Cisco Certified Network Associate 試験
Question No : 1
An engineer is asked to protect unused ports that are configured in the default VLAN on a switch .
Which two steps will fulfill the request? (Choose two)
Question No : 2
Refer to the exhibit.
The show ip ospf interface command has been executed on R1 .
How is OSPF configured?
From the output we can see there are Designated Router & Backup Designated Router for this OSPF domain so this is a broadcast network (point-to-point and point-to multipoint networks do not elect DR & BDR) -> Answer B is not correct.
By default, the timers on a broadcast network (Ethernet, point-to-point and point-to-multipoint) are 10 seconds hello and 40 seconds dead (therefore answer C is correct). The timers on a non- broadcast network are 30 seconds hello 120 seconds dead.
From the line “Neighbor Count is 3”, we learn there are four OSPF routers in this OSPF domain -> Answer D is not correct.
Question No : 3
An engineer configured an OSPF neighbor as a designated router .
Which state verifies the designated router is in the proper mode?
Question No : 4
Which command is used to specify the delay time in seconds for LLDP to initialize on any interface?
+ lldp holdtime seconds: Specify the amount of time a receiving device should hold the information from your device before discarding it
+ lldp reinit delay: Specify the delay time in seconds for LLDP to initialize on an interface
+ lldp timer rate: Set the sending frequency of LLDP updates in seconds
Reference: Click here
Question No : 5
Refer to Exhibit .
Which action do the switches take on the trunk link?
The trunk still forms with mismatched native VLANs and the traffic can actually flow between mismatched switches. But it is absolutely necessary that the native VLANs on both ends of a trunk link match; otherwise a native VLAN mismatch occurs, causing the two VLANs to effectively merge.
For example with the above configuration, SW1 would send untagged frames for VLAN 999. SW2 receives them but would think they are for VLAN 99 so we can say these two VLANs are merged.
Question No : 6
Which two actions influence the EIGRP route selection process? (Choose two)
The reported distance (or advertised distance) is the cost from the neighbor to the destination. It is calculated from the router advertising the route to the network. For example in the topology below, suppose router A & B are exchanging their routing tables for the first time. Router B says "Hey, the best metric (cost) from me to IOWA is 50 and the metric from you to IOWA is 90" and advertises it to router A.
Router A considers the first metric (50) as the Advertised distance. The second metric (90), which is from NEVADA to IOWA (through IDAHO), is called the Feasible distance.
The reported distance is calculated in the same way of calculating the metric. By default (K1 = 1, K2 = 0, K3 = 1, K4 = 0, K5 = 0), the metric is calculated as follows:
-> Answer A is not correct.
Feasible successor is the backup route. To be a feasible successor, the route must have an Advertised distance (AD) less than the Feasible distance (FD) of the current successor route -> Answer B is correct. Feasible distance (FD): The sum of the AD plus the cost between the local router and the next- hop router. The router must calculate the FD of all paths to choose the best path to put into the routing table.
Note: Although the new CCNA exam does not have EIGRP topic but you should learn the basic knowledge of this routing protocol.
Question No : 7
Which two values or settings must be entered when configuring a new WLAN in the Cisco Wireless LAN Controller GUI? (Choose two)
Question No : 8
Which IPv6 address block sends packets to a group address rather than a single address?
FF00::/8 is used for IPv6 multicast and this is the IPv6 type of address the question wants to ask.
FE80::/10 range is used for link-local addresses. Link-local addresses only used for communications within the local subnetwork (automatic address configuration, neighbor discovery, router discovery, and by many routing protocols). It is only valid on the current subnet.
It is usually created dynamically using a link-local prefix of FE80::/10 and a 64-bit interface identifier (based on 48-bit MAC address).
Question No : 9
Refer to the exhibit .
Which route does R1 select for traffic that is destined to 192 168.16.2?
The destination IP addresses match all four entries in the routing table but the 192.168.16.0/27 has the longest prefix so it will be chosen. This is called the "longest prefix match" rule.
Question No : 10
Refer to the exhibit.
An engineer configured NAT translations and has verified that the configuration is correct .
Which IP address is the source IP?
Question No : 11
Refer to the exhibit .
What is the effect of this configuration?
Dynamic ARP inspection is an ingress security feature; it does not perform any egress checking.
Question No : 12
What is the default behavior of a Layer 2 switch when a frame with an unknown destination MAC address is received?
If the destination MAC address is not in the CAM table (unknown destination MAC address), the switch sends the frame out all other ports that are in the same VLAN as the received frame. This is called flooding. It does not flood the frame out the same port on which the frame was received.
Question No : 13
What is the primary effect of the spanning-tree portfast command?
Question No : 14
Router A learns the same route from two different neighbors, one of the neighbor routers is an OSPF neighbor and the other is an EIGRP neighbor .
What is the administrative distance of the route that will be installed in the routing table?
The Administrative distance (AD) of EIGRP is 90 while the AD of OSPF is 110 so EIGRP route will be chosen to install into the routing table.
Question No : 15
What are two reasons that cause late collisions to increment on an Ethernet interface? (Choose two)
A late collision is defined as any collision that occurs after the first 512 bits (or 64th byte) of the frame have been transmitted. The usual possible causes are full-duplex/half-duplex mismatch, exceeded Ethernet cable length limits, or defective hardware such as incorrect cabling, noncompliant number of hubs in the network, or a bad NIC.
Late collisions should never occur in a properly designed Ethernet network. They usually occur when Ethernet cables are too long or when there are too many repeaters in the network.
Reference: Click here