12. Troubleshooting a Simple Network

Question 1

Which troubleshooting method works from the physical layer in the OSI model up to the application layer?

Answer 1

The bottom-up method.

Question 2

Which troubleshooting method starts with testing Layer 3?

Answer 2

The divide-and-conquer method.

Question 3

What is the Cisco IOS command to view logging settings?

Answer 3

Router# show logging

Question 4

What is the Cisco IOS command to enable the router to send logging information to a terminal session?

Answer 4

Router# terminal monitor

Question 5

Name the three parameters checked by using ping

Answer 5

1. Whether a remote host is active or inactive.
2. The round-trip time (RTT) in communicating with the host.
3. Packet Loss.

Question 6

When pinging a host from a Cisco device, what symbol indicates that a reply was received within the expected timeout?

Answer 6

An exclamation point (!)

Question 7

When pinging a host from a Cisco device, what symbol indicates that a reply was not received before the timeout expired?

Answer 7

A period (.)

Question 8

What Transport Layer protocol is used by Cisco devices when using the traceroute command?

Answer 8

UDP

Question 9

What is the Cisco IOS command to view the arp table? (two answers)

Answer 9

Router# show arp
or
Router# show ip arp

Question 10

What is the Microsoft Windows command to view the arp table?

Answer 10

> arp -a

Question 11

What is the Microsoft Windows command to view IPv4 address information?

Answer 11

> ipconfig /all

Question 12

What is the Cisco IOS command to see a brief overview of interface IPv4 addressing and status info?

Answer 12

Router# show ip interface brief

Question 13

List the three sources of Fiber media problems.

Answer 13

1. Microbend and macrobend losses
2. Splice losses.
3. Dirty connectors.

Question 14

What Cisco IOS command will let you examine duplex and speed settings on a switch port?

Answer 14

Switch# show interfaces

Question 15

In the output from a “show interfaces” command, what do Input queue drops indicate?

Answer 15

Input queue drops indicate that more traffic was delivered to the device than it could process.

Question 16

In the output from a “show interfaces” command, what do Output queue drops indicate?

Answer 16

Output queue drops indicate that packets were dropped due to congestion on the interface.

Question 17

In the output from a “show interfaces” command, what do Input errors indicate?

Answer 17

Input errors indicate errors experienced during the reception of the frame, such as CRC errors.

Question 18

What are CRC errors?

Answer 18

Cyclic Redundancy Check errors.

Question 19

In the output from a “show interfaces” command, what do Output errors indicate?

Answer 19

Output errors indicate errors during the transmission of the frame. (Collisions)

Question 20

Name two Microsoft Windows commands to determine the default gateway IP address.

Answer 20

> ipconifg

> route print