Review Questions The following questions are designed to test your understanding of this chapter s material. For more information on how to get additional questions, please see www.lammle.com/ccn a. You can find the answers to these questions in Appendix B, Answers to Review Questions. 1. You receive the following output from a switch: S2#sh spanning-tree VLAN0001 Spanning tree enabled protocol rstp Root ID Priority 32769 Address 0001.42A7.A603 Cost 4 Port 26(GigabitEthernet1/2) Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec [output cut] Which are true regarding this switch? (Choose two.) A. The switch is a root bridge. B. The switch is a non-root bridge. C. The root bridge is four switches away. D. The switch is running 802.1w. E. The switch is running STP PVST+. 2. You have configured your switches with the spanning-tree vlan x root primary and spanning-tree vlan x root secondarycommands. Which of the following tertiary switch will take over if both switches fail? A. A switch with priority 4096 B. A switch with priority 8192 C. A switch with priority 12288 D. A switch with priority 20480 3. Which of the following would you use to find the VLANs for which your switch is the root bridge? (Choose two.) A. show spanning-tree B. show root all C. show spanning-tree port root VLAN D. show spanning-tree summary
4. You want to run the new 802.1w on your switches. Which of the following would enable this protocol? A. Switch(config)#spanning-tree mode rapid-pvst B. Switch#spanning-tree mode rapid-pvst C. Switch(config)#spanning-tree mode 802.1w D. Switch#spanning-tree mode 802.1w 5. Which of the following is a layer 2 protocol used to maintain a loop-free network? A. VTP B. STP C. RIP D. CDP 6. Which statement describes a spanning-tree network that has converged? A. All switch and bridge ports are in the forwarding state. B. All switch and bridge ports are assigned as either root or designated ports. C. All switch and bridge ports are in either the forwarding or blocking state. D. All switch and bridge ports are either blocking or looping. 7. Which of the following modes enable LACP EtherChannel? (Choose two.) A. On B. Prevent C. Passive D. Auto E. Active F. Desirable 8. Which of the following are true regarding RSTP? (Choose three.) A. RSTP speeds the recalculation of the spanning tree when the layer 2 network topology changes. B. RSTP is an IEEE standard that redefines STP port roles, states, and BPDUs. C. RSTP is extremely proactive and very quick, and therefore it absolutely needs the 802.1 delay timers. D. RSTP (802.1w) supersedes 802.1d while remaining proprietary. E. All of the 802.1d terminology and most parameters have been changed. F. 802.1w is capable of reverting to 802.1d to interoperate with traditional switches on a perport basis. 9. What does BPDU Guard perform? A. Makes sure the port is receiving BPDUs from the correct upstream switch. B. Makes sure the port is not receiving BPDUs from the upstream switch, only the root. C. If a BPDU is received on a BPDU Guard port, PortFast is used to shut down the port. D. Shuts down a port if a BPDU is seen on that port.
10. How many bits is the sys-id-ext field in a BPDU? A. 4 B. 8 C. 12 D. 16 11. There are four connections between two switches running RSTP PVST+ and you want to figure out how to achieve higher bandwidth without sacrificing the resiliency that RSTP provides. What can you configure between these two switches to achieve higher bandwidth than the default configuration is already providing? A. Set PortFast and BPDU Guard, which provides faster convergence. B. Configure unequal cost load balancing with RSTP PVST+. C. Place all four links into the same EtherChannel bundle. D. Configure PPP and use multilink. 12. In which circumstance are multiple copies of the same unicast frame likely to be transmitted in a switched LAN? A. During high-traffic periods B. After broken links are reestablished C. When upper-layer protocols require high reliability D. In an improperly implemented redundant topology 13. You want to configure LACP. Which do you need to make sure are configured exactly the same on all switch interfaces you are using? (Choose three.) A. Virtual MAC address B. Port speeds C. Duplex D. PortFast enabled E. VLAN information 14. Which of the following modes enable PAgP EtherChannel? (Choose two.) A. On B. Prevent C. Passive D. Auto E. Active F. Desirable
15. For this question, refer to the following illustration. SB s RP to the root bridge has failed. What is the new cost for SB to make a single path to the root bridge? A. 4 B. 8 C. 23 D. 12 16. Which of the following would put switch interfaces into EtherChannel port number 1, using LACP? (Choose two.) A. Switch(config)#interface port-channel B. Switch(config)#channel-group 1 mode active C. Switch#interface port-channel 1 D. Switch(config-if)#channel-group 1 mode active 17. Which two commands would guarantee your switch to be the root bridge for VLAN 30? (Choose two.) A. spanning-tree vlan 30 priority 0 B. spanning-tree vlan 30 priority 16384 C. spanning-tree vlan 30 root guarantee D. spanning-tree vlan 30 root primary
18. Why does Cisco use its proprietary extension of PVST+ with STP and RSTP? A. Root bridge placement enables faster convergence as well as optimal path determination. B. Non-root bridge placement clearly enables faster convergence as well as optimal path determination. C. PVST+ allows for faster discarding of non-ip frames. D. PVST+ is actually an IEEE standard called 802.1w. 19. Which are states in 802.1d? (Choose all that apply.) A. Blocking B. Discarding C. Listening D. Learning E. Forwarding F. Alternate 20. Which of the following are roles in STP? (Choose all that apply.) A. Blocking B. Discarding C. Root D. Non-designated E. Forwarding F. Designated