CCNA Mock Exam 83 — 25 Questions

Question 1

A junior administrator is configuring a Cisco switch port that connects to a conference room wall jack. The requirement is that only the first device that connects may use the port, and if any other MAC address is seen, the port should immediately go into an error-disabled state and require manual recovery. Which port security configuration should be applied?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

switchport port-security violation shutdown. Port security shutdown violation mode err-disables the interface when a MAC address that exceeds the allowed set is detected. Because the scenario requires only the first device to be permitted and immediate disabling upon any other MAC address, the default maximum of 1 combined with shutdown violation is appropriate. Manual recovery is then needed to bring the port back into service.

Answer

switchport port-security maximum 2

Answer

switchport port-security violation protect

Answer

switchport port-security violation restrict

Question 2

An engineer uses the Cisco Catalyst Center (formerly DNA Center) Intent API to retrieve a list of network devices. The API response is paginated, returning only 50 devices by default even though the inventory holds several hundred. The engineer needs the complete inventory in a single automation run. Which action should the engineer take?

Accepted Answer

Increase the value of the 'limit' query parameter and adjust the 'offset' parameter across successive requests until all devices are retrieved.. The Intent API limits how many records a single response carries, so a complete inventory requires paging. Raising the page size with the limit parameter and advancing through results with the offset parameter lets an automation script collect every device before processing. Authentication headers and media-type headers shape access and representation, not result volume.

Answer

Add the 'X-Auth-Token' header with a longer expiry so the controller stops truncating the response.

Answer

Change the HTTP method from GET to POST so the controller returns the entire collection in a single response body.

Answer

Set the 'Accept' header to 'application/yang-data+json' so the controller returns the full YANG-modeled dataset without pagination.

Question 3

A network administrator is configuring a router to forward all unknown IPv4 traffic to the next-hop address 192.168.1.1. Which command correctly creates this default static route?

Accepted Answer

ip route 0.0.0.0 0.0.0.0 192.168.1.1. The correct command to configure an IPv4 default static route is 'ip route 0.0.0.0 0.0.0.0 192.168.1.1'. The destination 0.0.0.0 with mask 0.0.0.0 matches any IPv4 address, and the next hop is specified as 192.168.1.1. This route is used when no more specific route matches the destination. Other options either use an invalid mask, add unnecessary parameters, or have incorrect syntax.

Answer

ip route 0.0.0.0 0.0.0.0 192.168.1.1 name DEFAULT

Answer

ip route 0.0.0.0 255.255.255.255 192.168.1.1

Answer

ip route 0.0.0.0 0.0.0.0 192.168.1.1 1

Question 4

A network administrator is configuring VLANs on a Cisco Catalyst switch. The design requires that VLAN 10 traffic and VLAN 20 traffic share the same physical uplink to a router, but each VLAN must remain logically separate at Layer 2. The router interface is configured with 802.1Q encapsulation. Which statement correctly describes how the router will process frames arriving from both VLANs on that single physical interface?

Accepted Answer

The router will use subinterfaces, each associated with a VLAN ID, to terminate the 802.1Q tags and route between the VLANs.. Router-on-a-stick uses a single physical router interface configured with 802.1Q encapsulation and multiple subinterfaces, each mapped to a VLAN ID. The router terminates the VLAN tags, assigns each subinterface an IP address as the default gateway for that VLAN, and routes traffic between VLANs at Layer 3. This meets the requirement of sharing one uplink while maintaining logical separation of VLAN 10 and VLAN 20.

Answer

The router will forward tagged frames between VLAN 10 and VLAN 20 at Layer 2, acting as a transparent bridge for those VLANs.

Answer

The router will strip the 802.1Q tag and route traffic between VLAN 10 and VLAN 20 without requiring any subinterfaces.

Answer

The router will require a separate physical interface for each VLAN because 802.1Q does not support multiple VLANs on one link.

Question 5

A network engineer is configuring OSPFv2 on a Cisco router. The router is connected to two different OSPF areas: Area 0 and Area 1. The engineer wants to summarize the routes from Area 1 into Area 0. Which router type is required to perform this summarization?

Accepted Answer

Area Border Router (ABR). An Area Border Router (ABR) is required to summarize routes between OSPF areas. It connects to multiple areas, including Area 0, and can use the area range command to summarize routes from one area into another. Internal routers, backbone routers, and ASBRs do not perform this function.

Answer

Autonomous System Boundary Router (ASBR)

Answer

Internal router

Answer

Backbone router

Question 6

A router is running OSPFv2 and has learned multiple routes to the same destination. You need to ensure that OSPF installs the route with the lowest cost into the routing table. Which two statements about OSPF path selection are true? (Choose two.)

Accepted Answer

OSPF uses cost as the metric, which is calculated based on bandwidth.. OSPF uses cost as its metric, derived from interface bandwidth, and it prefers the lowest total cost path. When multiple paths have the same cost, OSPF performs equal-cost load balancing by default. The other statements are incorrect because OSPF does not use hop count, does not prefer higher cost, and does not require manual metric configuration.

Answer

OSPF uses hop count as its metric to determine the best path.

Answer

OSPF requires manual configuration of metrics on each interface to function.

Answer

OSPF selects the path with the highest cost to avoid congestion.

Question 7

A technician is connecting a new Cisco switch to an existing switch using a copper cable. The link between the two switches must carry traffic for multiple VLANs. Which command must be configured on the interface connecting to the other switch to allow multiple VLANs to traverse the link?

Accepted Answer

switchport mode trunk. To carry traffic for multiple VLANs over a single inter-switch link, the interface must be configured as a trunk. The command switchport mode trunk sets the interface to permanent trunking mode, allowing 802.1Q-tagged frames for multiple VLANs to traverse the link. Other commands like nonegotiate or allowed vlan list are supplementary and only apply after trunk mode is enabled.

Answer

switchport mode access

Answer

switchport nonegotiate

Answer

switchport trunk allowed vlan all

Question 8

A small office uses a Cisco router as its DHCP server for the 192.168.50.0/24 LAN. The administrator wants client devices to resolve internal hostnames such as printer.office.local without contacting an external resolver first. Which DHCP option should be configured on the router to supply the internal DNS server address to clients?

Accepted Answer

Option 6, the DNS server. DHCP option 6 is the standardized field that conveys DNS server addresses to clients. When the router's DHCP pool includes the internal resolver's address under option 6, clients automatically direct their queries there. The default gateway, domain name, and NTP server options serve routing, suffix, and time synchronization purposes respectively, so none of them provides the DNS resolver address required by the scenario.

Answer

Option 42, the NTP server

Answer

Option 3, the default gateway

Answer

Option 15, the domain name

Question 9

A network administrator is configuring a Cisco switch to support a new voice VLAN. The design requires that IP phones and PCs share the same switch port, with voice traffic tagged and data traffic untagged. Which two commands are required on the switch port to support this configuration? (Choose two.)

Accepted Answer

switchport voice vlan 50. To support an IP phone and PC on the same switch port, the port must be in access mode for the data VLAN and have a voice VLAN configured. The switchport mode access command ensures untagged data traffic, while switchport voice vlan 50 instructs the phone to tag voice traffic with VLAN 50. Together, these commands enable the required separation of voice and data traffic.

Answer

switchport mode trunk

Answer

switchport access vlan 10

Answer

switchport trunk encapsulation dot1q

Question 10

A network administrator is configuring a site-to-site IPsec VPN between two Cisco routers. The administrator wants to ensure that the VPN traffic is protected by both encryption and integrity checking. Which combination of IPsec protocols should be used?

Accepted Answer

ESP for both encryption and integrity. ESP (Encapsulating Security Payload) is the IPsec protocol that can provide both encryption and integrity. It supports confidentiality through encryption algorithms and integrity through authentication algorithms. AH (Authentication Header) provides only integrity and authentication, not encryption. Therefore, to meet the requirement of both encryption and integrity, ESP alone is sufficient and is the standard choice for site-to-site VPNs.

Answer

ESP for encryption and AH for integrity

Answer

AH for both encryption and integrity

Answer

AH for encryption and ESP for integrity

Question 11

A network engineer is configuring a floating static route on a Cisco router to provide backup connectivity to a remote network 172.16.0.0/16. The primary route is learned via OSPF. The engineer wants the static route to be used only if the OSPF route is lost. Which command should be used?

Accepted Answer

ip route 172.16.0.0 255.255.0.0 192.168.1.2 200. A floating static route is a static route with a higher administrative distance than the primary route, so it remains inactive until the primary route is lost. For OSPF with a default distance of 110, the static route must have a distance greater than 110, such as 200. When the OSPF route disappears, the static route is installed and used.

Answer

ip route 172.16.0.0 255.255.0.0 192.168.1.2 110

Answer

ip route 172.16.0.0 255.255.0.0 192.168.1.2 255

Answer

ip route 172.16.0.0 255.255.0.0 192.168.1.2 90

Question 12

A network administrator is troubleshooting a switch that is receiving DHCPDISCOVER messages from a client on VLAN 20, but the DHCP server on a different subnet never sees those requests. The interface VLAN 20 has the address 10.20.0.1/24, and the DHCP server address is 10.99.0.10. Which command should be applied to enable the switch to forward these requests to the server?

Accepted Answer

ip helper-address 10.99.0.10. DHCP relay is configured with the ip helper-address command on the interface facing the clients, which unicasts their DHCP broadcasts to the specified server and sets the gateway address so the server can match the correct scope. Without it, the broadcast stays on the local subnet and the remote server never receives the request.

Answer

ip dhcp pool VLAN20

Answer

ip forward-protocol udp 67

Answer

ip dhcp relay information option

Question 13

A junior administrator is configuring a Cisco switch port that connects to a conference room wall jack. The requirement is that only the first device that connects may use the port, and if any other MAC address is seen, the port should immediately go into an error-disabled state and require manual recovery. Which port security configuration should be applied?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

ip helper-address 192.168.100.50. The router must act as a DHCP relay agent because clients broadcast on the local segment while the server sits on a different subnet. Configuring the LAN interface with ip helper-address pointing to the server converts those broadcasts into unicasts toward 192.168.100.50, enabling address assignment without placing a DHCP server on every LAN.

Answer

ip forward-protocol udp 192.168.100.50

Answer

ip dhcp relay 192.168.100.50

Answer

ip dhcp pool LAN

Question 14

A network administrator is configuring OSPFv2 on a Cisco router. The router is connected to two different areas: Area 0 and Area 1. The administrator wants to summarize the routes from Area 1 into Area 0. Which two statements are true about OSPF inter-area route summarization? (Choose two.)

Accepted Answer

Summarization is configured on the ABR using the area range command.. Inter-area route summarization in OSPF is performed on an Area Border Router (ABR) using the area range command. The ABR advertises a single Type 3 summary LSA for the summarized prefix into other areas, reducing the number of LSAs and routing table entries. It does not require a stub area, and the summary-address command is for external summarization on an ASBR.

Answer

Summarization is configured using the summary-address command on the ABR.

Answer

Summarization requires the area to be a stub area.

Answer

Summarization can only be configured on an ASBR.

Question 15

A network administrator is configuring DHCP snooping on a Cisco Catalyst switch. The switch has a trunk port Gi1/0/24 connecting to another switch, and several access ports connecting to end-user PCs. The administrator issues the commands 'ip dhcp snooping', 'ip dhcp snooping vlan 10', and then configures interface Gi1/0/24 with 'ip dhcp snooping trust'. A PC connected to Gi1/0/5 (an untrusted port) sends a DHCPDISCOVER. What will the switch do with this DHCPDISCOVER message?

Accepted Answer

Forward the DHCPDISCOVER to trusted ports only, and drop any DHCPOFFER received on untrusted ports.. When DHCP snooping is enabled on a VLAN, switch ports are untrusted by default. Client DHCP messages such as DHCPDISCOVER are allowed from untrusted ports and forwarded toward trusted ports. Server messages such as DHCPOFFER, DHCPACK, and DHCPNAK are dropped if received on untrusted ports. Trusting the uplink port allows legitimate server replies to enter the switch while blocking rogue DHCP servers on access ports.

Answer

Drop the DHCPDISCOVER because only trusted ports can send DHCP messages.

Answer

Forward the DHCPDISCOVER to all ports in VLAN 10, including untrusted access ports.

Answer

Convert the untrusted port to a trusted port automatically after receiving the first DHCPDISCOVER.

Question 16

A campus switch has VLANs 10, 20, and 30 configured. Port GigabitEthernet0/5 connects to a server that must send and receive traffic for all three VLANs, and the server's NIC supports 802.1Q tagging. The administrator wants the server to handle VLAN tagging itself. Which configuration on GigabitEthernet0/5 is appropriate?

Accepted Answer

switchport mode trunk and switchport trunk allowed vlan 10,20,30. When a server NIC performs 802.1Q tagging itself, the switch port must be a trunk so tagged frames for multiple VLANs can pass. Restricting the allowed VLAN list to 10, 20, and 30 limits unnecessary traffic and matches the requirement. A static trunk avoids DTP negotiation issues with a server that does not run DTP.

Answer

switchport mode access and switchport access vlan 10

Answer

switchport mode trunk, switchport trunk native vlan 10, and switchport access vlan 20

Answer

switchport mode dynamic desirable and switchport trunk allowed vlan 10,20,30

Question 17

A junior administrator is asked to configure a Cisco router interface with the IPv4 address 10.1.1.1 and a subnet mask of 255.255.255.0 so it can route traffic for the 10.1.1.0/24 network. Which command correctly assigns this address to the interface?

Accepted Answer

ip address 10.1.1.1 255.255.255.0. Cisco IOS interface configuration uses the ip address command with the address and a dotted-decimal subnet mask, so ip address 10.1.1.1 255.255.255.0 is correct. Slash notation, the ipv4 keyword, and an extra mask keyword are all invalid in this context. Getting the exact syntax right is essential because a rejected command leaves the interface unaddressed and unable to route for the 10.1.1.0/24 network.

Answer

ipv4 address 10.1.1.1 255.255.255.0

Answer

ip address 10.1.1.1 mask 255.255.255.0

Answer

ip address 10.1.1.1/24

Question 18

You are configuring a Cisco router that connects to an ISP through two different providers. The primary path is learned dynamically through OSPF, and the backup path is a static route pointing to a next-hop of 203.0.113.1. You need the static route to remain in the routing table only when the OSPF-learned default route is unavailable. Which configuration should you apply?

Accepted Answer

ip route 0.0.0.0 0.0.0.0 203.0.113.1 250. A floating static route is created by configuring a static route with an administrative distance higher than that of the dynamic routing protocol providing the primary route. OSPF's default administrative distance is 110, so a static route with a distance of 250 will not be installed while the OSPF route exists. When OSPF loses the route, the static route becomes active and provides backup connectivity.

Answer

ip route 0.0.0.0 0.0.0.0 203.0.113.1 110

Answer

ip route 0.0.0.0 0.0.0.0 203.0.113.1 90

Answer

ip route 0.0.0.0 0.0.0.0 203.0.113.1 permanent

Question 19

A router has the following routes in its routing table: a static route to 10.1.1.0/24 with administrative distance 1, an OSPF route to 10.1.1.0/24 with administrative distance 110, and an EIGRP route to 10.1.1.0/24 with administrative distance 90. A packet arrives destined for 10.1.1.50. Which route will the router use to forward the packet?

Accepted Answer

The static route. Administrative distance is used to select the best route when multiple routing sources provide a route to the same destination. The static route has the lowest administrative distance (1), so it is preferred over EIGRP (90) and OSPF (110). The packet will be forwarded using the static route.

Answer

The EIGRP route

Answer

The OSPF route

Answer

The router will load-balance between all three routes

Question 20

A network team deploys an AI-assisted operations platform that analyzes streaming telemetry from switches and routers. The team wants the platform to detect degradation before users report trouble. Which two data characteristics most directly improve the platform's ability to detect anomalies early? (Choose two.)

Accepted Answer

High-frequency, model-driven telemetry pushed from devices at short intervals.. Early anomaly detection depends on data that is both frequent and time-aligned. Short-interval, model-driven telemetry supplies the granular time series needed to see subtle degradation, while synchronized timestamps let the platform correlate events across devices. Coarse polling, manual gating, and single-device collection all starve the analytics engine of the density and context it needs.

Answer

Polling each device every 30 minutes with SNMP for CPU and memory counters.

Answer

Storing telemetry only after manual review by a network engineer.

Answer

Collecting data from a single core switch to reduce pipeline complexity.