QA


Q&A

The questions and scenarios in this book are more difficult than what you should experience on the actual exam. The questions do not attempt to cover more breadth or depth than the exam; however, they are designed to make sure that you know the answers. Rather than allowing you to derive the answers from clues hidden inside the questions themselves, the questions challenge your understanding and recall of the subject. Hopefully, these questions will help limit the number of exam questions on which you narrow your choices to two options and then guess.

You can find the answers to these questions in Appendix A.

1.

What commands can configure a Catalyst 4500 switch as the Root Bridge on VLAN 10, assuming that the other switches are using the default STP values?

2.

Using your Root Bridge answer from question 1, what commands can configure a Catalyst 3550 switch as a secondary or backup Root Bridge on VLAN 10?

3.

Which of the following switches will become the Root Bridge, given the information in the following table? Which switch will become the secondary Root Bridge if the Root Bridge fails?

Switch Name

Bridge Priority

MAC Address

Port Costs

Catalyst A

32,768

00-d0-10-34-26-a0

All are 19.

Catalyst B

32,768

00-d0-10-34-24-a0

All are 4.

Catalyst C

32,767

00-d0-10-34-27-a0

All are 19.

Catalyst D

32,769

00-d0-10-34-24-a1

All are 19.


Questions 4 through 7 are based on a network that contains two switches, Catalyst A and B. Their bridge priorities and MAC addresses are 32,768:0000.aaaa.aaaa and 32,768:0000.bbbb.bbbb, respectively.

4.

Which switch will become the Root Bridge?

5.

If switch B's bridge priority is changed to 10,000, which one will be root?

6.

If switch B's bridge priority is changed to 32,769, which one will be root?

7.

If switch C is introduced with 40000:0000.0000.cccc, which will be the secondary root?

8.

Suppose that a switch is configured with the spanning-tree vlan 10 root primary command. Then, another switch is connected to the network. The new switch has a bridge priority of 8192. Which one of the following happens?

  1. When the new switch advertises itself, the original Root Bridge detects it and lower its bridge priority to 4096 less than the new switch.

  2. The new switch becomes and stays the Root Bridge (bridge priority 8192).

  3. No change; both switches keep their current bridge priorities.

  4. The new switch detects that a Root Bridge already exists and raises its own bridge priority to 32,768.

9.

Three switches in a network have the following bridge priorities: 32,768, 16,384, and 8192. If a fourth switch is configured with spanning-tree vlan 1 root secondary, what is the bridge priority of the switches that become the primary and secondary Root Bridges?

10.

What STP timer values automatically can be modified by setting the network diameter?

11.

Which STP timer determines how long a port stays in the Listening state? What is its default value?

12.

What is the purpose of the Max Age timer?

13.

Three switches are connected to each other, forming a triangle shape. STP prevents a loop from forming. What is the most accurate value that could be used for the network diameter?

14.

Which of the following will not benefit from STP UplinkFast?

  1. An access-layer switch with one uplink port

  2. An access-layer switch with two uplink ports

  3. An access-layer switch with three uplink ports

  4. An access-layer switch with four uplink ports

15.

What command can enable the STP PortFast feature on a switch? What configuration mode must you enter first?

16.

What happens if the STP Hello Time is decreased to 1 second in an effort to speed up STP convergence? What happens if the Hello Time is increased to 10 seconds?

17.

What switch command safely can adjust the STP timers on the Root Bridge in VLAN 7? Assume that the network consists of Catalysts A, B, and C, all connected to each other in a triangle fashion.

For questions 18 and 19, refer to the following output:

 Switch# show spanning-tree vlan 50 VLAN50   Spanning tree enabled protocol ieee   Root ID    Priority    8000              Address     00d0.0457.3831              Cost        12              Port        49 (GigabitEthernet0/1)              Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec Bridge ID    Priority    32818 (priority 32768 sys-id-ext 50)              Address     0009.b7ee.9800              Hello Time   2 sec Max Age 20 sec Forward Delay 15 sec              Aging Time 300 Interface                                    Designated Name                Port ID Prio  Cost Sts   Cost Bridge ID            Port ID -----------------   ------- --- ------ ---   ---- -------------------- ------- FastEthernet0/1     128.1   128     19 FWD     12 32818 0009.b7ee.9800 128.1 FastEthernet0/2     128.2   128     19 FWD     12 32818 0009.b7ee.9800 128.2 FastEthernet0/4     128.4   128    100 FWD     12 32818 0009.b7ee.9800 128.4 FastEthernet0/7     128.7   128     19 FWD     12 32818 0009.b7ee.9800 128.7 FastEthernet0/8     128.8   128     19 FWD     12 32818 0009.b7ee.9800 128.8 FastEthernet0/9     128.9   128     19 FWD     12 32818 0009.b7ee.9800 128.9 FastEthernet0/10    128.10  128     19 FWD     12 32818 0009.b7ee.9800 128.10 FastEthernet0/11    128.11  128     19 FWD     12 32818 0009.b7ee.9800 128.11 FastEthernet0/12    128.12  128     19 FWD     12 32818 0009.b7ee.9800 128.12 FastEthernet0/17    128.13  128     19 FWD     12 32818 0009.b7ee.9800 128.13 FastEthernet0/20    128.16  128     19 FWD     12 32818 0009.b7ee.9800 128.16 FastEthernet0/21    128.17  128     19 FWD     12 32818 0009.b7ee.9800 128.17 FastEthernet0/23    128.19  128     19 FWD     12 32818 0009.b7ee.9800 128.19 FastEthernet0/24    128.20  128     19 FWD     12 32818 0009.b7ee.9800 128.20 

18.

What is the Bridge ID for the current Root Bridge? Is the switch that produced this output the actual Root Bridge?

19.

What is the path cost of interface FastEthernet 0/4, and why is it different from the others?

20.

Why does the column marked "Designated Bridge ID" have the same value for every switch port?

21.

Suppose that you need to troubleshoot your spanning-tree topology and operation. What commands and information can you use on a switch to find information about the current STP topology in VLAN 39?



CCNP Self-Study(c) CCNP BCMSN Exam Certification Guide
Red Hat Fedora 5 Unleashed
ISBN: N/A
EAN: 2147483647
Year: 2003
Pages: 177

flylib.com © 2008-2017.
If you may any questions please contact us: flylib@qtcs.net