Comment – you should have filled this table in!

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?

hostname 

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

callisto

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

/etc/hostname 

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

ifconfig 

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

Comment No, Ethernet!

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?

/etc/network/interfaces 

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

auto eth0
iface eth0  inet static
address 192.168.2.2
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?

/etc/hosts 

Please include a listing of the file chosen in answer to Question 11:

# /etc/hosts - Hosts file for ICCT private network
127.0.0.1	callisto	localhost.localdomain	localhost
127.0.1.1	icct-desktop7
192.168.1.1	solaris.icct.com	solaris inet-gateway
192.168.1.2	venus.icct.com		venus www
# Jupiter Cluster
192.168.1.3	gw-jupiter.icct.com	gw-planets jupiter-if1
192.168.2.1	jupiter.icct.com	jupiter jupiter-if2
192.168.2.2	callisto.jupiter.icct.com	callisto
192.168.2.3	europa.jupiter.icct.com		europa
192.168.2.4	ganymede.jupiter.icct.com	ganymede
# Saturn Cluster
192.168.1.4	gw-saturn.icct.com	gw-saturn saturn-if1
192.168.3.1	saturn.icct.com		saturn saturn-if2
192.168.3.2	dione.saturn.icct.com	dione
192.168.3.3	tethys.saturn.icct.com	tethys
192.168.3.4	titan.saturn.icct.com	titan
# 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?

Defines a simple and universal interface between web servers and web applications or frameworks to receive data back and forth.

Comment No: that's C-GI!

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=“$” comment=“#”> icct@callisto:~$ 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 icct@callisto:~$

</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?

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 and change the line ip_forward=no to ip_forward=yes 

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

ip_forward=yes
spoofprotect=yes

Comment Only first line is needed to enable IP forwarding.

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.

Answer <cli prompt=“$” comment=“#”> icct@callisto:~$ netstat -r 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 icct@callisto:~$

</cli>

Netstat can print network connections, routing tables, interface statistics, masquerade connections, and multicast memberships. The -r part displays the kernel routing tables.

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

Answer <cli prompt=“$” comment=“#”> icct@callisto:~$ netstat -i 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 18176 0 0 0 16177 0 0 0 BMRU lo 16436 0 1260 0 0 0 1260 0 0 0 LRU icct@callisto:~$

.. </cli>

The -i part displays a table of all network interfaces, (Or if specified,the specified interface).

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

Answer <cli prompt=“$” comment=“#”> icct@callisto:~$ netstat -ta Active Internet connections (servers and established) Proto Recv-Q Send-Q Local Address Foreign Address State tcp 0 0 callisto:ipp *:* LISTEN tcp 0 0 callisto.jupiter.:34456 server77-68-39-12.l:www TIME_WAIT tcp 0 0 callisto.jupiter.:34467 server77-68-39-12.l:www TIME_WAIT tcp 0 0 callisto.jupiter.:34461 server77-68-39-12.l:www ESTABLISHED tcp 0 0 callisto.jupiter.:34462 server77-68-39-12.l:www TIME_WAIT tcp6 0 0 localhost:ipp [::]:* LISTEN icct@callisto:~$ </cli> The -ta part shows all active internet connections (if they are servers or established) and their current state.

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.

Answer <cli prompt=“$” comment=“#”> icct@callisto:~$ traceroute titan traceroute to titan (192.168.3.4), 30 hops max, 60 byte packets 1 jupiter.icct.com (192.168.2.1) 1.237 ms 1.226 ms 1.214 ms 2 jupiter.icct.com (192.168.2.1) 3010.293 ms !H 3010.290 ms !H 3010.279 ms !H

</cli>

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

Answer <cli prompt=“$” comment=“#”> icct@callisto:~$ traceroute www.swan.ac.uk traceroute to www.swan.ac.uk (137.44.1.7), 30 hops max, 60 byte packets 1 jupiter.icct.com (192.168.2.1) 0.898 ms 0.888 ms 0.876 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 router does not forward the pings.

Comment Which router?

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.

Answer

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

/etc/hosts
/etc/networks
/etc/network/interfaces
/etc/network/options

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?

All these files on the host:
/etc/hosts
/etc/networks
/etc/network/interfaces
/etc/network/options

I hereby submit this work for marking.

Your signature here:

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