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====== Network Configuration: Results ======

^EG-253^Practical Internet Technology II ^
|**Name** |Abbas Ibrahim |
|**Student Number** |572278 |
|**Date of Submission** |th November 2011 |   

===== Instructions =====

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 [[#signature|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. 

===== Host Configuration =====


==== Question 1 ====
 

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

**Answer** (//delete as appropriate//):

  hostname 


==== Question 2 ====

Use the command selected in [[#question_1|Question 1]] to determine your host computer's name? What is the name?

**Answer**: 

   mimas


==== Question 3 ====

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

Your answer (//one of//):

  /etc/hostname 
  

==== Question 4 ====

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

**Answer** //one of//:

  ifconfig 


==== Question 5 ====

Use the command selected in [[#question_4|Question 4]] to complete the following table:
^ Feature ^ Value ^
| My host's IP address | 192.168.3.3|
| My network's IP address | 192.168.3.0 |
| The address used by my host to send an IP packet to all hosts on my network | 192.168.3.255  |
| The netmask of my host | 255.255.255.0 |
| The hardware address (MAC Address) of my LAN-facing network interface connection (NIC)((If your host has two or more network cards, the LAN-facing card will be the NIC assigned to your host's static IP address.)) | 00:19:d1:91:4f:c7 | 
| The frame-level (layer 1) protocol is used to send network messages to the network from my host? | Ethernet  |  




==== Question 6 ====

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

**Answer** //one of//:

  254 
  

==== Question 7 ====

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

**Answer** //one of//:

  Class C 





===== Network Configuration =====

**Answer** the following questions about your network configuration. Please copy and paste the contents of the files identified in [[#question_8|Questions 8]] and [[#question_11|11]] to your submission.





==== Question 8 ====
 

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|Question 8]]:

  auto eth0
  iface eth0 inet static
  address 192.168.3.3
  network 192.168.3.0
  netmask 255.255.255.0
  gateway 192.168.3.1



==== Question 9 ====

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

**Answer**: 

192.168.3.1

==== Question 10 ====

What is the hostname of the gateway interface?

**Answer**:

saturn


==== Question 11 ====

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|Question 11]]:

  
  127.0.0.1	mimas	localhost.localdomain	localhost
  127.0.1.1	mimas

  # /etc/hosts -- Hosts file for ICCT Private network
  #
  # IP          FQDN                       aliases
  #
  127.0.0.1     localhost.localdomain      localhost mimas
  #
  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-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-if1
  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 hosts/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 ip6-localhost ip6-loopback
  fe00::0 ip6-localnet
  ff00::0 ip6-mcastprefix
  ff02::1 ip6-allnodes
  ff02::2 ip6-allrouters
  ff02::3 ip6-allhosts
  
 
  # 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
   
==== Question 12 ====

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

**Answer**: 

saturn.icct.com            saturn saturn-if2

==== Question 13 ====

What is the purpose of the Gateway interface?

**Answer**:


The purpose of the Gateway interface is to provide a communication bridge between the internet and the networks. Moreover, its used to route messages between them. 


==== Question 14 ====

Which linux command shows the routing table for your host?

**Answer**: 
route

Run the command identified in [[#question_14|Question 14]] and reproduce its output here.

**Answer**

<cli prompt="$" comment="#">
user@host:~$ route # Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
saturn-net      *               255.255.255.0   U     0      0        0 eth0
169.254.0.0     *               255.255.0.0     U     1000   0        0 eth0
default         saturn.icct.com 0.0.0.0         UG    100    0        0 eth0

</cli>

==== Question 15 ====

How many interfaces (NICs) must a router have?

**Answer** //one of//:

  2 
  
==== Question 16 ====

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

**Answer**: 
  Enable forwarding
==== Question 17 ====

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

**Answer**: 
echo 1 > /proc/sys/net/ipv4/ip_forward
==== Question 18 ====

In which file is the setting defined in [[#question17|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|Question 17]] to make a Ubuntu host into a router?

**Answer**

ip_forward=yes


  

==== Question 19 ====

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

**Answer**: 

  up route add -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.1.3
  down route del -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.1.3



===== Checking Your Network =====

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.

==== Question 20 ====

Give and explain the output of the command ''netstat -r''. 

**Answer**
<cli prompt="$" comment="#">
user@host:~$ netstat -r
# Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
saturn-net      *               255.255.255.0   U         0 0          0 eth0
169.254.0.0     *               255.255.0.0     U         0 0          0 eth0
default         saturn.icct.com 0.0.0.0         UG        0 0          0 eth0

</cli>

Explanation: netstat -r displays the kernel routing tables.


==== Question 21 ====

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


**Answer**
<cli prompt="$" comment="#">
user@host:~$ 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      7275      0      0 0          5798      0      0      0 B
MRU
lo        16436 0        24      0      0 0            24      0      0      0 L
RU

</cli>

Explanation: netstat -i displays the interface table.


==== Question 22 ====

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

**Answer**
<cli prompt="$" comment="#">
user@host:~$ netstat -ta
# Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address           Foreign Address         State      
tcp        0      0 mimas:mysql             *:*                     LISTEN     
tcp        0      0 *:www                   *:*                     LISTEN     
tcp        0      0 *:ssh                   *:*                     LISTEN     
tcp        0      0 mimas:ipp               *:*                     LISTEN     
tcp        1      0 mimas.saturn.icct:40471 174.36.133.240-stat:www CLOSE_WAIT 
tcp        1      0 mimas.saturn.icct:40469 174.36.133.240-stat:www CLOSE_WAIT 
tcp        0      0 mimas.saturn.icct:40455 174.36.133.240-stat:www TIME_WAIT  
tcp        1      0 mimas.saturn.icct:40470 174.36.133.240-stat:www CLOSE_WAIT 
tcp        0      0 mimas.saturn.icct:40464 174.36.133.240-stat:www TIME_WAIT  
tcp        0      0 mimas.saturn.icct:40460 174.36.133.240-stat:www TIME_WAIT  
tcp        0      0 mimas.saturn.icct:40467 174.36.133.240-stat:www TIME_WAIT  
tcp6       0      0 [::]:ssh                [::]:*                  LISTEN     
tcp6       0      0 ip6-localhost:ipp       [::]:*                  LISTEN     

</cli>

Explanation: Displays all the active TCP connections and the TCP & UDP ports on the computer.

===== Testing the Connectivity of your network =====

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

==== Question 23 ====

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

**Answer**
<cli prompt="$" comment="#">
abbas@mimas:~$ traceroute dione
 traceroute to dione (192.168.3.4), 30 hops max, 60 byte packets
 1  dione.saturn.icct.com (192.168.3.4)  1.184 ms  1.187 ms  1.180 ms

</cli>  




==== Question 24 ====

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

**Answer**
<cli prompt="$" comment="#">
abbas@mimas:~$ traceroute www.swan.ac.uk
traceroute to www.swan.ac.uk (137.44.1.7), 30 hops max, 60 byte packets
 1  saturn.icct.com (192.168.3.1)  0.263 ms  0.249 ms  0.487 ms
 2  * * *
 3  * * *
 4  * * *
 5  * * *
 6  * * *
 7  * * *
 8  * * *
 9  * * *
10  * * *
11  * * *
12  * * *
13  * * *
14  * * *
15  * * *
16  * * *
17  * * *


</cli>  
The router does not forward the pings.

===== Extension Questions =====

==== Question 25 ====

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**
  iface eth0 inet static
  address 192.168.10.1
  network 192.168.10.0
  netmask 255.255.255.0
  gateway 192.168.10.1
  # route to jupiter-net
  up route add -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.1.3
  down route del -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.1.3

  # route to engineering
  up route add -net 192.168.10.0 netmask 255.255.255.0 gw 192.168.10.3
  down route del -net 192.168.10.0 netmask 255.255.255.0 gw 192.168.10.3
==== Question 26 ====

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

**Answer** 

/etc/hostname 

/etc/hosts 

/etc/networks/interfaces

/etc/resolv.conf
==== Question 27 ====

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** 

iface eth0 inet static
  address 192.168.1.4
  network 192.168.1.0
  netmask 255.255.255.0
  gateway 192.168.1.1
  # route to jupiter-net
  up route add -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.1.3
  down ro/etc/network/interfacesute del -net 192.168.2.0 netmask 255.255.255.0 gw 192.168.1.3




==== Question 27 ====

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

**Answer**

/etc/resolve.conf

/etc/hosts

/etc/nsswitch.conf

/etc/network/interfaces



I hereby submit this work for marking.

Your signature here:  --- //[[572278@swansea.ac.uk|Abbas]] 2011/12/09 16:13//