CCNA 2 Questions Flashcards
Refer to the exhibit. What will router R1 do with a packet that has a destination IPv6 address of 2001:db8:cafe:5::1?
- forward the packet out GigabitEthernet0/0
- drop the packet
- forward the packet out GigabitEthernet0/1
- forward the packet out Serial0/0/0
- forward the packet out Serial0/0/0
Explanation:
The route ::/0 is the compressed form of the 0000:0000:0000:0000:0000:0000:0000:0000/0 default route. The default route is used if a more specific route is not found in the routing table.
Refer to the exhibit. Currently router R1 uses an EIGRP route learned from Branch2 to reach the 10.10.0.0/16 network. Which floating static route would create a backup route to the 10.10.0.0/16 network in the event that the link between R1 and Branch2 goes down?
- ip route 10.10.0.0 255.255.0.0 Serial 0/0/0 100
- ip route 10.10.0.0 255.255.0.0 209.165.200.226 100
- ip route 10.10.0.0 255.255.0.0 209.165.200.225 100
- ip route 10.10.0.0 255.255.0.0 209.165.200.225 50
- ip route 10.10.0.0 255.255.0.0 209.165.200.225 100
Explanation:
A floating static route needs to have an administrative distance that is greater than the administrative distance of the active route in the routing table. Router R1 is using an EIGRP route which has an administrative distance of 90 to reach the 10.10.0.0/16 network.
To be a backup route the floating static route must have an administrative distance greater than 90 and have a next hop address corresponding to the serial interface IP address of Branch1.
Refer to the exhibit. R1 was configured with the static route command ip route 209.165.200.224 255.255.255.224 S0/0/0 and consequently users on network 172.16.0.0/16 are unable to reach resources on the Internet. How should this static route be changed to allow user traffic from the LAN to reach the Internet?
- Add an administrative distance of 254.
- Change the destination network and mask to 0.0.0.0 0.0.0.0
- Change the exit interface to S0/0/1.
- Add the next-hop neighbor address of 209.165.200.226.
- Change the destination network and mask to 0.0.0.0 0.0.0.0
Explanation: The static route on R1 has been incorrectly configured with the wrong destination network and mask. The correct destination network and mask is 0.0.0.0 0.0.0.0.
Which option shows a correctly configured IPv4 default static route?
- ip route 0.0.0.0 255.255.255.0 S0/0/0
- ip route 0.0.0.0 0.0.0.0 S0/0/0
- ip route 0.0.0.0 255.255.255.255 S0/0/0
- ip route 0.0.0.0 255.0.0.0 S0/0/0
- ip route 0.0.0.0 0.0.0.0 S0/0/0
Explanation: The static route ip route 0.0.0.0 0.0.0.0 S0/0/0 is considered a default static route and will match all destination networks.
Refer to the exhibit. Which static route command can be entered on R1 to forward traffic to the LAN connected to R2?
- ipv6 route 2001:db8:12:10::/64 S0/0/0
- ipv6 route 2001:db8:12:10::/64 S0/0/1 fe80::2
- ipv6 route 2001:db8:12:10::/64 S0/0/0 fe80::2
- ipv6 route 2001:db8:12:10::/64 S0/0/1 2001:db8:12:10::1
- ipv6 route 2001:db8:12:10::/64 S0/0/1 fe80::2
What is a method to launch a VLAN hopping attack?
- introducing a rogue switch and enabling trunking
- sending spoofed native VLAN information
- sending spoofed IP addresses from the attacking host
- flooding the switch with MAC addresses
- introducing a rogue switch and enabling trunking
A cybersecurity analyst is using the macof tool to evaluate configurations of switches deployed in the backbone network of an organization. Which type of LAN attack is the analyst targeting during this evaluation?
- VLAN hopping
- DHCP spoofing
- MAC address table overflow
- VLAN double-tagging
Explanation: Macof is a network attack tool and is mainly used to flood LAN switches with MAC addresses.
- MAC address table overflow
Explanation: Macof is a network attack tool and is mainly used to flood LAN switches with MAC addresses.
Refer to the exhibit. A network administrator is configuring a router as a DHCPv6 server. The administrator issues a show ipv6 dhcp pool command to verify the configuration. Which statement explains the reason that the number of active clients is 0?
- The default gateway address is not provided in the pool.
- No clients have communicated with the DHCPv6 server yet.
- The IPv6 DHCP pool configuration has no IPv6 address range specified.
- The state is not maintained by the DHCPv6 server under stateless DHCPv6 operation.
- The state is not maintained by the DHCPv6 server under stateless DHCPv6 operation.
Explanation:
Under the stateless DHCPv6 configuration, indicated by the command ipv6 nd other-config-flag, the DHCPv6 server does not maintain the state information, because client IPv6 addresses are not managed by the DHCP server.
Because the clients will configure their IPv6 addresses by combining the prefix/prefix-length and a self-generated interface ID, the ipv6 dhcp pool configuration does not need to specify the valid IPv6 address range. And because clients will use the link-local address of the router interface as the default gateway address, the default gateway address is not necessary.
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 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
- the virtual IP address and the virtual MAC address for the HSRP group 1
Explanation: Hosts will send an ARP request to the default gateway which is the virtual IP address. ARP replies from the HSRP routers contain the virtual MAC address. The host ARP tables will contain a mapping of the virtual IP to the virtual MAC.
– the IP address and the MAC address of R1
Match the forwarding characteristic to its type. (Not all options are used.)
Which statement is correct about how a Layer 2 switch determines how to forward frames?
- Frame forwarding decisions are based on MAC address and port mappings in the CAM table.
- Only frames with a broadcast destination address are forwarded out all active switch ports.
- Cut-through frame forwarding ensures that invalid frames are always dropped.
- Frame forwarding decisions are based on MAC address and port mappings in the CAM table.
Explanation:
Cut-through frame forwarding reads up to only the first 22 bytes of a frame, which excludes the frame check sequence and thus invalid frames may be forwarded. In addition to broadcast frames, frames with a destination MAC address that is not in the CAM are also flooded out all active ports. Unicast frames are not always forwarded. Received frames with a destination MAC address that is associated with the switch port on which it is received are not forwarded because the destination exists on the network segment connected to that port.
Which statement describes a result after multiple Cisco LAN switches are interconnected?
- The broadcast domain expands to all switches.
- One collision domain exists per switch.
- There is one broadcast domain and one collision domain per switch.
- Frame collisions increase on the segments connecting the switches.
- Unicast frames are always forwarded regardless of the destination MAC address.
- The broadcast domain expands to all switches.
Explanation:
In Cisco LAN switches, the micro-segmentation makes it possible for each port to represent a separate segment and thus each switch port represents a separate collision domain. This fact will not change when multiple switches are interconnected. However, LAN switches do not filter broadcast frames. A broadcast frame is flooded to all ports. Interconnected switches form one big broadcast domain.
Match the link state to the interface and protocol status. (Not all options are used.)
Refer to the exhibit. How is a frame sent from PCA forwarded to PCC if the MAC address table on switch SW1 is empty?
- SW1 forwards the frame directly to SW2. SW2 floods the frame to all ports connected to SW2, excluding the port through which the frame entered the switch.
- SW1 floods the frame on all ports on the switch, excluding the interconnected port to switch SW2 and the port through which the frame entered the switch.
- SW1 floods the frame on all ports on SW1, excluding the port through which the frame entered the switch.
- SW1 drops the frame because it does not know the destination MAC address.
- SW1 floods the frame on all ports on SW1, excluding the port through which the frame entered the switch.
Explanation:
When a switch powers on, the MAC address table is empty. The switch builds the MAC address table by examining the source MAC address of incoming frames. The switch forwards based on the destination MAC address found in the frame header. If a switch has no entries in the MAC address table or if the destination MAC address is not in the switch table, the switch will forward the frame out all ports except the port that brought the frame into the switch.
An administrator is trying to remove configurations from a switch. After using the command erase startup-config and reloading the switch, the administrator finds that VLANs 10 and 100 still exist on the switch. Why were these VLANs not removed?
- Because these VLANs are stored in a file that is called vlan.dat that is located in flash memory, this file must be manually deleted.
- These VLANs cannot be deleted unless the switch is in VTP client mode.
- These VLANs are default VLANs that cannot be removed.
- These VLANs can only be removed from the switch by using the no vlan 10 and no vlan 100 commands.
- Because these VLANs are stored in a file that is called vlan.dat that is located in flash memory, this file must be manually deleted.
Explanation: Standard range VLANs (1-1005) are stored in a file that is called vlan.dat that is located in flash memory. Erasing the startup configuration and reloading a switch does not automatically remove these VLANs. The vlan.dat file must be manually deleted from flash memory and then the switch must be reloaded.
Match the description to the correct VLAN type. (Not all options are used.)
Explanation:
A data VLAN is configured to carry user-generated traffic. A default VLAN is the VLAN where all switch ports belong after the initial boot up of a switch loading the default configuration.
A native VLAN is assigned to an 802.1Q trunk port, and untagged traffic is placed on it.
A management VLAN is any VLAN that is configured to access the management capabilities of a switch. An IP address and subnet mask are assigned to it, allowing the switch to be managed via HTTP, Telnet, SSH, or SNMP.
Refer to the exhibit. A network administrator has connected two switches together using EtherChannel technology. If STP is running, what will be the end result?
- STP will block one of the redundant links.
- The switches will load balance and utilize both EtherChannels to forward packets.
- The resulting loop will create a broadcast storm.
- Both port channels will shutdown.
- STP will block one of the redundant links.
Explanation:
Cisco switches support two protocols for negotiating a channel between two switches: LACP and PAgP. PAgP is Cisco-proprietary. In the topology shown, the switches are connected to each other using redundant links. By default, STP is enabled on switch devices. STP will block redundant links to prevent loops.
What is a secure configuration option for remote access to a network device?
- Configure an ACL and apply it to the VTY lines.
- Configure 802.1x.
- Configure SSH.
- Configure Telnet.
- Configure SSH.
Which wireless encryption method is the most secure?
- WPA2 with AES
- WPA2 with TKIP
- WEP
- WPA
- WPA2 with AES
After attaching four PCs to the switch ports, configuring the SSID and setting authentication properties for a small office network, a technician successfully tests the connectivity of all PCs that are connected to the switch and WLAN. A firewall is then configured on the device prior to connecting it to the Internet. What type of network device includes all of the described features?
- firewall appliance
- wireless router
- switch
- standalone wireless access point
- wireless router
Refer to the exhibit. Host A has sent a packet to host B. What will be the source MAC and IP addresses on the packet when it arrives at host B?
- Source MAC: 00E0.FE91.7799
Source IP: 10.1.1.10 - Source MAC: 00E0.FE10.17A3
Source IP: 10.1.1.10 - Source MAC: 00E0.FE10.17A3
Source IP: 192.168.1.1 - Source MAC: 00E0.FE91.7799
Source IP: 10.1.1.1 - Source MAC: 00E0.FE91.7799
Source IP: 192.168.1.1
- Source MAC: 00E0.FE91.7799
Source IP: 10.1.1.10
Explanation:
As a packet traverses the network, the Layer 2 addresses will change at every hop as the packet is de-encapsulated and re-encapsulated, but the Layer 3 addresses will remain the same.
Refer to the exhibit. In addition to static routes directing traffic to networks 10.10.0.0/16 and 10.20.0.0/16, Router HQ is also configured with the following command:
- Packets that are received from the Internet will be forwarded to one of the LANs connected to R1 or R2.
- Packets with a destination network that is not 10.10.0.0/16 or is not 10.20.0.0/16 or is not a directly connected network will be forwarded to the Internet.
- Packets from the 10.10.0.0/16 network will be forwarded to network 10.20.0.0/16, and packets from the 10.20.0.0/16 network will be forwarded to network 10.10.0.0/16.
- Packets that are destined for networks that are not in the routing table of HQ will be dropped.
- Packets with a destination network that is not 10.10.0.0/16 or is not 10.20.0.0/16 or is not a directly connected network will be forwarded to the Internet.
What protocol or technology disables redundant paths to eliminate Layer 2 loops?
- VTP
- STP
- EtherChannel
- DTP
- STP
Refer to the exhibit. Based on the exhibited configuration and output, why is VLAN 99 missing?
- because VLAN 99 is not a valid management VLAN
- because there is a cabling problem on VLAN 99
- because VLAN 1 is up and there can only be one management VLAN on the switch
- because VLAN 99 has not yet been created
- because VLAN 99 has not yet been created
Which two VTP modes allow for the creation, modification, and deletion of VLANs on the local switch? (Choose two.)
- client
- master
- distribution
- slave
- server
- transparent
- server
- transparent
Which three steps should be taken before moving a Cisco switch to a new VTP management domain? (Choose three.)
- Configure the switch with the name of the new management domain.
- Reset the VTP counters to allow the switch to synchronize with the other switches in the domain.
- Configure the VTP server in the domain to recognize the BID of the new switch.
- Download the VTP database from the VTP server in the new domain.
- Select the correct VTP mode and version.
- Reboot the switch.
- Configure the switch with the name of the new management domain.
- Select the correct VTP mode and version.
- Reboot the switch.
Explanation:
When adding a new switch to a VTP domain, it is critical to configure the switch with a new domain name, the correct VTP mode, VTP version number, and password. A switch with a higher revision number can propagate invalid VLANs and erase valid VLANs thus preventing connectivity for multiple devices on the valid VLANs.
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 can only be determined if PortFast has been configured.
- Link types are determined automatically.
- Link types must be configured with specific port configuration commands.
- Link types are determined automatically.
Explanation:
When Rapid PVST+ is being implemented, link types are automatically determined but can be specified manually. Link types can be either point-to-point, shared, or edge.
Refer to the exhibit. All the displayed switches are Cisco 2960 switches with the same default priority and operating at the same bandwidth. Which three ports will be STP designated ports? (Choose three.)
- fa0/9
- fa0/13
- fa0/10
- fa0/20
- fa0/21
- fa0/11
- fa0/13
- fa0/10
- fa0/21
How will a router handle static routing differently if Cisco Express Forwarding is disabled?
- It will not perform recursive lookups.
- Ethernet multiaccess interfaces will require fully specified static routes to avoid routing inconsistencies.
- Static routes that use an exit interface will be unnecessary.
- Serial point-to-point interfaces will require fully specified static routes to avoid routing inconsistencies.
- Ethernet multiaccess interfaces will require fully specified static routes to avoid routing inconsistencies.
Explanation:
In most platforms running IOS 12.0 or later, Cisco Express Forwarding is enabled by default. Cisco Express Forwarding eliminates the need for the recursive lookup. If Cisco Express Forwarding is disabled, multiaccess network interfaces require fully specified static routes in order to avoid inconsistencies in their routing tables.
Point-to-point interfaces do not have this problem, because multiple end points are not present. With or without Cisco Express Forwarding enabled, using an exit interface when configuring a static route is a viable option.
Compared with dynamic routes, what are two advantages of using static routes on a router? (Choose two.)
- They improve network security.
- They take less time to converge when the network topology changes.
- They improve the efficiency of discovering neighboring networks.
- They use fewer router resources.
Explanation: Static routes are manually configured on a router. Static routes are not automatically updated and must be manually reconfigured if the network topology changes. Thus static routing improves network security because it does not make route updates among neighboring routers. Static routes also improve resource efficiency by using less bandwidth, and no CPU cycles are used to calculate and communicate routes.
- They improve network security.
- They use fewer router resources.
Explanation: Static routes are manually configured on a router. Static routes are not automatically updated and must be manually reconfigured if the network topology changes. Thus static routing improves network security because it does not make route updates among neighboring routers.
Static routes also improve resource efficiency by using less bandwidth, and no CPU cycles are used to calculate and communicate routes.
Refer to the exhibit. Which route was configured as a static route to a specific network using the next-hop address?
- S 10.17.2.0/24 [1/0] via 10.16.2.2
- S 0.0.0.0/0 [1/0] via 10.16.2.2
- S 10.17.2.0/24 is directly connected, Serial 0/0/0
- C 10.16.2.0/24 is directly connected, Serial0/0/0
Explanation: The C in a routing table indicates an interface that is up and has an IP address assigned. The S in a routing table signifies that a route was installed using the ip route command. Two of the routing table entries shown are static routes to a specific destination (the 192.168.2.0 network). The entry that has the S denoting a static route and [1/0] was configured using the next-hop address. The other entry (S 192.168.2.0/24 is directly connected, Serial 0/0/0) is a static route configured using the exit interface. The entry with the 0.0.0.0 route is a default static route which is used to send packets to any destination network that is not specifically listed in the routing table.
- S 10.17.2.0/24 [1/0] via 10.16.2.2
Explanation:
The C in a routing table indicates an interface that is up and has an IP address assigned. The S in a routing table signifies that a route was installed using the ip route command.
Two of the routing table entries shown are static routes to a specific destination (the 192.168.2.0 network). The entry that has the S denoting a static route and [1/0] was configured using the next-hop address.
The other entry (S 192.168.2.0/24 is directly connected, Serial 0/0/0) is a static route configured using the exit interface. The entry with the 0.0.0.0 route is a default static route which is used to send packets to any destination network that is not specifically listed in the routing table.
What is the effect of entering the spanning-tree portfast configuration command on a switch?
- It disables an unused port.
- It disables all trunk ports.
- It enables portfast on a specific switch interface.
- It checks the source L2 address in the Ethernet header against the sender L2 address in the ARP body.
- It enables portfast on a specific switch interface.
What is the IPv6 prefix that is used for link-local addresses?
- FF01::/8
- 2001::/3
*FC00::/7
- FE80::/10
- FE80::/10
Explanation: The IPv6 link-local prefix is FE80::/10 and is used to create a link-local IPv6 address on an interface.
Which two statements are characteristics of routed ports on a multilayer switch? (Choose two.)
- In a switched network, they are mostly configured between switches at the core and distribution layers.
- The interface vlan command has to be entered to create a VLAN on routed ports.
- They support subinterfaces, like interfaces on the Cisco IOS routers.
- They are used for point-to-multipoint links.
- They are not associated with a particular VLAN.
- In a switched network, they are mostly configured between switches at the core and distribution layers.
- They are not associated with a particular VLAN.
Successful inter-VLAN routing has been operating on a network with multiple VLANs across multiple switches for some time. When an inter-switch trunk link fails and Spanning Tree Protocol brings up a backup trunk link, it is reported that hosts on two VLANs can access some, but not all the network resources that could be accessed previously. Hosts on all other VLANS do not have this problem. What is the most likely cause of this problem?
- The protected edge port function on the backup trunk interfaces has been disabled.
- The allowed VLANs on the backup link were not configured correctly.
- Dynamic Trunking Protocol on the link has failed.
*Inter-VLAN routing also failed when the trunk link failed.
- The protected edge port function on the backup trunk interfaces has been disabled.
Which command will start the process to bundle two physical interfaces to create an EtherChannel group via LACP?
- interface port-channel 2
- channel-group 1 mode desirable
- interface range GigabitEthernet 0/4 – 5
- channel-group 2 mode auto
- interface range GigabitEthernet 0/4 – 5
What action takes place when a frame entering a switch has a multicast destination MAC address?
- The switch will forward the frame out all ports except the incoming port.
- The switch forwards the frame out of the specified port.
- The switch adds a MAC address table entry mapping for the destination MAC address and the ingress port.
- The switch replaces the old entry and uses the more current port.
Explanation: If the destination MAC address is a broadcast or a multicast, the frame is also flooded out all ports except the incoming port.
- The switch will forward the frame out all ports except the incoming port.
Explanation:
If the destination MAC address is a broadcast or a multicast, the frame is also flooded out all ports except the incoming port.
A junior technician was adding a route to a LAN router. A traceroute to a device on the new network revealed a wrong path and unreachable status. What should be done or checked?
- Verify that there is not a default route in any of the edge router routing tables.
- Check the configuration on the floating static route and adjust the AD.
- Create a floating static route to that network.
- Check the configuration of the exit interface on the new static route.
- Check the configuration of the exit interface on the new static route.
Select the three PAgP channel establishment modes. (Choose three.)
- auto
- default
- passive
- desirable
- extended
- on
- auto
*desirable
- on
A static route has been configured on a router. However, the destination network no longer exists. What should an administrator do to remove the static route from the routing table?
- Remove the route using the no ip route command.
- Change the administrative distance for that route.
- Change the routing metric for that route.
- Nothing. The static route will go away on its own.
- Remove the route using the no ip route command.
Refer to the exhibit. What can be concluded about the configuration shown on R1?
- R1 is configured as a DHCPv4 relay agent.
- R1 is operating as a DHCPv4 server.
- R1 will broadcast DHCPv4 requests on behalf of local DHCPv4 clients.
- R1 will send a message to a local DHCPv4 client to contact a DHCPv4 server at 10.10.10.8.
- R1 is configured as a DHCPv4 relay agent.
Match the step to each switch boot sequence description. (Not all options are used.)
Explanation: The steps are:
1. execute POST
2. load the boot loader from ROM
3. CPU register initializations
4. flash file system initialization
5. load the IOS
6. transfer switch control to the IOS
Refer to the exhibit. R1 has been configured as shown. However, PC1 is not able to receive an IPv4 address. What is the problem?
- The ip helper-address command was applied on the wrong interface.
- R1 is not configured as a DHCPv4 server.
- A DHCP server must be installed on the same LAN as the host that is receiving the IP address.
- The ip address dhcp command was not issued on the interface Gi0/1.
- The ip helper-address command was applied on the wrong interface.
Explanation:
The ip helper-address command has to be applied on interface Gi0/0. This command must be present on the interface of the LAN that contains the DHCPv4 client PC1 and must be directed to the correct DHCPv4 server.
What two default wireless router settings can affect network security? (Choose two.)
- The SSID is broadcast.
- MAC address filtering is enabled.
- WEP encryption is enabled.
- The wireless channel is automatically selected.
- The SSID is broadcast.
- A well-known administrator password is set.
Explanation:
Default settings on wireless routers often include broadcasting the SSID and using a well-known administrative password. Both of these pose a security risk to wireless networks.
WEP encryption and MAC address filtering are not set by default. The automatic selection of the wireless channel poses no security risks.
What is the common term given to SNMP log messages that are generated by network devices and sent to the SNMP server?
- traps
- acknowledgments
- auditing
- warnings
- traps
A network administrator is adding a new WLAN on a Cisco 3500 series WLC. Which tab should the administrator use to create a new VLAN interface to be used for the new WLAN?
- WIRELESS
- MANAGEMENT
- CONTROLLER
- WLANs
- CONTROLLER
A network administrator is configuring a WLAN. Why would the administrator change the default DHCP IPv4 addresses on an AP?
- to restrict access to the WLAN by authorized, authenticated users only
- to monitor the operation of the wireless network
- to reduce outsiders intercepting data or accessing the wireless network by using a well-known address range
- to reduce the risk of interference by external devices such as microwave ovens
- to reduce outsiders intercepting data or accessing the wireless network by using a well-known address range
Which two functions are performed by a WLC when using split media access control (MAC)? (Choose two.)
- packet acknowledgments and retransmissions
- frame queuing and packet prioritization
- beacons and probe responses
- frame translation to other protocols
- association and re-association of roaming clients
- frame translation to other protocols
- association and re-association of roaming clients
On what switch ports should BPDU guard be enabled to enhance STP stability?
- all PortFast-enabled ports
- only ports that are elected as designated ports
- only ports that attach to a neighboring switch
- all trunk ports that are not root ports
- all PortFast-enabled ports
Which network attack is mitigated by enabling BPDU guard?
- rogue switches on a network
- CAM table overflow attacks
- MAC address spoofing
- rogue DHCP servers on a network
- rogue switches on a network
Explanation:
There are several recommended STP stability mechanisms to help mitigate STP manipulation attacks:
PortFast – used to immediately bring an interface configured as an access or trunk port to the forwarding state from a blocking state.
Applied to all end-user ports.
BPDU guard – immediately error-disables a port that receives a BPDU. Applied to all end-user ports.The receipt of BPDUs may be part of an unauthorized attempt to add a switch to the network.
Root guard – prevents a switch from becoming the root switch. Applied to all ports where the root switch should not be located.
Loop guard – detects unidirectional links to prevent alternate or root ports from becoming designated ports. Applied to all ports that are or can become non-designated.
Why is DHCP snooping required when using the Dynamic ARP Inspection feature?
- It relies on the settings of trusted and untrusted ports set by DHCP snooping.
- It uses the MAC address table to verify the default gateway IP address.
- It redirects ARP requests to the DHCP server for verification.
- It uses the MAC-address-to-IP-address binding database to validate an ARP packet.
- It uses the MAC-address-to-IP-address binding database to validate an ARP packet.
Explanation:
DAI relies on DHCP snooping. DHCP snooping listens to DHCP message exchanges and builds a bindings database of valid tuples (MAC address, IP address, VLAN interface).
When DAI is enabled, the switch drops ARP packet if the sender MAC address and sender IP address do not match an entry in the DHCP snooping bindings database. However, it can be overcome through static mappings.
Static mappings are useful when hosts configure static IP addresses, DHCP snooping cannot be run, or other switches in the network do not run dynamic ARP inspection. A static mapping associates an IP address to a MAC address on a VLAN.
Refer to the exhibit. Router R1 has an OSPF neighbor relationship with the ISP router over the 192.168.0.32 network. The 192.168.0.36 network link should serve as a backup when the OSPF link goes down. The floating static route command ip route 0.0.0.0 0.0.0.0 S0/0/1 100 was issued on R1 and now traffic is using the backup link even when the OSPF link is up and functioning.
Which change should be made to the static route command so that traffic will only use the OSPF link when it is up?
- Change the administrative distance to 120.
- Add the next hop neighbor address of 192.168.0.36.
- Change the destination network to 192.168.0.34.
- Change the administrative distance to 1.
- Change the administrative distance to 120.
Explanation:
The problem with the current floating static route is that the administrative distance is set too low. The administrative distance will need to be higher than that of OSPF, which is 110, so that the router will only use the OSPF link when it is up.
Refer to the exhibit. What is the metric to forward a data packet with the IPv6 destination address 2001:DB8:ACAD:E:240:BFF:FED4:9DD2?
- 90
- 128
- 2170112
- 2681856
- 2682112
- 3193856
- 2682112
Explain: The IPv6 destination address 2001:DB8:ACAD:E:240:BFF:FED4:9DD2 belongs to the network of 2001:DB8:ACAD:E::/64. In the routing table, the route to forward the packet has Serial 0/0/1 as an exit interface and 2682112 as the cost.
A network administrator is configuring a new Cisco switch for remote management access. Which three items must be configured on the switch for the task? (Choose three.)
- IP address
- VTP domain
- vty lines
- default VLAN
- default gateway
- loopback address
- IP address
- vty lines
- default gateway
Explain: To enable the remote management access, the Cisco switch must be configured with an IP address and a default gateway. In addition, vty lines must configured to enable either Telnet or SSH connections. A loopback address, default VLAN, and VTP domain configurations are not necessary for the purpose of remote switch management.
Refer to the exhibit. Which statement shown in the output allows router R1 to respond to stateless DHCPv6 requests?
- ipv6 nd other-config-flag
- prefix-delegation 2001:DB8:8::/48 00030001000E84244E70
- ipv6 dhcp server LAN1
- ipv6 unicast-routing
- dns-server 2001:DB8:8::8
- ipv6 nd other-config-flag
Explain:
The interface command ipv6 nd other-config-flag allows RA messages to be sent on this interface, indicating that additional information is available from a stateless DHCPv6 server.
Refer to the exhibit. A Layer 3 switch routes for three VLANs and connects to a router for Internet connectivity. Which two configurations would be applied to the switch? (Choose two.)
- (config)# interface gigabitethernet1/1
(config-if)# switchport mode trunk - (config)# interface gigabitethernet 1/1
(config-if)# no switchport
(config-if)# ip address 192.168.1.2 255.255.255.252 - (config)# interface vlan 1
(config-if)# ip address 192.168.1.2 255.255.255.0
(config-if)# no shutdown - (config)# interface fastethernet0/4
(config-if)# switchport mode trunk - (config)# ip routing
- (config)# interface gigabitethernet 1/1
(config-if)# no switchport
(config-if)# ip address 192.168.1.2 255.255.255.252 - (config)# ip routing
. A technician is troubleshooting a slow WLAN and decides to use the split-the-traffic approach. Which two parameters would have to be configured to do this? (Choose two.)
- Configure the 5 GHz band for streaming multimedia and time sensitive traffic.
- Configure the security mode to WPA Personal TKIP/AES for one network and WPA2 Personal AES for the other network
- Configure the 2.4 GHz band for basic internet traffic that is not time sensitive.
- Configure the security mode to WPA Personal TKIP/AES for both networks.
- Configure a common SSID for both split networks.
- Configure the 5 GHz band for streaming multimedia and time sensitive traffic.
- Configure the 2.4 GHz band for basic internet traffic that is not time sensitive.
A company has just switched to a new ISP. The ISP has completed and checked the connection from its site to the company. However, employees at the company are not able to access the internet. What should be done or checked?
- Verify that the static route to the server is present in the routing table.
- Check the configuration on the floating static route and adjust the AD.
- Ensure that the old default route has been removed from the company edge routers.
- Create a floating static route to that network.
- Ensure that the old default route has been removed from the company edge routers.
Which information does a switch use to populate the MAC address table?
- the destination MAC address and the incoming port
- the destination MAC address and the outgoing port
- the source and destination MAC addresses and the incoming port
- the source and destination MAC addresses and the outgoing port
- the source MAC address and the incoming port
- the source MAC address and the outgoing port
- the source MAC address and the incoming port
Explain: To maintain the MAC address table, the switch uses the source MAC address of the incoming packets and the port that the packets enter. The destination address is used to select the outgoing port.
Refer to the exhibit. A network administrator is reviewing the configuration of switch S1. Which protocol has been implemented to group multiple physical ports into one logical link?
- PAgP
- DTP
- LACP
- STP
- PAgP
Which type of static route is configured with a greater administrative distance to provide a backup route to a route learned from a dynamic routing protocol?
- floating static route
- default static route
- summary static route
- standard static route
Explain: There are four basic types of static routes. Floating static routes are backup routes that are placed into the routing table if a primary route is lost. A summary static route aggregates several routes into one, reducing the of the routing table. Standard static routes are manually entered routes into the routing table. Default static routes create a gateway of last resort.
- floating static route
Explain:
There are four basic types of static routes. Floating static routes are backup routes that are placed into the routing table if a primary route is lost. A summary static route aggregates several routes into one, reducing the of the routing table. Standard static routes are manually entered routes into the routing table. Default static routes create a gateway of last resort.
What action takes place when a frame entering a switch has a unicast destination MAC address appearing in the MAC address table?
- The switch updates the refresh timer for the entry.
- The switch forwards the frame out of the specified port.
- The switch purges the entire MAC address table.
- The switch replaces the old entry and uses the more current port.
- The switch forwards the frame out of the specified port.
The exhibit shows two PCs called PC A and PC B, two routes called R1 and R2, and two switches. PC A has the address 172.16.1.1/24 and is connected to a switch and into an interface on R1 that has the IP address 172.16.1.254. PC B has the address 172.16.2.1/24 and is connected to a switch that is connected to another interface on R1 with the IP address 172.16.2.254.
The serial interface on R1 has the address 172.16.3.1 and is connected to the serial interface on R2 that has the address
172.16.3.2/24. R2 is connected to the internet cloud. Which command will create a static route on R2 in order to reach PC B?
- R2(config)# ip route 172.16.2.1 255.255.255.0 172.16.3.1
- R2(config)# ip route 172.16.2.0 255.255.255.0 172.16.2.254
- R2(config)# ip route 172.16.2.0 255.255.255.0 172.16.3.1
- R2(config)# ip route 172.16.3.0 255.255.255.0 172.16.2.254
R2(config)# ip route 172.16.2.0 255.255.255.0 172.16.3.1
Explain: The correct syntax is:
router(config)# ip route destination-network destination-mask {next-hop-ip-address | exit-interface}
If the local exit interface instead of the next-hop IP address is used then the route will be displayed as a directly connected route instead of a static route in the routing table. Because the network to be reached is 172.16.2.0 and the next-hop IP address is 172.16.3.1, the command is R2(config)# ip route 172.16.2.0 255.255.255.0 172.16.3.1
What protocol or technology allows data to transmit over redundant switch links?
- EtherChannel
- DTP
- STP
- VTP
- STP
Refer to the exhibit. Which three hosts will receive ARP requests from host A, assuming that port Fa0/4 on both switches is configured to carry traffic for multiple VLANs? (Choose three.)
- host B
- host C
- host D
- host E
- host F
- host G
- host C
- host D
- host F
Explain:
ARP requests are sent out as broadcasts. That means the ARP request is sent only throughout a specific VLAN. VLAN 1 hosts will only hear ARP requests from hosts on VLAN 1. VLAN 2 hosts will only hear ARP requests from hosts on VLAN 2.
Refer to the exhibit. The network administrator configures both switches as displayed. However, host C is unable to ping host D and host E is unable to ping host F. What action should the administrator take to enable this communication?
- Associate hosts A and B with
VLAN 10 instead of VLAN 1. - Configure either trunk port in the dynamic desirable mode.
- Include a router in the topology.
- Remove the native VLAN from the trunk.
- Add the switchport nonegotiate command to the configuration of SW2.
- Configure either trunk port in the dynamic desirable mode.
What is the effect of entering the shutdown configuration command on a switch?
- It enables BPDU guard on a specific port.
- It disables an unused port.
- It enables portfast on a specific switch interface.
- It disables DTP on a non-trunking interface.
- It disables an unused port.
What would be the primary reason an attacker would launch a MAC address overflow attack?
- so that the switch stops forwarding traffic
- so that legitimate hosts cannot obtain a MAC address
- so that the attacker can see frames that are destined for other hosts
- so that the attacker can execute arbitrary code on the switch
- so that the attacker can see frames that are destined for other hosts
Refer to the exhibit. Which trunk link will not forward any traffic after the root bridge election process is complete?
- Trunk1
- Trunk2
- Trunk3
- Trunk4
- Trunk2
Refer to the exhibit. After attempting to enter the configuration that is shown in router RTA, an administrator receives an error and users on VLAN 20 report that they are unable to reach users on VLAN 30. What is causing the problem?
- There is no address on Fa0/0 to use as a default gateway.
- RTA is using the same subnet for VLAN 20 and VLAN 30.
- Dot1q does not support subinterfaces.
- The no shutdown command should have been issued on Fa0/0.20 and Fa0/0.30.
- RTA is using the same subnet for VLAN 20 and VLAN 30.
Refer to the exhibit. What are the possible port roles for ports A, B, C, and D in this RSTP-enabled network?
- alternate, designated, root, root
- designated, alternate, root, root
- alternate, root, designated, root
- designated, root, alternate, root
- alternate, designated, root, root
Explanation:
Because S1 is the root bridge, B is a designated port, and C and D root ports. RSTP supports a new port type, alternate port in discarding state, that can be port A in this scenario.
Refer to the exhibit. Which static route would an IT technician enter to create a backup route to the 172.16.1.0 network that is only used if the primary RIP learned route fails?
- ip route 172.16.1.0 255.255.255.0 s0/0/0
- ip route 172.16.1.0 255.255.255.0 s0/0/0 121
- ip route 172.16.1.0 255.255.255.0 s0/0/0 111
- ip route 172.16.1.0 255.255.255.0 s0/0/0 91
- ip route 172.16.1.0 255.255.255.0 s0/0/0 121
Explanation:
A backup static route is called a floating static route. A floating static route has an administrative distance greater than the administrative distance of another static route or dynamic route.
Refer to the exhibit. Which destination MAC address is used when frames are sent from the workstation to the default gateway?
- MAC address of the virtual router
- MAC address of the standby router
- MAC addresses of both the forwarding and standby routers
- MAC address of the forwarding router
- MAC address of the virtual router
Explanation:
The IP address of the virtual router acts as the default gateway for all the workstations. Therefore, the MAC address that is returned by the Address Resolution Protocol to the workstation will be the MAC address of the virtual router.
Match the purpose with its DHCP message type. (Not all options are used.)
Refer to the exhibit. A network administrator is verifying the configuration of inter-VLAN routing. Users complain that PC2 cannot communicate with PC1. Based on the output, what is the possible cause of the problem?
- Gi0/0 is not configured as a trunk port.
- The command interface GigabitEthernet0/0.5 was entered incorrectly.
- There is no IP address configured on the interface Gi0/0.
- The no shutdown command is not entered on subinterfaces.
- The encapsulation dot1Q 5 command contains the wrong VLAN.
- The encapsulation dot1Q 5 command contains the wrong VLAN.
Refer to the exhibit. A network administrator is configuring inter-VLAN routing on a network. For now, only one VLAN is being used, but more will be added soon. What is the missing parameter that is shown as the highlighted question mark in the graphic?
- It identifies the sub-interface.
- It identifies the VLAN number.
- It identifies the native VLAN number.
- It identifies the type of encapsulation that is used.
- It identifies the number of hosts that are allowed on the interface.
- It identifies the VLAN number.
Match each DHCP message type with its description. (Not all options are used.)
Explanation: Place the options in the following order:
- a client initiating a message to find a DHCP server – DHCPDISCOVER
- a DHCP server responding to the initial request by a client – DHCPOFFER
- the client accepting the IP address provided by the DHCP server – DHCPREQUEST
- the DHCP server confirming that the lease has been accepted – DHCPACK
Refer to the exhibit. If the IP addresses of the default gateway router and the DNS server are correct, what is the configuration problem?
- The DNS server and the default gateway router should be in the same subnet.
- The IP address of the default gateway router is not contained in the excluded address list.
- The default-router and dns-server commands need to be configured with subnet masks.
- The IP address of the DNS server is not contained in the excluded address list.
- The IP address of the default gateway router is not contained in the excluded address list.
Explanation:
In this configuration, the excluded address list should include the address that is assigned to the default gateway router. So the command should be ip dhcp excluded-address 192.168.10.1 192.168.10.9.
Refer to the exhibit. A network administrator has added a new subnet to the network and needs hosts on that subnet to receive IPv4 addresses from the DHCPv4 server.
What two commands will allow hosts on the new subnet to receive addresses from the DHCP4 server? (Choose two.)
- R1(config-if)# ip helper-address 10.2.0.250
- R1(config)# interface G0/1
- R1(config)# interface G0/0
- R2(config-if)# ip helper-address 10.2.0.250
- R2(config)# interface G0/0
- R1(config-if)# ip helper-address 10.1.0.254
- R1(config-if)# ip helper-address 10.2.0.250
- R1(config)# interface G0/0
Explanation:
You need the router interface that is connected to the new subnet and the dhcp server address.
The ip helper-address command is used to configure a router to be a DHCPv4 relay.
The command should be placed on the interface facing the DHCPv4 clients. When the command is applied on the router interface, the interface will receive DHCPv4 broadcast messages and forward them as unicast to the IP address of the DHCPv4 server.
Match the DHCP message types to the order of the DHCPv4 process. (Not all options are used.)
Refer to the exhibit. The network administrator is configuring the port security feature on switch SWC. The administrator issued the command show port-security interface fa 0/2 to verify the configuration. What can be concluded from the output that is shown? (Choose three.)
- Three security violations have been detected on this interface.
- This port is currently up.
- The port is configured as a trunk link.
- Security violations will cause this port to shut down immediately.
- There is no device currently connected to this port.
- The switch port mode for this interface is access mode.
- This port is currently up.
- Security violations will cause this port to shut down immediately.
- The switch port mode for this interface is access mode.
Explanation:
Because the security violation count is at 0, no violation has occurred. The system shows that 3 MAC addresses are allowed on port fa0/2, but only one has been configured and no sticky MAC addresses have been learned. The port is up because of the port status of secure-up. The violation mode is what happens when an unauthorized device is attached to the port. A port must be in access mode in order to activate and use port security.
Refer to the exhibit. Which two conclusions can be drawn from the output? (Choose two.)
- The EtherChannel is down.
- The port channel ID is 2.
- The port channel is a Layer 3 channel.
- The bundle is fully operational.
- The load-balancing method used is source port to destination port.
- The EtherChannel is down.
- The port channel ID is 2.
Match the step number to the sequence of stages that occur during the HSRP failover process. (Not all options are used.)
Refer to the exhibit. A network engineer is configuring IPv6 routing on the network. Which command issued on router HQ will configure a default route to the Internet to forward packets to an IPv6 destination network that is not listed in the routing table?
- ipv6 route ::/0 serial 0/0/0
- ip route 0.0.0.0 0.0.0.0 serial 0/1/1
- ipv6 route ::1/0 serial 0/1/1
- ipv6 route ::/0 serial 0/1/1
- ipv6 route ::/0 serial 0/1/1
Refer to the exhibit. A network administrator configures R1 for inter-VLAN routing between VLAN 10 and VLAN 20. However, the devices in VLAN 10 and VLAN 20 cannot communicate. Based on the configuration in the exhibit, what is a possible cause for the problem?
A. The port Gi0/0 should be configured as trunk port.
B. The encapsulation is misconfigured on a subinterface.
C. A no shutdown command should be added in each subinterface configuration.
D. The command interface gigabitEthernet 0/0.1 is wrong.
D. The command interface gigabitEthernet 0/0.1 is wrong.
Refer to the exhibit. A network administrator is configuring the router R1 for IPv6 address assignment. Based on the partial configuration, which IPv6 global unicast address assignment scheme does the administrator intend to implement?
- stateful
- stateless
- manual configuration
- SLAAC
- Stateful
Refer to the exhibit. Consider that the main power has just been restored. PC3 issues a broadcast IPv4 DHCP request. To which port will SW1 forward this request?
- to Fa0/1, Fa0/2, and Fa0/3 only
- to Fa0/1, Fa0/2, Fa0/3, and Fa0/4
- to Fa0/1 only
- to Fa0/1, Fa0/2, and Fa0/4 only
- to Fa0/1 and Fa0/2 only
- to Fa0/1, Fa0/2, and Fa0/3 only
Refer to the exhibit. PC-A and PC-B are both in VLAN 60. PC-A is unable to communicate with PC-B. What is the problem?
*The native VLAN should be VLAN 60.
*The native VLAN is being pruned from the link.
*The trunk has been configured with the switchport nonegotiate command.
*The VLAN that is used by PC-A is not in the list of allowed VLANs on the trunk.
*The VLAN that is used by PC-A is not in the list of allowed VLANs on the trunk.
Explanation:
Because PC-A and PC-B are connected to different switches, traffic between them must flow over the trunk link. Trunks can be configured so that they only allow traffic for particular VLANs to cross the link. In this scenario, VLAN 60, the VLAN that is associated with PC-A and PC-B, has not been allowed across the link, as shown by the output of show interfaces trunk.
Refer to the exhibit. An administrator is attempting to install an IPv6 static route on router R1 to reach the network attached to router R2. After the static route command is entered, connectivity to the network is still failing. What error has been made in the static route configuration?
*The next hop address is incorrect.
*The interface is incorrect.
*The destination network is incorrect.
*The network prefix is incorrect.
*The interface is incorrect.
Explanation:
In this example the interface in the static route is incorrect. The interface should be the exit interface on R1, which is s0/0/0.
