CCNA 3 Scaling Networks Chapter 2 V5.01 - V5.03 Exam Answers 2015
1. Which protocol provides up to 16 instances of RSTP, combines many VLANs with the same physical and logical topology into a common RSTP instance, and provides support for PortFast, BPDU guard, BPDU filter, root guard, and loop guard?
STP
Rapid PVST+
PVST+
MST*
2. Which two types of spanning tree protocols can cause suboptimal traffic flows because they assume only one spanning-tree instance for the entire bridged network? (Choose two.)
STP*
RSTP*
MSTP
Rapid PVST+
PVST+
3.
Refer to the exhibit. Which protocol information is being displayed in the output?
HSRP
VRRP
GLBP*
FHRP
4. A network administrator is preparing the implementation of Rapid PVST+ on a production network. How are the Rapid PVST+ link types determined on the switch interfaces?
Link types can only be configured on access ports configured with a single VLAN.
Link types must be configured with specific port configuration commands.
Link types are determined automatically.*
Link types can only be determined if PortFast has been configured.
5. Which RSTP ports are connected to end devices?
root ports
designated ports
trunk ports
edge ports*
6. If no bridge priority is configured in PVST, which criteria is considered when electing the root bridge?
highest IP address
lowest MAC address*
lowest IP address
highest MAC address
7. Which port state will switch ports immediately transition to when configured for PortFast?
learning
blocking
forwarding*
listening
8. To obtain an overview of the spanning tree status of a switched network, a network engineer issues the show spanning-tree command on a switch. Which two items of information will this command display? (Choose two.)
The role of the ports in all VLANs.*
The IP address of the management VLAN interface.
The number of broadcasts received on each root port.
The status of native VLAN ports.
The root bridge BID.*
9.
Launch PT Hide and Save PT
Open the PT Activity. Perform the tasks in the activity instructions and then answer the question.
Which switch is the root bridge?
Switch_1
Switch_2
Switch_4*
Switch_3
10. Fill in the blank. Do not use abbreviations.
The spanning-tree ” mode rapid-pvst ” global configuration command is used to enable Rapid PVST+.
11. Which STP priority configuration would ensure that a switch would always be the root switch?
spanning-tree vlan 10 root primary
spanning-tree vlan 10 priority 4096
spanning-tree vlan 10 priority 0*
spanning-tree vlan 10 priority 61440
12. Which nonproprietary protocol provides router redundancy for a group of routers which support IPv4 LANs?
VRRPv2*
SLB
GLBP
HSRP
13. Fill in the blank.
In FHRP operation, two or more routers are represented as a single ” virtual ” router.
14. Which three components are combined to form a bridge ID?
extended system ID*
MAC address*
port ID
IP address
cost
bridge priority*
15. What is a characteristic of a Layer 2 loop?
A switch is continually forwarding the same unicast frame.
Broadcast frames are forwarded back to the sending switch.*
Routers continually forward packets to other routers.
The Time-to-Live attribute of a frame is set to infinity.
16. Which two network design features require Spanning Tree Protocol (STP) to ensure correct network operation? (Choose two.)
redundant links between Layer 2 switches*
removing single points of failure with multiple Layer 2 switches*
link-state dynamic routing that provides redundant routes
static default routes
implementing VLANs to contain broadcasts
17. What additional information is contained in the 12-bit extended system ID of a BPDU?
MAC address
VLAN ID*
port ID
IP address
18. What is an advantage of PVST+?
PVST+ optimizes performance on the network through load sharing.*
PVST+ requires fewer CPU cycles for all the switches in the network.
PVST+ reduces bandwidth consumption compared to traditional implementations of STP that use CST.
PVST+ optimizes performance on the network through autoselection of the root bridge.
19. What is the purpose of HSRP?
It prevents malicious hosts from connecting to trunk ports.
It enables an access port to immediately transition to the forwarding state.
It prevents a rogue switch from becoming the STP root.
It provides a continuous network connection when a router fails.*
20.In which two port states does a switch learn MAC addresses and process BPDUs in a PVST network? (Choose two.)
listening
learning*
forwarding*
disabled
blocking
21.
Place the options in the following order:
Step 4
– not scored –
Step 3
Step 1
Step 2
22
Refer to the exhibit. A network engineer is troubleshooting host connectivity on a LAN that uses a first hop redundancy protocol. Which IPv4 gateway address should be configured on the host?
192.168.2.0
192.168.2.1
192.168.2.2
192.168.2.100*
23. What is the outcome of a Layer 2 broadcast storm?
CSMA/CD will cause each host to continue transmitting frames.
ARP broadcast requests are returned to the transmitting host.
Routers will take over the forwarding of frames as switches become congested.
New traffic is discarded by the switch because it is unable to be processed.*
24. What could be the effect of duplicate unicast frames arriving at a destination device due to multiple active alternative physical paths?
The number of broadcast domains increases.
The number of collision domains increases.
Application protocols malfunction.
Frame collisions increase.
When multiple alternative physical paths exist, duplicate unicast frames from a sending host will be sent to the destination. Many application protocols expect to receive only one copy of each packet, especially TCP-based protocols that use sequence number and acknowledge number to track the sequence of packets. Multiple copies of the same frame could cause application protocols to make errors in processing the packets. Broadcast storms are caused by switches flooding broadcast frames endlessly. With microsegmentation, collisions are controlled within each switch port.
25. Which STP port role is adopted by a switch port if there is no other port with a lower cost to the root bridge?
alternate
designated port
disabled port
root port
The root port is the port with the lowest cost to reach the root bridge.
26. Which is the default STP operation mode on Cisco Catalyst switches?
MST
Rapid PVST+
RSTP
MSTP
PVST+
27. What value determines the root bridge when all switches connected by trunk links have default STP configurations?
bridge priority
MAC address
VLAN ID
extended system ID
When all switches are configured with the same default bridge priority, the MAC address becomes the deciding factor for the election of the root bridge. All links on the same VLAN will also have the same extended system ID so this will not contribute to determine which switch is the root for that VLAN.
28. Which Cisco switch feature ensures that configured switch edge ports do not cause Layer 2 loops if a port is mistakenly connected to another switch?
PVST+
BPDU guard
PortFast
extended system ID
If switch access ports are configured as edge ports using PortFast, BPDUs should never be received on those ports. Cisco switches support a feature called BPDU guard. When it is enabled, BPDU guard will put an edge port in an error-disabled state if a BPDU is received by the port. This will prevent a Layer 2 loop occurring. PVST+ is an implementation of the Spanning Tree Protocol. The extended system ID is a mechanism of including VLAN ID information in the bridge ID (BID) for each VLAN.
29.
Refer to the exhibit. A network administrator configured routers R1 and R2 as part of HSRP group 1. After the routers have been reloaded, a user on Host1 complained of lack of connectivity to the Internet The network administrator issued the show standby brief command on both routers to verify the HSRP operations. In addition, the administrator observed the ARP table on Host1. Which entry should be seen in the ARP table on Host1 in order to gain connectivity to the Internet?
the virtual IP address and the virtual MAC address for the HSRP group 1
the IP address and the MAC address of R1
the virtual IP address of the HSRP group 1 and the MAC address of R1
the virtual IP address of the HSRP group 1 and the MAC address of R2
30.
31.
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