Infrastructure

Study the full QoS explanation →

A network engineer is troubleshooting an EIGRP adjacency issue between two routers. The engineer verifies that both routers have the same K-values and autonomous system number. However, the adjacency does not form. Which configuration issue is most likely the cause?

Question 3hardmultiple choice

A company is implementing QoS in a campus network. Voice traffic must be prioritized over data traffic, and all traffic should be marked at Layer 2 and Layer 3. Which combination of marking values should be used on access ports to achieve this?

Question 4easymultiple choice

Read the full wireless explanation →

An engineer needs to configure a switchport to carry traffic for multiple VLANs to a router using a single physical link. Which configuration should be applied on the switchport?

Question 5mediummultiple choice

A network engineer is deploying a new WLAN and needs to ensure that client traffic is encrypted using AES with a pre-shared key. Which security configuration should be applied to the wireless SSID?

Question 6hardmultiple choice

A network administrator is troubleshooting an issue where OSPF routes are not being learned from a neighbor. The administrator checks the OSPF configuration and sees that both routers are in the same area. The neighbor state is stuck in EXSTART. What is the most likely cause?

Question 7easymultiple choice

An engineer is configuring a new VLAN 100 on a switch. Which command must be used to create the VLAN?

Question 8mediummulti select

A company has a requirement to provide redundancy for the default gateway on a subnet. Two switches are configured with HSRP. Which two interfaces on the switches must be in the same VLAN to form the HSRP group?

Question 9hardmultiple choice

An engineer is troubleshooting a BGP routing issue. The router is not receiving routes from an eBGP neighbor. The neighbor is reachable via ping. The BGP session is established and in the Established state. What is the most likely cause?

Question 10easymultiple choice

A network administrator needs to allow SSH access to a router from the management network 192.168.1.0/24. Which configuration should be applied?

Question 11mediummulti select

Which TWO actions are valid for configuring 802.1Q trunking on a Cisco switch? (Choose two.)

Question 12hardmulti select

Which THREE conditions are required for OSPF routers to become fully adjacent? (Choose three.)

Question 13easymulti select

Which TWO methods can be used to prevent unauthorized access to the privileged EXEC mode on a Cisco router? (Choose two.)

Question 14mediummultiple choice

Based on the exhibit, what is the role of R1 on this OSPF network?

Exhibit

Refer to the exhibit.

R1# show ip ospf interface GigabitEthernet0/0
GigabitEthernet0/0 is up, line protocol is up
  Internet Address 10.1.1.1/24, Area 0
  Process ID 1, Router ID 1.1.1.1, Network Type BROADCAST, Cost: 1
  Transmit Delay is 1 sec, State BDR, Priority 1
  Designated Router (ID) 2.2.2.2, Interface address 10.1.1.2
  Backup Designated router (ID) 1.1.1.1, Interface address 10.1.1.1
  Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5

Question 15hardmultiple choice

Based on the exhibit, which traffic will be permitted outbound on GigabitEthernet0/0?

Exhibit

Refer to the exhibit.

! Running-config on R1
ip access-list extended FILTER
 permit tcp 192.168.1.0 0.0.0.255 any eq www
 permit tcp 192.168.1.0 0.0.0.255 any eq https
!
interface GigabitEthernet0/0
 ip access-group FILTER out
!

Question 16mediummultiple choice

A company has a campus network with two distribution switches (DSW1 and DSW2) connected via a Layer 2 trunk. Each distribution switch connects to two access switches. Spanning Tree Protocol (STP) is running with default settings. Recently, a network administrator added a new access switch (ASW3) and connected it to both distribution switches. After the connection, network performance degraded significantly, and users in VLAN 10 reported intermittent connectivity. The administrator checked the logs and saw multiple TCN notifications. What is the most likely cause of the issue?

Question 17hardmultiple choice

A multinational organization has a BGP-based MPLS VPN network. The CE router at a branch office is connected to two PE routers (PE1 and PE2) in the service provider network. The branch uses eBGP to exchange routes with the PEs. The network administrator notices that the branch can reach some destinations but not others. The BGP table on the CE shows routes with next-hop set to the PE loopback addresses, but those loopbacks are not reachable. The CE has a default route pointing to the PEs. What is the most likely cause of the issue?

Question 18easymulti select

Which TWO characteristics are true about the operation of Rapid PVST+? (Choose two.)

Question 19hardmultiple choice

Refer to the exhibit. R1 has two equal-cost OSPF E2 routes to 10.1.1.0/24 via two different next hops. However, when tracing to 10.1.1.1, all traffic uses the path through 10.0.1.2. What is the most likely reason?

Exhibit

Refer to the exhibit.
R1# show ip route | include 10.1.1.0
O E2 10.1.1.0/24 [110/20] via 10.0.1.2, 00:00:34, GigabitEthernet0/0
O E2 10.1.1.0/24 [110/20] via 10.0.2.2, 00:00:34, GigabitEthernet0/1
R1# show ip ospf interface GigabitEthernet0/0 | include Cost
  Process ID 1, Router ID 1.1.1.1, Network Type BROADCAST, Cost: 10
R1# show ip ospf interface GigabitEthernet0/1 | include Cost
  Process ID 1, Router ID 1.1.1.1, Network Type BROADCAST, Cost: 100
R1# traceroute 10.1.1.1 source Loopback0
Type escape sequence to abort.
Tracing the route to 10.1.1.1
  1 10.0.1.2 4 msec 4 msec 4 msec
  2 10.0.3.2 8 msec 8 msec 8 msec

Question 20mediummultiple choice

Your company has a campus network with two distribution switches (DS1 and DS2) each connected to two access switches (AS1-AS4). All switches run Rapid PVST+. The root bridge for VLAN 10 is DS1. Recently, users on AS2 (VLAN 10) report intermittent connectivity. You notice that AS2's root port for VLAN 10 is flapping between two uplinks to DS1 and DS2. The link from AS2 to DS1 is a 1 Gbps fiber, and the link to DS2 is a 1 Gbps copper. The cost of both links is 4 (default for 1 Gbps). The network administrator previously configured PortFast on all access ports but did not configure any other spanning-tree parameters. Which action should you take to stabilize the topology?

Question 21mediumdrag order

Drag and drop the steps to configure VLAN Trunking Protocol (VTP) on a Cisco switch in the correct order.

Drag steps to the numbered slots on the right, or tap a step then tap a slot.

Steps

Order

1Step 1

2Step 2

3Step 3

4Step 4

5Step 5

Question 22mediumdrag order

Drag and drop the steps for the EIGRP neighbor discovery process in the correct order.

Drag steps to the numbered slots on the right, or tap a step then tap a slot.

Steps

Order

1Step 1

2Step 2

3Step 3

4Step 4

5Step 5

Question 23mediummatching

Match each Cisco IOS command to its function.

Drag a concept onto its matching description — or click a concept then click the description.

Concepts

Matches

Displays the routing table

Displays interface status and statistics

Displays VLAN information

Displays the current configuration

Enables OSPF event debugging

Question 24mediummatching

Full Practice Test →All Objectives

Match each EIGRP term to its definition.

Drag a concept onto its matching description — or click a concept then click the description.

Concepts

Matches

Best metric to a destination

Metric advertised by neighbor

Backup route without loops

Primary route with lowest metric

Ensures loop-free backup routes

Objective 300.030% of exam

Infrastructure

350-401 Practice Questions

What this objective tests

350-401 Infrastructure — Key Topics

Infrastructure questions on this certification test your ability to deploy and manage infrastructure concepts in scenario-based situations.

Core Infrastructure concepts and how they apply in real-world cloud scenarios.
How to deploy infrastructure correctly and verify the outcome.
Troubleshooting infrastructure issues by interpreting error output and system state.
Cloud best practices and Infrastructure design trade-offs tested by this certification.

Common exam traps

Where candidates lose marks on Infrastructure

⚠Selecting the most expensive service when a simpler managed option meets the requirement.
⚠Forgetting that cloud resources must be explicitly secured — defaults are rarely secure.
⚠Choosing a global service fix when the issue is region-specific.
⚠Overlooking cost implications of cross-region data transfer in architecture questions.

350-401 Infrastructure — Practice Questions

23 questions from this objective · 30% of your 350-401 exam

Question 2mediummultiple choice

Study the full QoS explanation →

A network engineer is troubleshooting an EIGRP adjacency issue between two routers. The engineer verifies that both routers have the same K-values and autonomous system number. However, the adjacency does not form. Which configuration issue is most likely the cause?

Question 3hardmultiple choice

A company is implementing QoS in a campus network. Voice traffic must be prioritized over data traffic, and all traffic should be marked at Layer 2 and Layer 3. Which combination of marking values should be used on access ports to achieve this?

Question 4easymultiple choice

Read the full wireless explanation →

An engineer needs to configure a switchport to carry traffic for multiple VLANs to a router using a single physical link. Which configuration should be applied on the switchport?

Question 5mediummultiple choice

A network engineer is deploying a new WLAN and needs to ensure that client traffic is encrypted using AES with a pre-shared key. Which security configuration should be applied to the wireless SSID?

Question 6hardmultiple choice

A network administrator is troubleshooting an issue where OSPF routes are not being learned from a neighbor. The administrator checks the OSPF configuration and sees that both routers are in the same area. The neighbor state is stuck in EXSTART. What is the most likely cause?

Question 7easymultiple choice

An engineer is configuring a new VLAN 100 on a switch. Which command must be used to create the VLAN?

Question 8mediummulti select

A company has a requirement to provide redundancy for the default gateway on a subnet. Two switches are configured with HSRP. Which two interfaces on the switches must be in the same VLAN to form the HSRP group?

Question 9hardmultiple choice

An engineer is troubleshooting a BGP routing issue. The router is not receiving routes from an eBGP neighbor. The neighbor is reachable via ping. The BGP session is established and in the Established state. What is the most likely cause?

Question 10easymultiple choice

A network administrator needs to allow SSH access to a router from the management network 192.168.1.0/24. Which configuration should be applied?

Question 11mediummulti select

Which TWO actions are valid for configuring 802.1Q trunking on a Cisco switch? (Choose two.)

Question 12hardmulti select

Which THREE conditions are required for OSPF routers to become fully adjacent? (Choose three.)

Question 13easymulti select

Which TWO methods can be used to prevent unauthorized access to the privileged EXEC mode on a Cisco router? (Choose two.)

Question 14mediummultiple choice

Based on the exhibit, what is the role of R1 on this OSPF network?

Exhibit

Refer to the exhibit.

R1# show ip ospf interface GigabitEthernet0/0
GigabitEthernet0/0 is up, line protocol is up
  Internet Address 10.1.1.1/24, Area 0
  Process ID 1, Router ID 1.1.1.1, Network Type BROADCAST, Cost: 1
  Transmit Delay is 1 sec, State BDR, Priority 1
  Designated Router (ID) 2.2.2.2, Interface address 10.1.1.2
  Backup Designated router (ID) 1.1.1.1, Interface address 10.1.1.1
  Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5

Question 15hardmultiple choice

Based on the exhibit, which traffic will be permitted outbound on GigabitEthernet0/0?

Exhibit

Refer to the exhibit.

! Running-config on R1
ip access-list extended FILTER
 permit tcp 192.168.1.0 0.0.0.255 any eq www
 permit tcp 192.168.1.0 0.0.0.255 any eq https
!
interface GigabitEthernet0/0
 ip access-group FILTER out
!

Question 16mediummultiple choice

A company has a campus network with two distribution switches (DSW1 and DSW2) connected via a Layer 2 trunk. Each distribution switch connects to two access switches. Spanning Tree Protocol (STP) is running with default settings. Recently, a network administrator added a new access switch (ASW3) and connected it to both distribution switches. After the connection, network performance degraded significantly, and users in VLAN 10 reported intermittent connectivity. The administrator checked the logs and saw multiple TCN notifications. What is the most likely cause of the issue?

Question 17hardmultiple choice

A multinational organization has a BGP-based MPLS VPN network. The CE router at a branch office is connected to two PE routers (PE1 and PE2) in the service provider network. The branch uses eBGP to exchange routes with the PEs. The network administrator notices that the branch can reach some destinations but not others. The BGP table on the CE shows routes with next-hop set to the PE loopback addresses, but those loopbacks are not reachable. The CE has a default route pointing to the PEs. What is the most likely cause of the issue?

Question 18easymulti select

Which TWO characteristics are true about the operation of Rapid PVST+? (Choose two.)

Question 19hardmultiple choice

Refer to the exhibit. R1 has two equal-cost OSPF E2 routes to 10.1.1.0/24 via two different next hops. However, when tracing to 10.1.1.1, all traffic uses the path through 10.0.1.2. What is the most likely reason?

Exhibit

Refer to the exhibit.
R1# show ip route | include 10.1.1.0
O E2 10.1.1.0/24 [110/20] via 10.0.1.2, 00:00:34, GigabitEthernet0/0
O E2 10.1.1.0/24 [110/20] via 10.0.2.2, 00:00:34, GigabitEthernet0/1
R1# show ip ospf interface GigabitEthernet0/0 | include Cost
  Process ID 1, Router ID 1.1.1.1, Network Type BROADCAST, Cost: 10
R1# show ip ospf interface GigabitEthernet0/1 | include Cost
  Process ID 1, Router ID 1.1.1.1, Network Type BROADCAST, Cost: 100
R1# traceroute 10.1.1.1 source Loopback0
Type escape sequence to abort.
Tracing the route to 10.1.1.1
  1 10.0.1.2 4 msec 4 msec 4 msec
  2 10.0.3.2 8 msec 8 msec 8 msec

Question 20mediummultiple choice

Your company has a campus network with two distribution switches (DS1 and DS2) each connected to two access switches (AS1-AS4). All switches run Rapid PVST+. The root bridge for VLAN 10 is DS1. Recently, users on AS2 (VLAN 10) report intermittent connectivity. You notice that AS2's root port for VLAN 10 is flapping between two uplinks to DS1 and DS2. The link from AS2 to DS1 is a 1 Gbps fiber, and the link to DS2 is a 1 Gbps copper. The cost of both links is 4 (default for 1 Gbps). The network administrator previously configured PortFast on all access ports but did not configure any other spanning-tree parameters. Which action should you take to stabilize the topology?

Question 21mediumdrag order

Drag and drop the steps to configure VLAN Trunking Protocol (VTP) on a Cisco switch in the correct order.

Drag steps to the numbered slots on the right, or tap a step then tap a slot.

Steps

Order

1Step 1

2Step 2

3Step 3

4Step 4

5Step 5

Question 22mediumdrag order

Drag and drop the steps for the EIGRP neighbor discovery process in the correct order.

Drag steps to the numbered slots on the right, or tap a step then tap a slot.

Steps

Order

1Step 1

2Step 2

3Step 3

4Step 4

5Step 5

Question 23mediummatching

Match each Cisco IOS command to its function.

Drag a concept onto its matching description — or click a concept then click the description.

Concepts

Matches

Displays the routing table

Displays interface status and statistics

Displays VLAN information

Displays the current configuration

Enables OSPF event debugging

Question 24mediummatching