Networking Chapter 10 Homework Disabled Network Simulator Activities Using

Chapter 10: Command-Line Tools

Core Idea

The focus of this chapter is on the name and use of command-line utilities.

Instructor Focus

This chapter should all be about hands-on practice of command line utilities wherever possible.

The students should come through the chapter with an understanding of how these commands

Network Objectives covered in this Chapter/Lesson

x 5.2 Given a scenario, use the appropriate tool.

Terminology

Make an effort to define the following terms for the designated areas. After defining these,

calling on the students for repeat definitions as you progress through the slide deck will help

them retain the terminology.

Command-Line Utilities (for Windows and/or UNIX):

x arp command

x ipconfig command

x nbtstat command

x netstat command

Focus Questions

x What are some of the more useful Microsoft Windows commands for configuring and

troubleshooting network clients and servers?

x What are some of the more useful UNIX commands for configuring and troubleshooting

network clients and servers?

Icebreaker Discussion

Choose one or both of the following:

1. What is the benefit of using command-line utilities instead of GUI utilities for network

configuration?

This should be a discussion of the benefits and drawbacks of both command-line interfaces

Icebreaker Activity

1. Use the command arp -a on your local machine; what information is given when you enter

this command?

This is a start to the practice that will be used throughout the main activities in this chapter.

The memorization of these commands and their information is necessary for the exam

Interface: 192.168.1.4 — 0xb

Internet Address Physical Address Type

192.168.1.255 ff-ff-ff-ff-ff-ff static

224.0.0.251 01-00-5e-00-00-fb static

239.255.255.250 01-00-5e-7f-ff-fa static

Main Activities

1. Command-Line Practice

For this activity, you will demonstrate the command-line utilities that are part of the Network+

exam. If at all possible, allow the students to use these on their own so that they get a feel for

(1) ipconfig: This is used to display information on the current DHCP configuration. It can also be

used to release or renew a DHCP lease. The option /all will display summary information, as

shown in the following example. Analyze the summary information with your class.

C:\Users\X>ipconfig /all

Windows IP Configuration

DHCP Enabled. . . . . . . . . . . : Yes

Autoconfiguration Enabled . . . . : Yes

Link-local IPv6 Address . . . . . : fe80::f9e7:1a38:7708:9868%11(Preferred)

IPv4 Address. . . . . . . . . . . : 192.168.1.4(Preferred)

Subnet Mask . . . . . . . . . . . : 255.255.255.0

Media State . . . . . . . . . . . : Media disconnected

Connection-specific DNS Suffix . : home

Description . . . . . . . . . . . : Microsoft ISATAP Adapter

Physical Address. . . . . . . . . : 00-00-00-00-00-00-00-E0

DHCP Enabled. . . . . . . . . . . : No

Link-local IPv6 Address . . . . . : fe80::242a:1128:3f57:fefb%12(Preferred)

Default Gateway . . . . . . . . . : ::

NetBIOS over Tcpip. . . . . . . . : Disabled

Chapter 10: Network Simulator Activities

x Using ARP to discover a MAC Address

(2) netstat: This command displays connection information for IP-based networks. Using the

argument -a will display information on active connections. An output example of this is shown

here. Note the local and foreign address connections, in addition to the protocol information

and connection state.

Active Connections

Proto Local Address Foreign Address State

TCP 0.0.0.0:135 Astrik:0 LISTENING

TCP 0.0.0.0:2869 Astrik:0 LISTENING

TCP 0.0.0.0:49152 Astrik:0 LISTENING

TCP 0.0.0.0:49154 Astrik:0 LISTENING

TCP 0.0.0.0:49157 Astrik:0 LISTENING

TCP 127.0.0.1:5354 Astrik:49155 ESTABLISHED

TCP 127.0.0.1:9422 Astrik:0 LISTENING

TCP 127.0.0.1:27015 Astrik:0 LISTENING

TCP 127.0.0.1:49155 Astrik:5354 ESTABLISHED

TCP 127.0.0.1:53584 Astrik:53585 ESTABLISHED

TCP 127.0.0.1:53586 Astrik:53587 ESTABLISHED

TCP 127.0.0.1:55568 Astrik:0 LISTENING

TCP 192.168.1.4:139 Astrik:0 LISTENING

TCP 192.168.1.4:52854 by2msg3020407:http ESTABLISHED

TCP 192.168.1.4:52919 securemail:https TIME_WAIT

TCP 192.168.1.4:52924 ec2-23-21-182-103:http TIME_WAIT

TCP 192.168.1.4:52926 securemail:https ESTABLISHED

TCP 192.168.1.4:53394 a23-66-231-48:http CLOSE_WAIT

TCP 192.168.1.4:64322 63.116.246.35:http CLOSE_WAIT

TCP 192.168.1.4:64916 lga15s28-in-f6:http CLOSE_WAIT

TCP [::]:135 Astrik:0 LISTENING

TCP [::]:445 Astrik:0 LISTENING

TCP [::]:2869 Astrik:0 LISTENING

TCP [::]:5357 Astrik:0 LISTENING

TCP [::]:49157 Astrik:0 LISTENING

TCP [::1]:55568 Astrik:0 LISTENING

TCP [::1]:55569 Astrik:0 LISTENING

UDP 0.0.0.0:3702 *:*

UDP 0.0.0.0:4500 *:*

UDP 0.0.0.0:49154 *:*

UDP 0.0.0.0:57991 *:*

UDP 127.0.0.1:1900 *:*

UDP 127.0.0.1:49153 *:*

UDP 127.0.0.1:49159 *:*

UDP 127.0.0.1:51212 *:*

UDP 127.0.0.1:56012 *:*

UDP 127.0.0.1:58927 *:*

UDP 127.0.0.1:60463 *:*

UDP 192.168.1.4:138 *:*

UDP 192.168.1.4:5353 *:*

UDP 192.168.1.4:56011 *:*

UDP [::]:500 *:*

UDP [::]:3702 *:*

Using the argument -r will show the routing table, as shown in the following example:

C:\Users\X>netstat -r

===========================================================================

Interface List

1………………………Software Loopback Interface 1

12…00 00 00 00 00 00 00 e0 Teredo Tunneling Pseudo-Interface

===========================================================================

IPv4 Route Table

===========================================================================

Active Routes:

Network Destination Netmask Gateway Interface Metric

0.0.0.0 0.0.0.0 192.168.1.1 192.168.1.4 25

127.0.0.1 255.255.255.255 On-link 127.0.0.1 306

192.168.1.0 255.255.255.0 On-link 192.168.1.4 281

192.168.1.255 255.255.255.255 On-link 192.168.1.4 281

224.0.0.0 240.0.0.0 On-link 192.168.1.4 281

255.255.255.255 255.255.255.255 On-link 192.168.1.4 281

===========================================================================

Persistent Routes:

None

IPv6 Route Table

===========================================================================

Active Routes:

If Metric Network Destination Gateway

12 58 2001::/32 On-link

12 306 2001:0:4137:9e76:242a:1128:3f57:fefb/128

11 281 fe80::f9e7:1a38:7708:9868/128

On-link

Persistent Routes:None

ping: This command tests a connection between the machine and a remote host. The target

name can be specified as an IP address or a domain name after the command line. An example

of this is shown here:

3) C:\Users\X>ping 192.168.1.1

Pinging 192.168.1.1 with 32 bytes of data:

Reply from 192.168.1.1: bytes=32 time=11ms TTL=64

Chapter 10: Network Simulator Activities

x Using netstat to troubleshoot connectivity

x Using ping to troubleshoot connectivity

x Using extended ping (command switches) to troubleshoot connectivity

x Using ipconfig, ping, arp, and tracert together to troubleshoot connectivity

(3) nslookup: This is used to resolve FDQN domains to an address. It has an interactive mode

that is enabled when you do not add an FDQN as an argument. An example of the

noninteractive output is shown here:

(4)

(5) route: This command enables you to display the current routing table of the device. The

print argument will show the complete routing table results. An example of this is shown here:

C:\Users\X>route print

===========================================================================

Interface List

1………………………Software Loopback Interface 1

12…00 00 00 00 00 00 00 e0 Teredo Tunneling Pseudo-Interface

===========================================================================

IPv4 Route Table

===========================================================================

Active Routes:

Network Destination Netmask Gateway Interface Metric

0.0.0.0 0.0.0.0 192.168.1.1 192.168.1.4 25

127.0.0.1 255.255.255.255 On-link 127.0.0.1 306

192.168.1.0 255.255.255.0 On-link 192.168.1.4 281

192.168.1.255 255.255.255.255 On-link 192.168.1.4 281

224.0.0.0 240.0.0.0 On-link 192.168.1.4 281

255.255.255.255 255.255.255.255 On-link 192.168.1.4 281

===========================================================================

Persistent Routes:

None

IPv6 Route Table

===========================================================================

Active Routes:

If Metric Network Destination Gateway

12 58 ::/0 On-link

1 306 ::1/128 On-link

Chapter 10: Network Simulator Activities

(6) tracert: This command pings every router hop from a source to a destination and reports the

[71.188.123

[130.81.

[130.8

1.17.6]

6 18 ms 19 ms 20 ms 0.so-0-0-0.XT1.NYC4.ALTER.NET [152.63.1.41]

[204.70.19

6.122]

11 104 ms 104 ms 98 ms hr1-tengig-13-0-0.waltham2bo2.savvis.net

.198.182]

12 98 ms 106 ms 95 ms das3-v3037.bo2.savvis.net [209.202.187.178]

13 98 ms 96 ms 100 ms blhosting.bridgelinesw.com [64.14.81.46]

14 98 ms 96 ms 97 ms 64.28.85.15

Trace complete.

Chapter 10: Network Simulator Activities

x Matching Command Output to Commands

Quiz Questions

You can ask the following questions either in class for a group discussion or for individual practice. If

you ask them for individual practice, review in class to make sure everyone properly understands

the content.

1. Which command-line utilities for networking are common to both Windows and UNIX machines?

2. What are the uses and potential problems of using the ping command?

The ping command is used to test connectivity between any two Layer 3 devices. This will give

3. Briefly explain the operation the tracert (or traceroute) command.

The tracert (or traceroute on UNIX) provides a step-by-step pathway between the device and

4. Consider that you have pinged your default gateway, and you get back a response. However,

you are unable to reach the Internet. How could you verify that the machine you pinged was in

fact, the default gateway, and not another machine on the network?

By using the “ARP –a” command immediately after the gateway ping, you can match the MAC