CompTIA Network+ Certification Study Guide part 77 docx

By adding an entry into the LMHOSTS file for the OFFICE1 machine, the new workstation will be able to resolve the name, get an IP address, and then use the IP address to make a successfu

Over the weekend you have installed a new NIC in a server and

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have configured the NIC to have the same static IP address that was set on the old NIC First thing Monday morning you receive a network alert that there is large number of broadcasts taking place

on the network segment where this server resides What is the probable cause for the increase in broadcasts?

A ARP resolutions

B RARP resolutions

C DNS resolutions

D Dig attempts

Correct answers and explanations: A Answer A is correct because by

replacing the NIC in the server, the IP address to MAC address information that was cached on other machines for that server is now out of date In order to communicate with the server successfully the other machines will perform an ARP broadcast requesting the MAC address that corresponds to the server’s IP address Since the replacement took place over the weekend when it was likely that many machines were off or not in use, the spike in broadcasts was not seen until Monday morning when the machines were powered on and attempting connection to the server The ARP broadcasting will subside once resolution has occurred and the machines are able to store the new MAC and IP address values in their ARP cache

Incorrect answers and explanations: B, C, and D Answer B is incorrect because

RARP is reverse ARP and in this case it is unlikely that it is being required to connect The name and the IP address of the server did not change, so DNS and other name resolution systems would have the correct information So once the name resolution has taken place to provide an IP address, the final compo-nent to retrieve is the MAC address that corresponds to the IP address ARP is responsible for mapping IP addresses to MAC addresses, not RARP RARP maps

MAC addresses to IP addresses Answer C is incorrect because DNS resolution

does not occur over a broadcast DNS resolution is directed traffic sent to the

DNS server Answer D is incorrect because Dig attempts do not occur over a

broadcast Dig is traffic that is sent directly to the DNS server

ChApTEr 12: NETworK TrouBlEShooTING METhodoloGy

You are a network consultant specializing in supporting Small

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Office Home Office (SOHO) networks One of your clients maintains an office consisting of three workstations configured

in a peer-to-peer workgroup This office does not have a server

computer at this time One of the workstations, \\OFFICE1, has

an IP address of 192.168.1.100 and has a file share that the other

three workstations are able to access using the following syntax:

\\OFFICE1\share Your client has called you in to troubleshoot a

new workstation that they have recently installed that is unable

to access this share When you arrive on site, you find that the

workstation is able to ping OFFICE1 by its IP address, but not by

its NetBIOS name What is the best way for you to allow the new

workstation to access the file share located on OFFICE1?

A Upgrade OFFICE1 to Windows 2003 server and configure the

WINS Server service

B Add an entry to the lmhosts file on the new workstation

C Add an entry to the findhosts file on the new workstation

D Upgrade OFFICE1 to Windows 2003 server and configure the

DNS service

Correct answers and explanations: B Answer B is correct, because a

Universal Naming Convention (UNC) path is being used to attempt to

connect to the OFFICE1 machine UNC paths utilize NetBIOS names for

connectivity, so the NetBIOS name of OFFICE1 must be resolved to an IP

address before a connection can be successful The LMHOSTS files is a local

text-based file which is used to resolve NetBIOS names By adding an entry

into the LMHOSTS file for the OFFICE1 machine, the new workstation will

be able to resolve the name, get an IP address, and then use the IP address to

make a successful connection to the share

Incorrect answers and explanations: A, C, and D Answer A is incorrect,

because upgrading a workstation operating system to a server operating

sys-tem is not a viable upgrade path for Windows-based syssys-tems If a fresh install

of Windows 2003 was to be performed, and WINS were to be installed, then

all of the machines in the office would need to be configured to utilize WINS

In a small office setting with so few machines, installing a server-based

sys-tem and a name resolution service like WINS is possible, but it is much

more than such a small setting requires Answer C is incorrect, because the

findhosts file doesn’t exist It is a fictional file name Answer D is incorrect,

because DNS is a service that is used for host names, and not for NetBIOS

name resolution Also, upgrading a workstation operating system to a server

operating system is not a viable upgrade path for Windows-based systems If

a fresh install of Windows 2003 was to be performed, and DNS were to be

installed, then all of the machines in the office would need to be configured

to utilize DNS In a small office setting with so few machines, installing a server-based system and a name resolution service like DNS is possible, but

it is much more than such a small setting requires

You are troubleshooting network connectivity issues on a network

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that is running Windows servers and clients Users are reporting that they are unable to send e-mail, though they have been receiv-ing messages from external users without a problem Durreceiv-ing your troubleshooting, you see the configuration item on the Windows server that is shown in Figure 12.8 Based on this information, how can you correct the issue that this office is reporting?

A Install and configure the POP3 service

B Change the startup type of the SNMP Trap Service to Automatic

C Start the Simple Mail Transport Protocol (SMTP) service

D Start the Routing and Remote Access Service

Correct answers and explanations: C Answer C is correct, because the

Simple Mail Transport Protocol (SMTP) service is utilized to send e-mail

On this server the service is in a stopped state, even though it is configured

to start automatically While the service is stopped e-mail cannot flow out-bound from the system and users will not be able to send mail until the service is restored to a Started state

FIGurE 12.8

Incorrect answers and explanations: A, B, and D Answer A is incorrect,

because POP3 is a protocol used to receive mail This question states that

users are receiving mail without an issue, and it is the sending of e-mail that

is not functioning Answer B is incorrect, because SNMP is an acronym for

Simple Network Management Protocol It is a protocol used to manage and

collect information about a network infrastructure and it is not used for

e-mail sending purposes Answer D is incorrect, because the Routing and

Remote Access Service (RRAS) is utilized to validate remote access sessions

It is not used in to send e-mail messages and therefore is not the appropriate

solution to the issue presented

You are a network consultant and have been called in to

trouble-3

shoot a connectivity issue on a UNIX network From the client’s

UNIX workstations, which of the following utilities can you use to

perform network troubleshooting? (Select all that apply.)

A Ping

B Tracert

C Pathping

D Traceroute

E Nslookup

F Dig

Correct answers and explanations: A, D, E and F Answer A is correct,

because ping is a command that can be utilized on a UNIX-based

worksta-tion in order to troubleshoot TCP/IP connectivity problems Answer D is

correct, because traceroute is a command that can be utilized on a

UNIX-based workstation in order to troubleshoot routing-related issues that may

exist Answer F is correct, because dig is a command that can be utilized

on a UNIX-based workstation in order to troubleshoot DNS-related issues

Answer E is correct, because nslookup is a command that can be utilized to

troubleshoot DNS from a Windows or a UNIX-based system

Incorrect answers and explanations: B and C Answer B is incorrect, because

tracert is a command that is used to troubleshoot routing-based issues from a

Windows-based system Answer C is incorrect, because pathping is a command

also used to troubleshoot routing-based issues from a Windows-based system

You are the network administrator for a network that employs a

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Windows 2003 server and 30 Windows XP Professional

worksta-tions The Windows 2003 server runs the DHCP service to provide

TCP/IP configuration information to the Windows XP clients You

receive a call from one of your users stating that he is unable to

browse any internal network resources or Internet websites Other users on the same subnet are able to browse without difficulty You

run the ipconfig command on the problem workstation and see the

following output:

Windows IP Configuration Host Name: IBM-A38375FF22E Primary Dns Suffix:

Node Type: Hybrid

IP Routing Enabled: No WINS Proxy Enabled: No Ethernet adapter Wireless Network Connection:

Connection-specific DNS Suffix:

Description: Intel(R) PRO/Wireless 2200BG Network Connection Physical Address: 00-1E-25-1A-D3-5A

Dhcp Enabled: Yes Autoconfiguration Enabled: Yes

IP Address: 169.254.1.96 Subnet Mask: 255.255.0.0 Default Gateway:

DHCP Server:

DNS Servers:

Lease Obtained: Tuesday, March 29, 2005 1:00:10 PM Lease Expires: Wednesday, March 30, 2005 1:00:10 PM Based on this output, why is this workstation unable to browse any network resources?

A The default gateway is unavailable

B The workstation could not contact a DHCP server

C The workstation is configured with the incorrect default gateway

D The workstation’s DHCP lease has expired

Correct answers and explanations: B Answer B is correct, because the

workstation is displaying a 169.254.1.96 IP address, which is an APIPA address APIPA is short for Automatic Private IP Address and covers a range

of 169.254.0.0 through 169.254.255.254 An address from this range is automatically assigned to a machine when it is configured to utilize DHCP, but it is not able to contact a DHCP server Typically when a machine is assigned an APIPA address it is not able to connect to with the rest of the network, since the rest of the network will most likely be utilizing a differ-ent addressing scheme In very small business networks and home network environment is it possible to rely on APIPA for addressing APIPA does not

configure variables such as a gateway, so in most corporate environments

where routers exist, APIPA isn’t appropriate for network configurations

Incorrect answers and explanations: A, C, and D Answer A is incorrect,

because a default gateway is never configured when an APIPA address has

been assigned Answer C is incorrect, because the workstation does not have

a gateway value configured; it has an APIPA address configured, which never

has an accompanying gateway value Answer D is incorrect, because when

a workstation’s DHCP lease has expired it will attempt to renew its existing

IP address It is only is if is unsuccessful in renewal that it will be forced to

abandon the currently issued IP address It will then issue an APIPA address

instead

You are the network administrator for a sales office Until now, this

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has been a small peer-to-peer network consisting of five Windows

XP workstations using lmhosts files on each workstation to

per-form name resolution The sales force has recently expanded

sig-nificantly, requiring you to purchase a Windows Server 2003 server

and 15 additional workstations You have encountered numerous

troubleshooting situations where a workstation’s lmhosts file was

missing or out of date, preventing name resolution from taking

place How can you improve the name resolution process for your

network?

A Install the DNS service on the Windows 2003 server

B Install the WINS service on the Windows 2003 server

C Install the DHCP service on the Windows 2003 server

D Install the DNS service on each Windows XP workstation

Correct answers and explanations: B Answer B is correct, because by

centralizing the name resolution service by deploying WINS, much of the

maintenance and overhead that comes with managing a distributed name

solution is removed Since once a workstation is configured to use WINS

they will automatically update and register their name and IP

informa-tion, the burden is taken off the administrator to keep the local text-based

LMHOSTS file up to date

Incorrect answers and explanations: A, C, and D Answer A is incorrect,

because DNS services are utilized for hostname resolution, and this scenario is

utilizing lmhosts files, which are used for NetBIOS name resolution Answer C

is incorrect, because DHCP is a service utilized to configure IP addresses, and

not a service used to aid in name resolution Answer D is incorrect, because

DNS is a service that is installed on server-based platforms, and not on

workstation machines For local hostname resolution on a workstation, a host’s file may be used

You are the network administrator for a large pharmaceutical

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pany that has over 1,000 workstations To simplify TCP/IP configu-ration for these numerous clients, you installed a DHCP server over

a year ago to automatically configure your clients with an IP ad-dress, as well as the following common configuration information: Subnet Mask: 255.255.0.0

Default Gateway: 172.16.0.1 DNS Servers: 172.16.0.100 172.16.0.101

As part of a recent network redesign, you had to change the default gate-way used by your clients to a different IP address: 172.16.1.1 You made the necessary change on the DHCP server, and most of your clients were updated automatically After you make this change, you receive a call from one user who no longer is able to browse the Internet You examine the TCP/IP configuration of her LAN connection (see Figure 12.9) How can you configure this workstation with the correct default gate-way information? (Each choice represents a complete solution Choose two.)

A Delete the manually configured information and select Obtain

an IP address automatically

B Run ipconfig /renew from the command prompt

C Manually update the IP address of the default gateway

D Run ipconfig /release from the command prompt

Correct answers and explanations: A and C Answer A is correct, because

by changing the configuration to Obtain an IP address automatically the machine will connect to the DHCP server to receive an IP address and also receive the configured options which include the new default gateway value

Answer C is correct, because by manually updating the IP address of the

default gateway on the client machine it will be able to connect to the correct default gateway

Incorrect answers and explanations: B and D Answer B is incorrect, because an ipconfig/renew command will force a client to attempt renewal

of its DHCP address Since this client machine is configured with a static

IP address, issuing this command will not have an effect, and will not cause the client machine to receive the correct default gateway from the DHCP

server Answer D is incorrect, because ipconfig/release command will force

a client to release its current DHCP address Since this client machine is

configured with a static IP address, issuing this command will not have an

effect, and will not cause the client machine release a DHCP address since

it doesn’t have one Also, since it is configured with a static IP address this

command will not cause the client to receive the correct default gateway

from the DHCP server

You are the administrator for the network shown in the Figure

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12.10 Based on the information in this figure, which computer is

configured incorrectly?

A Computer1

B Computer2

C Computer3

D Computer4

E Computer5

FIGurE 12.9

G Computer7

H Computer8

Correct answers and explanations: D Answer D is correct, because

Computer4 has an incorrectly configured IP address The machine is connected to a segment with the network address of 192.168.4.0/24, yet Computer4 has an IP address of 192.168.5.101/24 This will prevent the machine from properly connecting to its default gateway and any other nodes on the same segment

Incorrect answers and explanations: A, B, C, E, F, G, and H Answer A

is incorrect, because Computer1 has a correctly configured IP address The machine is connected to a segment with the network address of 192.168.3.0/24, and Computer1 has an IP address of 192.168.3.101/24

Answer B is incorrect, because Computer2 has a correctly configured IP

address The machine is connected to a segment with the network address

of 192.168.3.0/24, and Computer2 has an IP address of 192.168.3.102/24

Answer C is incorrect, because Computer3 has a correctly configured IP

address The machine is connected to a segment with the network address

of 192.168.4.0/24, and Computer3 has an IP address of 192.168.4.100/24

Answer E is incorrect, because Computer5 has a correctly configured IP FIGurE 12.10

address The machine is connected to a segment with the network address

of 192.168.1.0/24, and Computer5 has an IP address of 192.168.1.101/24

Answer F is incorrect, because Computer6 has a correctly configured IP

address The machine is connected to a segment with the network address

of 192.168.1.0/24, and Computer4 has an IP address of 192.168.1.102/24

Answer G is incorrect, because Computer7 has a correctly configured IP

address The machine is connected to a segment with the network address

of 192.168.2.0/24, and Computer7 has an IP address of 192.168.2.100/24

Answer H is incorrect, because Computer8 has a correctly configured IP

address The machine is connected to a segment with the network address of

192.168.2.0/24, and Computer8 has an IP address of 192.168.2.101/24

You are the network administrator for the network shown in Figure

8

12.11 You have recently purchased a new Windows XP

worksta-tion called Computer9 that you now need to add to Subnet C

Which of the following would be a valid IP address that would

allow Computer9 to access resources on all four subnets?

A 192.168.3.155

B 192.168.3.1

C 192.168.3.0

D 192.168.3.255

FIGurE 12.11