configuration exercise. You may need to refer to the configuration handout to complete this document.

Answer all questions based on the host that you are configuring in the lab. Edit this wiki page directly to insert your answers. You will probably find this most convenient to do at the same time as you perform the configuration. Where requested, please include listings of the actual configuration files and command outputs directly in the document. Placeholders have been provided for this purpose. Please follow the formatting hints given in the text.

When the exercise is complete you should sign and submit it in for marking. Deadline for completion is the start of the lab on the last week of this term.

This exercise is worth 20% of the module marks.

Which Linux command gives you information about your computer's name on the network?

Answer (delete as appropriate):

hostname 

Use the command selected in Question 1 to determine your host computer's name? What is the name?

Arche

Which configuration file would you need to edit to change your computer's name on the network?

Your answer (one of):

/etc/hostname

Which linux command gives you information on your host's network settings?

Answer one of:

ifconfig 

Use the command selected in Question 4 to complete the following table:

How many hosts can the sub-net defined by your host's netmask support?

Answer one of:

254 

What class of network is the sub-net to which your host has been assigned?

Answer one of:

Class C 

Answer the following questions about your network configuration. Please copy and paste the contents of the files identified in Questions 8 and 11 to your submission.

In which file is the configuration of your Network Interface Controller (NIC) configured?

Answer one of:

/etc/network/interfaces 

Please include a listing of the file chosen in answer to Question 8:

GNU nano 2.2.2         File: /etc/network/interfaces                          
auto eth0
iface eth0 inet static
  address 192.168.2.5
  network 192.168.2.0
  netmask 255.255.255.0
  gateway 192.168.2.1

What is the IP address of the host which serves as the default gateway for your network?

192.168.2.1

What is the hostname of the gateway interface?

Jupiter

In which file is the symbolic names of the networks, hosts and interfaces available on the network defined?

Answer one of:

/etc/hosts 

Please include a listing of the file chosen in answer to Question 11: 127.0.0.1 localhost.localdomain localhost arche

127.0.1.1 arche

# /etc/hosts – Hosts file for ICCT private network

#

# IP FQDN aliases #

127.0.0.1 localhost.localdomain localhost myhost #

192.168.1.1 solaris.icct.co solaris inet-gateway 1

92.168.1.2 venus.icct.com venus www #

Jupiter cluster #

192.168.1.3 gw-jupiter.icct.com gw-jupiter jupiter-if1

192.168.2.1 jupiter.icct.com jupiter jupiter-if2

192.168.2.2 ganymede.jupiter.icct.com ganymede

192.168.2.3 leda.jupiter.icct.com leda

192.168.2.4 carme.jupiter.icct.com carme

192.168.2.5 arche.jupiter.icct.com arche

#

# Saturn cluster

#

192.168.1.4 gw-saturn.icct.com gw-saturn saturn-if2

192.168.3.1 saturn.icct.com saturn saturn-if2

192.168.3.2 hyperion.saturn.icct.com hyperion

192.168.3.3 mimas.saturn.icct.com mimas

192.168.3.4 dione.saturn.icct.com dione

192.168.3.5 titan.saturn.icct.com titan

192.168.3.8 tethys.saturn.icct.com tethys

#

# Add other hostd/clusters below here

# (we'll use this to add virtual hosts to the web-server in a later

# lab exercise)

# The following lines are desirable for IPv6 capable hosts

::1 localhost ip6-localhost ip6-loopback

fe00::0 ip6-localnet

ff00::0 ip6-mcastprefix

ff02::1 ip6-allnodes

ff02::2 ip6-allrouters

ff02::3 ip6-allhosts

What is the symbolic name of your network's gateway interface?

jupiter.icct.com jupiter jupiter-if2

What is the purpose of the Gateway interface?

These are set up independently to talk to their networks. Before they can perform routing between the two networks, they have to be set up to forward IP packets to one another.

Which linux command shows the routing table for your host?

Route

Run the command identified in Question 14 and reproduce its output here.

Answer

<cli prompt=“$” comment=“#”> icct@arche:/home/marwa$ route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface jupiter-net * 255.255.255.0 U 0 0 0 eth0 169.254.0.0 * 255.255.0.0 U 1000 0 0 eth0 default jupiter.icct.co 0.0.0.0 UG 100 0 0 eth0

</cli>

How many interfaces (NICs) must a router have?

2

Which system feature must be turned on if you want a Linux host to act as a router?

enable forwarding

Which run-time command can be used to make a Ubuntu Linux host act as a router?

sudo sh -c “echo 1 > /proc/sys/net/ipv4/ip_forward”

In which file is the setting defined in Question 17 set if you want a Ubuntu host to be configured as a router at boot-time?

/etc/network/options

Reproduce the contents of the file defined in Question 17 to make a Ubuntu host into a router?

ip_forward=yes

What setting has been added to the network configuration file to define a route to icct-net from your sub-network's cluster-server?

up route add -net 192.168.3.0 netmask 255.255.255.0 gw 192.168.1.4

down route del -net 192.168.3.0 netmask 255.255.255.0 gw 192.168.1.4

The Linux command netstat gives a lot of useful information on your network. In the following 3 questions, reproduce the output of various usages of netstat. You should annotate your results with a brief explanation of what they mean. You may need to print the output and attach to the submission.

Give and explain the output of the command netstat -r. <cli promt=“$” comment=“#”>

Kernel IP routing table Destination Gateway Genmask Flags MSS Window irtt Iface jupiter-net * 255.255.255.0 U 0 0 0 eth0 169.254.0.0 * 255.255.0.0 U 0 0 0 eth0 default jupiter.icct.co 0.0.0.0 UG 0 0 0 eth0 </cli> * the -r flag,displays the kernel routing table in the way we've been doing with route.

Give and explain the output of the command netstat -i.

<cli promt=“$” comment=“#”>

Kernel Interface table Iface MTU Met RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg eth0 1500 0 10757 0 0 0 8727 0 0 0 BMRU lo 16436 0 123 0 0 0 123 0 0 0 LRU </cli>

the -i flag, netstat displays statistics for the network interfaces currently configured.

Give and explain the output of the command netstat -ta.

<cli promt=“$” comment=“#”>

Active Internet connections (servers and established) Proto Recv-Q Send-Q Local Address Foreign Address State tcp 0 0 localhost.localdo:mysql *:* LISTEN tcp 0 0 *:www *:* LISTEN tcp 0 0 *:ssh *:* LISTEN tcp 0 0 localhost.localdoma:ipp *:* LISTEN tcp 1 0 arche.jupiter.icc:54603 174.36.133.240-stat:www CLOSE_WAIT tcp 0 0 arche.jupiter.icc:54601 174.36.133.240-stat:www TIME_WAIT tcp 0 0 arche.jupiter.icc:54604 174.36.133.240-stat:www TIME_WAIT tcp 0 0 arche.jupiter.icc:47815 bru01m01-in-f101.1e:www ESTABLISHED tcp 0 0 arche.jupiter.icc:58495 bru01m01-in-f138.1e:www ESTABLISHED tcp6 0 0 [::]:ssh [::]:* LISTEN tcp6 0 0 localhost:ipp [::]:* LISTEN

</cli>

The options -t show active TCP and Unix socket connections. you provide the -a in addition, sockets that are waiting for a connection are displayed as well. This display will give you a list of all servers that are currently running on your system.

Install, if necessary, the traceroute command then answer the following two questions.

Give the output of traceroute from your host to any host on one of the other ICCT networks.

<cli prompt=“$” comment=“#”> icct@arche:/home/marwa$ traceroute carme traceroute to carme (192.168.2.4), 30 hops max, 60 byte packets 1 carme.jupiter.icct.com (192.168.2.4) 1.911 ms 1.917 ms 1.911 ms </cli>

Give the output of traceroute from your host to www.swan.ac.uk

<cli promt=“$” comment=“#”> icct@arche:~$ traceroute -n www.swan.ac.uk traceroute to www.swan.ac.uk (137.44.1.7), 30 hops max, 60 byte packets 1 192.168.2.1 0.568 ms 0.553 ms 0.541 ms 2 * * * 3 * * * 4 * * * 5 * * * 6 * * * 7 * * * 8 * * * 9 * * * 10 * * * 11 * * * 12 * * * 13 * * * 14 * * * 15 * * * 16 * * * 17 * * * 18 * * * 19 * * * 20 * * * 21 * * * 22 * * * 23 * * * 24 * * * 25 * * * 26 * * * 27 * * * 28 * * * 29 * * * 30 * * *

</cli>

the pings are ignored by the router therefore it doesnt reach the other network.

A new sub-network engineering-net (192.168.10.0/24) is to be added to the ICCT network. Host engineering (192.168.10.1/32) is a cluster server for this new network. Give the settings needed to set up this host as a router to icct-net, jupiter-net, and saturn-net and a gateway for engineering-net.

The primary network interface auto eth0 iface eth0 inet static

address 192.168.1.3
network 192.168.1.0
netmask 255.255.255.0
gateway 192.168.1.1
# route to saturn-net
up    route add -net 192.168.3.0 netmask 255.255.255.0 gw 192.168.1.4
down  route del -net 192.168.3.0 netmask 255.255.255.0 gw 192.168.1.4

auto eth1 iface eth1 inet static

address 192.168.2.1

Which other files would you need to modify to correctly set up this new router?

/etc/networks/interfaces

/etc/hostname

/etc/hosts

Summarize the changes that you would you need to make to your host's network configuration to have the new engineering sub-network recognized?

Answer

Which other files would you need to modify to fully configure your host to recognizes the new engineering sub-network?

/etc/network/options

/etc/network/interfaces

I hereby submit this work for marking.

Your signature here:

Marwa Al Moosawi

575509