CCNA Practice Test 22 — 15 Questions

Question 1

A network administrator receives a report that a user on a Windows laptop cannot connect to the internet, although other devices on the same subnet are working. The administrator runs `ipconfig` on the laptop and sees an IP address of 169.254.15.22 with a subnet mask of 255.255.0.0 and no default gateway. Based on this output, what is the most likely cause of the connectivity issue?

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

Accepted Answer

The DHCP server is unreachable or not responding to the laptop's DHCP request.. The IP address 169.254.15.22 with a subnet mask of 255.255.0.0 is an Automatic Private IP Addressing (APIPA) address, which Windows assigns when a DHCP client fails to obtain a lease from a DHCP server. The absence of a default gateway confirms that the laptop cannot reach any DHCP server, as APIPA addresses are not routable and are only used for link-local communication. Therefore, the most likely cause is that the DHCP server is unreachable or not responding to the laptop's DHCP request.

Answer

The laptop's DNS server settings are incorrect.

Answer

The laptop has a static IP address configured that conflicts with another device.

Answer

The Ethernet cable is faulty or disconnected.

Question 2

A user reports that they cannot access a remote server at IP address 10.10.20.50. The user's PC has IP address 192.168.1.25/24, and the default gateway is 192.168.1.1. The user can successfully ping the default gateway and other hosts on the local subnet. However, pings to 10.10.20.50 fail, and a traceroute shows only the first hop (192.168.1.1) followed by timeouts. Which of the following is the most likely cause?

Accepted Answer

The default gateway lacks a route to the 10.10.20.0/24 network.. The user can reach local hosts and the default gateway, confirming that the PC's IP configuration and local switching are functional. The traceroute stopping at 192.168.1.1 with subsequent timeouts indicates that the default gateway receives the packets but does not know how to forward them to the 10.10.20.0/24 network. Therefore, the most likely cause is that the default gateway lacks a route to that remote subnet.

Answer

The user's PC has an incorrect subnet mask.

Answer

The remote server at 10.10.20.50 is powered off.

Answer

The user's DNS server is unreachable.

Question 3

Refer to the exhibit. A network engineer notices that on a four-link EtherChannel bundle between two switches, all traffic from a particular VLAN is being forwarded over only one physical link, while the other three links remain idle. The engineer suspects a load-balancing issue and issues the show etherchannel load-balance command, the output of which is shown. What is the most likely cause of the uneven traffic distribution?

Accepted Answer

The switch is using source‑MAC‑address load balancing, and multiple end hosts are appearing with the same source MAC address.. The output of 'show etherchannel load-balance' indicates the switch is using source-MAC-address load balancing. With this method, all frames from a given source MAC address are hashed to the same physical link. If multiple end hosts in the VLAN are actually behind a single upstream router or firewall that uses the same source MAC address for all traffic (e.g., due to proxy ARP or NAT), then all traffic from that VLAN will be pinned to one link, leaving the other three idle.

Answer

The EtherChannel is misconfigured with an LACP active/passive mode mismatch, forcing only one link to bundle.

Answer

VLAN pruning on the trunk has removed the VLAN from three of the four member interfaces.

Answer

Spanning Tree Protocol has blocked three of the four links in the EtherChannel because they form a loop.

Question 4

A packet is destined for 192.168.40.130. The routing table contains 192.168.40.0/24, 192.168.40.128/25, and 0.0.0.0/0. Which route is used?

Accepted Answer

192.168.40.128/25. The /25 route is used because it is the most specific matching prefix. In plain language, even though the /24 and the default route also technically match, the router prefers the entry that most precisely describes the destination range. Since 192.168.40.130 falls inside 192.168.40.128/25, that route wins under longest-prefix match.

This is a classic routing-table interpretation pattern. The router does not start with the default route when more specific routes exist, and it does not choose the /24 simply because it is familiar. Specificity comes first.

Answer

192.168.40.0/24

Answer

0.0.0.0/0

Answer

No route can be used because the entries overlap

Question 5

A host is configured as 192.168.100.65/26. What is the valid host range for its subnet?

Accepted Answer

192.168.100.65 to 192.168.100.126. A /26 creates blocks of 64 addresses. In plain language, the subnets in the last octet are 0–63, 64–127, 128–191, and 192–255. Because the host address is 192.168.100.65, it belongs to the 64–127 block. In that block, 192.168.100.64 is the network address and 192.168.100.127 is the broadcast address. That leaves 192.168.100.65 through 192.168.100.126 as the valid host range.

This checks whether you can identify both the subnet boundary and the usable range.

Answer

192.168.100.64 to 192.168.100.127

Answer

192.168.100.1 to 192.168.100.62

Answer

192.168.100.66 to 192.168.100.127

Question 6

Two switches should form an EtherChannel using LACP. One side is configured active and the other passive. If the port settings otherwise match, what is the expected result?

Accepted Answer

The EtherChannel should form if the other interface settings are compatible.. The EtherChannel should form successfully. In plain language, active mode initiates LACP negotiation and passive mode listens and responds. Because one side is active, the negotiation can begin and the bundle can come up as long as the underlying interface settings are compatible.

This is a standard LACP pairing. The important lesson is that active/passive works, while passive/passive usually does not. The correct answer is the one that recognizes active/passive as a valid combination.

Answer

The EtherChannel fails because both sides must be active.

Answer

the bundle forms but only in PAgP mode

Answer

only the active side attempts to bundle

Question 7

A router interface is configured with 192.0.2.97/28. What is the network address of the subnet?

Accepted Answer

192.0.2.96. A /28 uses blocks of 16 addresses. The block containing .97 runs from .96 through .111, so .96 is the network address.

Answer

192.0.2.80

Answer

192.0.2.111

Answer

192.0.2.112

Question 8

A router is configured as follows:

interface g0/1
 ip address 172.16.1.1 255.255.255.0
 ip helper-address 10.20.20.10

Hosts on 172.16.1.0/24 are not receiving addresses from the DHCP server at 10.20.20.10. The server is reachable by ping from the router.

What is the purpose of the ip helper-address command in this scenario?

Accepted Answer

It forwards certain UDP broadcasts, including DHCP requests, to a remote server. The ip helper-address command exists to solve a broadcast-boundary problem. DHCP clients begin by sending broadcast traffic because they do not yet have a valid IP configuration. Routers normally do not forward broadcasts between subnets, so if the DHCP server lives on a different network, the client request would stop at the router. The helper-address function listens for that local broadcast and relays it as unicast traffic to the remote DHCP server. In plain language, it lets a client on one VLAN ask a DHCP server on another VLAN for an address. The command is not a routing statement and it is not a DNS feature. It is a relay mechanism for broadcast-based UDP services such as DHCP.

Answer

It converts DHCP unicast replies into broadcasts on the client segment

Answer

It provides DNS resolution for DHCP clients before they receive an address

Answer

It creates a static route to the DHCP server

Question 9

An engineer applies this command on an access interface connected to a user PC: switchport port-security violation restrict. What happens if a second unauthorized MAC address appears on the port?

Accepted Answer

Frames from the unauthorized MAC are dropped and the violation is counted while the port stays up.. With restrict mode, the switch drops frames from the violating MAC, increments the violation counter, and can generate notifications. Unlike shutdown mode, the interface stays up. Unlike protect mode, the switch records the violation.

Answer

The port immediately goes err-disabled.

Answer

The switch forwards the traffic but logs a warning.

Answer

The port transitions to listening and learning states.

Question 10

An interface is configured with 10.24.7.158/27. What is the broadcast address of that subnet?

Accepted Answer

10.24.7.159. A /27 uses blocks of 32 addresses. The block containing .158 is 10.24.7.128 through 10.24.7.159, so .159 is the broadcast address.

Answer

10.24.7.191

Answer

10.24.7.127

Answer

10.24.7.160

Question 11

A controller-based WLAN uses 5 GHz in an open office. Clients keep disconnecting when users roam between APs, but signal strength remains strong. Based on the exhibit, what is the most likely problem?

Accepted Answer

A transmit power mismatch is creating asymmetric coverage around AP-3.. The APs are transmitting at much higher power than the clients, creating a coverage imbalance. Clients may hear the AP well enough to stay associated too long, while the AP cannot reliably hear the weaker client at the same cell edge. That leads to sticky-client and roaming issues even when RSSI looks strong.

Answer

The SSID must use 2.4 GHz only for roaming to work.

Answer

WPA2 cannot support roaming between APs.

Answer

The WLAN needs a different DHCP scope on each AP.

Question 12

A host cannot communicate with its default gateway. The technician uses the show arp command on the host and sees that the ARP entry for the gateway IP is incomplete. The technician has already verified that the Ethernet cable is securely connected and the switch port is active. What should the technician do next?

Accepted Answer

Check the switch port’s VLAN configuration and ensure the host and router interface are in the same VLAN.. An incomplete ARP entry for the default gateway indicates that the host sent an ARP request but never received a reply. Since the physical layer (cable and switch port) is verified as operational, the most likely cause is a Layer 2 mismatch: the host and the router interface are in different VLANs, preventing the ARP reply from reaching the host. Checking the switch port's VLAN configuration ensures both devices are in the same broadcast domain, which is required for ARP to function.

Answer

Replace the Ethernet cable between the host and the switch.

Answer

Clear the ARP cache on the host and attempt to ping the gateway again.

Answer

Check the router’s routing table for a route to the host’s subnet.

Question 13

Match each REST API method to the action it most closely represents in a typical network automation workflow.

Accepted Answer

GET retrieves data, POST creates new resources, PUT updates/replaces, PATCH partially updates, DELETE removes, and OPTIONS queries available methods.. GET retrieves data, POST creates new resources, PUT updates/replaces, PATCH partially updates, DELETE removes, and OPTIONS queries available methods. These correspond to common network automation workflows.

Answer

GET retrieves data, POST creates new resources, PUT partially updates, PATCH updates/replaces, DELETE removes, and OPTIONS queries available methods.

Answer

GET retrieves data, POST updates/replaces, PUT creates new resources, PATCH partially updates, DELETE removes, and OPTIONS queries available methods.

Answer

GET retrieves data, POST creates new resources, PUT partially updates, PATCH updates/replaces, DELETE removes, and OPTIONS queries available methods.

Question 14

After configuring a static discard route with the command 'ip route 0.0.0.0 0.0.0.0 Null0 254' on R1, a network engineer finds that traffic to destinations that are not in the routing table is still being forwarded out to the ISP instead of being dropped. What is the most likely cause?

Accepted Answer

The ISP static default route has an administrative distance of 1, which is lower than the administrative distance of 254 set for the Null0 route.. The static discard route with an administrative distance of 254 is less preferred than the ISP default route with an administrative distance of 1. Since the ISP route has a lower AD, it remains in the routing table and is used for forwarding traffic to unknown destinations, overriding the discard route. The Null0 route only becomes active if the ISP route is removed or fails, as the router always selects the route with the lowest administrative distance.

Answer

The Null0 interface is administratively shut down.

Answer

The address 0.0.0.0/0 is an invalid destination for a static route because it is not a real network.

Answer

The static discard route must include a next-hop IP address instead of specifying Null0 as the interface.

Question 15

A router has routes to 192.168.100.0/24 and 192.168.100.128/25. Which route is used for traffic to 192.168.100.140?

Accepted Answer

192.168.100.128/25. The /25 route is used because it is the most specific matching prefix. In practical terms, 192.168.100.140 falls inside the upper half of the /24, which is exactly what the 192.168.100.128/25 route describes. Even though the /24 also matches, the router always prefers the narrower route when both are valid.

This is a direct longest-prefix-match question. It reinforces that specificity is checked before broader route-source preferences matter.

Answer

192.168.100.0/24

Answer

The default route

Answer

Neither route, because the prefixes overlap