Table of Contents
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 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 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 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)1) | 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 Questions 8 and 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:
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:
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 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 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?
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: — Abbas 2011/12/09 16:13