Basic knowledge and theory Router
3. Configure the GNS3 package itself Choose Edit → Preferences, then Dynamips (Fig 9.7) Check the tick Enable ghost IOS sup-
port, that will allow to use the same IOS image in different rout-
ers and that will reduce RAM consumption. Check the state of virtualization component Dynamips by pressing the Test button, the response indicating success should be indicated.
Fig. 9.6. IOS image and hypervisors configuration window
Capture tab allows setting the capture directory to which all the intercepted network packets go. Qemu tab can be used to configure network devices other than routers. Set the path to quemu image in Quemu Host tab (C:\Documents and Settings\...\linux-microcore-
3.8.2.img), choose name PC and save the configuration. Test Qemu
preparedness by pressing Test in General Settings. Close the win- dow by pressing OK.
4. Add the router to the network by dragging the correspond- ing icon. Power it on by pressing the green triangle. Check the amount of used CPU and RAM on the Laboratory PC (Windows Task Manager → Performance), what process re- lated to GNS3 is using it. Press left mouse button on the router object and select Idle PC. GNS3 will count most probable Idle- PC value and mark it with a star, select it. Idle-PC value de- pends on router IOS and configuration used. It identifies router process on the physical computer. Check the CPU load again; the load should be reduced drastically.
5. Change the name of the router: stop it at first by pressing red rectangle icon in the toolbar and then click the left mouse but- ton on router object and choose Change the hostname, name the router with your variant number word.
6. Add Ethernet switch a component. Connect routers FastEthernet 0/0 interface to switch port by pressing Add Link button on the toolbar. Check the configuration of the switch, what port types are available.
7. Start the router by pressing the green triangle and connect to the router console by pressing the black button on the toolbar. New putty window will open, click with the mouse in it. If the configuration wizard will be suggested, refuse it by entering No and pressing Enter.
8. Enable privileged mode with the command enable and the con- figuration mode with: configure terminal.
(variant name)#configure terminal
Enter configuration commands, one per line. End with CNTL/Z. (variant name) (config)#
8.1. If the hostname of the router is not set by configuring set host- name in the Task 6, change the hostname using command:
hostname (variant name) from the configuration mode.
9. Configure network interface by choosing it, configuring IP ad- dress and activating the interface (variant number X is used in your IP address):
(variant name) (config)#interface FastEthernet 0/0
(variant name) (config-if)#ip address 192.168.X.1 255.255.255.0 (variant name) (config-if)#no shutdown
10. Leave the interface configuration mode and return to configura- tion mode with: exit. Router can show some informational an- nouncement and not return a carriage, in that case press Enter.
(variant name) (config-if)#exit (variant name) (config)#exit (variant name)#
11. Check the router configuration.
11.1. Check how network interface is configured: show ip in- terface brief. Analyze the presented information. Check the more detail interface information: show interfaces.
11.2. Check the running configuration: show running-config. To scroll one line down press Enter, to scroll down a whole page – Space.
12. Secure the device by configuring the passwords.
12.1. Configure activation password – cisco, console (line con-
sole 0) – (variant name) as a password and telnet (line vty 0-4) password – lab. Configuration must be performed
from the configuration mode. Activation password can be saved in open or ciphered form. All other passwords are in
open form, addition services must be turned on in order to cipher them. Passwords can be enabled with this sequence of the commands:
(variant name) >enable
(variant name) #configure terminal
(variant name) (config)#enable secret cisco (variant name) (config)#line console 0 (variant name) (config-line)#login
(variant name) (config-line)#password (variant name) (variant name) (config-line)#line vty 0 4
(variant name) (config-line)#login
(variant name) (config-line)#password lab (variant name) (config-line)#exit
2.2. Disconnect from privileged mode and connect with enter- ing the passwords.
3. Check the running configuration, then starting configuration. Save the running configuration to the starting configuration. Analyse the running configuration.
(variant name) # show running-config (variant name) # show startup-config
(variant name) # copy running-config startup-config (variant name) # show startup-config
14. Add and configure the Quemu host.
4.. Add the Quemu host and connect it to the switch port 2 using FastEthernet link. Use e0 network interface on the
Quemu host. Power on the Quemu host and wait till it loads.
Progress will be seen in newly opened window. Loading can take some time.
4.2. Clicking on the Quemu host window allow you to config- ure the host. To regain the control of your mouse press Ctrl
and Alt on the right at one time. For numeric values use the number row on the top of the keyboard.
14.3. Configure network interface eth0, it corresponds to e0 used to connect to the router:
sudo ifconfig eth0 192.168.X.5 netmask 255.255.255.0.
14.4. Check the configuration: ifconfig eth0.
4.5. Send ICMP packets using ping command: ping
192.168.(variant name).1, to stop the pinging press: Ctrl+C.
4.6. Connect to the router using telnet command: telnet
192.168.(variant name).1 input the configured password.
5. If the pinging and telneting succeeded exit the GNS3 saving the topology and configuration. Check if the laboratory work was saved by loading it and checking the configuration on the router. To save the router configuration use the command write, saving of the Qemu settings is complicated, so we will not save them.
Content of report
. Objectives of the work.
2. Review the abilities of the GNS3 package.
3. Describe the process of computer resource optimization (Task 4).
4. Describe GNS3 switch configuration options (Task 6).
5. What is the sequence of commands used to configure network interface (Tasks 8, 9 and 0)?
6. How the status of the network interfaces can be checked (Task )?
7. What types of router access passwords can be configured (Task 2)?
8. What files contain router configuration, how they differ, how to save a configuration (Task 13)?
9. How the network configuration of the Qemu host is performed (Task 4)?
0. General conclusions of the work.
Review questions and problems
. What applications are incorporated in to GNS3 package, what is their purpose?
2. What are the shortcomings of GNS3 package?
3. What are router configuration modes, what are they used for? 4. How the router can be accessed for configuration?
Literature
Cisco 3640 router data sheet. http://www.cisco.com/en/US/products/hw/ routers/ps274/products_data_sheet0986a008009f6f.html.
GNS3 Tutorial. http://downloads.sourceforge.net/gns-3/GNS3-0.5-tutorial. pdf?download.
Olifer, N., Olifer, V. 2006. Computer Networks: Principles, Technologies and Protocols for Network Design. Wiley. 000 p. ISBN-3: 978- 0470869826.
Singh, A. K. 2005. Computer Network. Laxmi Publications. 8 p. ISBN- 3: 978-87008702.