Cisco CCNA 200-301 802.1Q Trunks and Interswitch Connectivity Practice Test

Topic 13 focuses on 802.1Q Trunks and Interswitch Connectivity for the Cisco Certified Network Associate (CCNA) certification and the 200-301 exam, using Cisco networking and Cisco IOS concepts where relevant. For broader exam preparation, review the Cisco CCNA 200-301 Exam Dumps page. Each question includes a concise explanation of the correct answer and the technical reason the other choices are incorrect.

Question 1

Which Ethernet VLAN tagging standard commonly is used on switch trunks?

1. Subinterface encapsulation
2. Allowed VLAN list
3. show interfaces trunk
4. 802.1Q

Correct Answer: D

 

Correct Answer

Answer D is correct because the selected answer describes the Ethernet VLAN tagging standard commonly used on switch trunks.

Incorrect Answers

Answer A is incorrect because the “Subinterface encapsulation” option describes a different concept: Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

Answer B is incorrect because the “Allowed VLAN list” option describes a different concept: the set of VLANs permitted to traverse a trunk link.

Answer C is incorrect because the “show interfaces trunk” option describes a different concept: a Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

 

Question 2

Which Layer 2 interface can carry traffic for multiple VLANs?

1. Subinterface encapsulation
2. 802.1Q tag
3. Trunk port
4. Native VLAN

Correct Answer: C

 

Correct Answer

Answer C is correct because the selected answer describes a Layer 2 interface that can carry traffic for multiple VLANs.

Incorrect Answers

Answer A is incorrect because the “Subinterface encapsulation” option describes a different concept: Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

Answer B is incorrect because the “802.1Q tag” option describes a different concept: a field inserted into an Ethernet frame to identify its VLAN on a tagged trunk.

Answer D is incorrect because the “Native VLAN” option describes a different concept: the VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.

 

Question 3

What is a field inserted into an Ethernet frame to identify its VLAN on a tagged trunk?

802. 802.1Q
803. 802.1Q tag
804. Native VLAN
805. Trunk port

Correct Answer: B

 

Correct Answer

Answer B is correct because the selected answer describes a field inserted into an Ethernet frame to identify its VLAN on a tagged trunk.

Incorrect Answers

Answer A is incorrect because the “802.1Q” option describes a different concept: the Ethernet VLAN tagging standard commonly used on switch trunks.

Answer C is incorrect because the “Native VLAN” option describes a different concept: the VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.

Answer D is incorrect because the “Trunk port” option describes a different concept: a Layer 2 interface that can carry traffic for multiple VLANs.

 

Question 4

By default, which VLAN on an 802.1Q trunk carries frames without an 802.1Q tag?

1. Allowed VLAN list
2. show interfaces trunk
3. Native VLAN
4. 802.1Q tag

Correct Answer: C

 

Correct Answer

Answer C is correct because the selected answer describes the VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.

Incorrect Answers

Answer A is incorrect because the “Allowed VLAN list” option describes a different concept: the set of VLANs permitted to traverse a trunk link.

Answer B is incorrect because the “show interfaces trunk” option describes a different concept: a Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

Answer D is incorrect because the “802.1Q tag” option describes a different concept: a field inserted into an Ethernet frame to identify its VLAN on a tagged trunk.

 

Question 5

What is the set of VLANs permitted to traverse a trunk link?

1. Subinterface encapsulation
2. Router-on-a-stick
3. Native VLAN
4. Allowed VLAN list

Correct Answer: D

 

Correct Answer

Answer D is correct because the selected answer describes the set of VLANs permitted to traverse a trunk link.

Incorrect Answers

Answer A is incorrect because the “Subinterface encapsulation” option describes a different concept: Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

Answer B is incorrect because the “Router-on-a-stick” option describes a different concept: an inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces.

Answer C is incorrect because the “Native VLAN” option describes a different concept: the VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.

 

Question 6

Which Cisco IOS command statically configures a Layer 2 switch port as a trunk?

1. Trunk port
2. 802.1Q tag
3. switchport mode trunk
4. Allowed VLAN list

Correct Answer: C

 

Correct Answer

Answer C is correct because the selected answer describes a Cisco IOS command that statically configures a Layer 2 switch port as a trunk.

Incorrect Answers

Answer A is incorrect because the “Trunk port” option describes a different concept: a Layer 2 interface that can carry traffic for multiple VLANs.

Answer B is incorrect because the “802.1Q tag” option describes a different concept: a field inserted into an Ethernet frame to identify its VLAN on a tagged trunk.

Answer D is incorrect because the “Allowed VLAN list” option describes a different concept: the set of VLANs permitted to traverse a trunk link.

 

Question 7

Which Cisco IOS command is used to verify trunk state, native VLAN, and allowed/forwarding VLAN information?

802. 802.1Q
803. show interfaces trunk
804. Trunk port
805. Router-on-a-stick

Correct Answer: B

 

Correct Answer

Answer B is correct because the selected answer describes a Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

Incorrect Answers

Answer A is incorrect because the “802.1Q” option describes a different concept: the Ethernet VLAN tagging standard commonly used on switch trunks.

Answer C is incorrect because the “Trunk port” option describes a different concept: a Layer 2 interface that can carry traffic for multiple VLANs.

Answer D is incorrect because the “Router-on-a-stick” option describes a different concept: an inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces.

 

Question 8

What is a condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems?

1. Native VLAN mismatch
2. Allowed VLAN list
3. 802.1Q tag
4. show interfaces trunk

Correct Answer: A

 

Correct Answer

Answer A is correct because the selected answer describes a condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.

Incorrect Answers

Answer B is incorrect because the “Allowed VLAN list” option describes a different concept: the set of VLANs permitted to traverse a trunk link.

Answer C is incorrect because the “802.1Q tag” option describes a different concept: a field inserted into an Ethernet frame to identify its VLAN on a tagged trunk.

Answer D is incorrect because the “show interfaces trunk” option describes a different concept: a Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

 

Question 9

Which inter-VLAN routing design uses one physical router interface with multiple 802.1Q subinterfaces?

1. Router-on-a-stick
2. 802.1Q
3. Subinterface encapsulation
4. Trunk port

Correct Answer: A

 

Correct Answer

Answer A is correct because the selected answer describes an inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces.

Incorrect Answers

Answer B is incorrect because the “802.1Q” option describes a different concept: the Ethernet VLAN tagging standard commonly used on switch trunks.

Answer C is incorrect because the “Subinterface encapsulation” option describes a different concept: Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

Answer D is incorrect because the “Trunk port” option describes a different concept: a Layer 2 interface that can carry traffic for multiple VLANs.

 

Question 10

Which term describes router configuration that associates a logical subinterface with an 802.1Q VLAN ID?

1. Trunk port
2. Allowed VLAN list
3. Router-on-a-stick
4. Subinterface encapsulation

Correct Answer: D

 

Correct Answer

Answer D is correct because it describes router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

Incorrect Answers

Answer A is incorrect because the “Trunk port” option describes a different concept: a Layer 2 interface that can carry traffic for multiple VLANs.

Answer B is incorrect because the “Allowed VLAN list” option describes a different concept: the set of VLANs permitted to traverse a trunk link.

Answer C is incorrect because the “Router-on-a-stick” option describes a different concept: an inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces.

 

Question 11

For 802.1Q, which statement is accurate?

1. A Cisco IOS command that statically configures a Layer 2 switch port as a trunk.
2. The Ethernet VLAN tagging standard commonly used on switch trunks.
3. The set of VLANs permitted to traverse a trunk link.
4. A Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

Correct Answer: B

 

Correct Answer

Answer B is correct because it accurately defines 802.1Q. The matching definition is: The Ethernet VLAN tagging standard commonly used on switch trunks.

Incorrect Answers

Answer A is incorrect because the “switchport mode trunk” option describes a different concept: a Cisco IOS command that statically configures a Layer 2 switch port as a trunk.

Answer C is incorrect because the “Allowed VLAN list” option describes a different concept: the set of VLANs permitted to traverse a trunk link.

Answer D is incorrect because the “show interfaces trunk” option describes a different concept: a Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

 

Question 12

For Trunk port, which statement is accurate?

1. The Ethernet VLAN tagging standard commonly used on switch trunks.
2. A Cisco IOS command that statically configures a Layer 2 switch port as a trunk.
3. A Layer 2 interface that can carry traffic for multiple VLANs.
4. The set of VLANs permitted to traverse a trunk link.

Correct Answer: C

 

Correct Answer

Answer C is correct because the choice accurately describes Trunk port: A Layer 2 interface that can carry traffic for multiple VLANs.

Incorrect Answers

Answer A is incorrect because the “802.1Q” option describes a different concept: the Ethernet VLAN tagging standard commonly used on switch trunks.

Answer B is incorrect because the “switchport mode trunk” option describes a different concept: a Cisco IOS command that statically configures a Layer 2 switch port as a trunk.

Answer D is incorrect because the “Allowed VLAN list” option describes a different concept: the set of VLANs permitted to traverse a trunk link.

 

Question 13

For 802.1Q tag, which statement is accurate?

802. The VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.
803. A field inserted into an Ethernet frame to identify its VLAN on a tagged trunk.
804. A Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.
805. A condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.

Correct Answer: B

 

Correct Answer

Answer B is correct because the selected answer describes a field inserted into an Ethernet frame to identify its VLAN on a tagged trunk.

Incorrect Answers

Answer A is incorrect because the “Native VLAN” option describes a different concept: the VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.

Answer C is incorrect because the “show interfaces trunk” option describes a different concept: a Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

Answer D is incorrect because the “Native VLAN mismatch” option describes a different concept: a condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.

 

Question 14

For Native VLAN, which statement is accurate?

802. Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.
803. The VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.
804. The Ethernet VLAN tagging standard commonly used on switch trunks.
805. An inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces.

Correct Answer: B

 

Correct Answer

Answer B is correct because the selected answer describes the VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.

Incorrect Answers

Answer A is incorrect because the “Subinterface encapsulation” option describes a different concept: Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

Answer C is incorrect because the “802.1Q” option describes a different concept: the Ethernet VLAN tagging standard commonly used on switch trunks.

Answer D is incorrect because the “Router-on-a-stick” option describes a different concept: an inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces.

 

Question 15

For Allowed VLAN list, which statement is accurate?

1. A Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.
2. Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.
3. A Layer 2 interface that can carry traffic for multiple VLANs.
4. The set of VLANs permitted to traverse a trunk link.

Correct Answer: D

 

Correct Answer

Answer D is correct because it accurately defines Allowed VLAN list. The matching definition is: The set of VLANs permitted to traverse a trunk link.

Incorrect Answers

Answer A is incorrect because the “show interfaces trunk” option describes a different concept: a Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

Answer B is incorrect because the “Subinterface encapsulation” option describes a different concept: Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

Answer C is incorrect because the “Trunk port” option describes a different concept: a Layer 2 interface that can carry traffic for multiple VLANs.

 

Question 16

For switchport mode trunk, which statement is accurate?

1. A condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.
2. A Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.
3. A field inserted into an Ethernet frame to identify its VLAN on a tagged trunk.
4. A Cisco IOS command that statically configures a Layer 2 switch port as a trunk.

Correct Answer: D

 

Correct Answer

Answer D is correct because the choice accurately describes switchport mode trunk: A Cisco IOS command that statically configures a Layer 2 switch port as a trunk.

Incorrect Answers

Answer A is incorrect because the “Native VLAN mismatch” option describes a different concept: a condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.

Answer B is incorrect because the “show interfaces trunk” option describes a different concept: a Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

Answer C is incorrect because the “802.1Q tag” option describes a different concept: a field inserted into an Ethernet frame to identify its VLAN on a tagged trunk.

 

Question 17

For show interfaces trunk, which statement is accurate?

1. A Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.
2. A condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.
3. An inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces.
4. A field inserted into an Ethernet frame to identify its VLAN on a tagged trunk.

Correct Answer: A

 

Correct Answer

Answer A is correct because the selected answer describes a Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

Incorrect Answers

Answer B is incorrect because the “Native VLAN mismatch” option describes a different concept: a condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.

Answer C is incorrect because the “Router-on-a-stick” option describes a different concept: an inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces.

Answer D is incorrect because the “802.1Q tag” option describes a different concept: a field inserted into an Ethernet frame to identify its VLAN on a tagged trunk.

 

Question 18

For Native VLAN mismatch, which statement is accurate?

1. The set of VLANs permitted to traverse a trunk link.
2. A condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.
3. The VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.
4. The Ethernet VLAN tagging standard commonly used on switch trunks.

Correct Answer: B

 

Correct Answer

Answer B is correct because the selected answer describes a condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.

Incorrect Answers

Answer A is incorrect because the “Allowed VLAN list” option describes a different concept: the set of VLANs permitted to traverse a trunk link.

Answer C is incorrect because the “Native VLAN” option describes a different concept: the VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.

Answer D is incorrect because the “802.1Q” option describes a different concept: the Ethernet VLAN tagging standard commonly used on switch trunks.

 

Question 19

For Router-on-a-stick, which statement is accurate?

1. The set of VLANs permitted to traverse a trunk link.
2. The Ethernet VLAN tagging standard commonly used on switch trunks.
3. A condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.
4. An inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces.

Correct Answer: D

 

Correct Answer

Answer D is correct because it accurately defines Router-on-a-stick. The matching definition is: An inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces.

Incorrect Answers

Answer A is incorrect because the “Allowed VLAN list” option describes a different concept: the set of VLANs permitted to traverse a trunk link.

Answer B is incorrect because the “802.1Q” option describes a different concept: the Ethernet VLAN tagging standard commonly used on switch trunks.

Answer C is incorrect because the “Native VLAN mismatch” option describes a different concept: a condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.

 

Question 20

For Subinterface encapsulation, which statement is accurate?

802. Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.
803. The VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.
804. A condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.
805. The Ethernet VLAN tagging standard commonly used on switch trunks.

Correct Answer: A

 

Correct Answer

Answer A is correct because the choice accurately describes Subinterface encapsulation: Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

Incorrect Answers

Answer B is incorrect because the “Native VLAN” option describes a different concept: the VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.

Answer C is incorrect because the “Native VLAN mismatch” option describes a different concept: a condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.

Answer D is incorrect because the “802.1Q” option describes a different concept: the Ethernet VLAN tagging standard commonly used on switch trunks.

 

Question 21

Two switches must carry several VLANs over one Ethernet link using interoperable VLAN tags. Which standard should the trunk use?

802. 802.1Q
803. Subinterface encapsulation
804. switchport mode trunk
805. show interfaces trunk

Correct Answer: A

 

Correct Answer

Answer A is correct because 802.1Q is the most precise fit for the stated requirement. The Ethernet VLAN tagging standard commonly used on switch trunks.

Incorrect Answers

Answer B is incorrect because the “Subinterface encapsulation” option describes a different concept: Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

Answer C is incorrect because the “switchport mode trunk” option describes a different concept: a Cisco IOS command that statically configures a Layer 2 switch port as a trunk.

Answer D is incorrect because the “show interfaces trunk” option describes a different concept: a Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

 

Question 22

During a network access design review, the design calls for the following capability: A Layer 2 interface that can carry traffic for multiple VLANs. Which option names that capability most accurately?

1. Router-on-a-stick
2. Native VLAN mismatch
3. switchport mode trunk
4. Trunk port

Correct Answer: D

 

Correct Answer

Answer D is correct because the scenario is describing the role of Trunk port. A Layer 2 interface that can carry traffic for multiple VLANs.

Incorrect Answers

Answer A is incorrect because the “Router-on-a-stick” option describes a different concept: an inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces.

Answer B is incorrect because the “Native VLAN mismatch” option describes a different concept: a condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.

Answer C is incorrect because the “switchport mode trunk” option describes a different concept: a Cisco IOS command that statically configures a Layer 2 switch port as a trunk.

 

Question 23

An Ethernet frame crosses a trunk with a VLAN identifier inserted into the frame. Which field carries this identifier?

802. 802.1Q tag
803. Native VLAN mismatch
804. Subinterface encapsulation
805. Allowed VLAN list

Correct Answer: A

 

Correct Answer

Answer A is correct because 802.1Q tag directly provides the function required by the scenario. A field inserted into an Ethernet frame to identify its VLAN on a tagged trunk.

Incorrect Answers

Answer B is incorrect because the “Native VLAN mismatch” option describes a different concept: a condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.

Answer C is incorrect because the “Subinterface encapsulation” option describes a different concept: Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

Answer D is incorrect because the “Allowed VLAN list” option describes a different concept: the set of VLANs permitted to traverse a trunk link.

 

Question 24

An 802.1Q trunk receives an untagged frame under its normal untagged-traffic configuration. Which VLAN assignment determines how the switch handles the frame?

1. Allowed VLAN list
2. 802.1Q
3. Native VLAN
4. Subinterface encapsulation

Correct Answer: C

 

Correct Answer

Answer C is correct because the operational requirement in the stem maps to Native VLAN: The VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.

Incorrect Answers

Answer A is incorrect because the “Allowed VLAN list” option describes a different concept: the set of VLANs permitted to traverse a trunk link.

Answer B is incorrect because the “802.1Q” option describes a different concept: the Ethernet VLAN tagging standard commonly used on switch trunks.

Answer D is incorrect because the “Subinterface encapsulation” option describes a different concept: Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

 

Question 25

In a campus access-layer change, the team must identify the technology that provides the following function: The set of VLANs permitted to traverse a trunk link. Which option should be selected?

1. Allowed VLAN list
2. 802.1Q
3. Native VLAN mismatch
4. Native VLAN

Correct Answer: A

 

Correct Answer

Answer A is correct because Allowed VLAN list is the most precise fit for the stated requirement. The set of VLANs permitted to traverse a trunk link.

Incorrect Answers

Answer B is incorrect because the “802.1Q” option describes a different concept: the Ethernet VLAN tagging standard commonly used on switch trunks.

Answer C is incorrect because the “Native VLAN mismatch” option describes a different concept: a condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.

Answer D is incorrect because the “Native VLAN” option describes a different concept: the VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.

 

Question 26

A switch-to-switch link must remain a trunk under an explicit local configuration. Which IOS interface command selects that operating mode?

1. Router-on-a-stick
2. switchport mode trunk
3. show interfaces trunk
4. 802.1Q

Correct Answer: B

 

Correct Answer

Answer B is correct because the scenario is describing the role of switchport mode trunk. A Cisco IOS command that statically configures a Layer 2 switch port as a trunk.

Incorrect Answers

Answer A is incorrect because the “Router-on-a-stick” option describes a different concept: an inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces.

Answer C is incorrect because the “show interfaces trunk” option describes a different concept: a Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

Answer D is incorrect because the “802.1Q” option describes a different concept: the Ethernet VLAN tagging standard commonly used on switch trunks.

 

Question 27

During a network access design review, the design calls for the following capability: A Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information. Which option names that capability most accurately?

1. show interfaces trunk
2. Subinterface encapsulation
3. 802.1Q
4. Native VLAN mismatch

Correct Answer: A

 

Correct Answer

Answer A is correct because show interfaces trunk directly provides the function required by the scenario. A Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

Incorrect Answers

Answer B is incorrect because the “Subinterface encapsulation” option describes a different concept: Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

Answer C is incorrect because the “802.1Q” option describes a different concept: the Ethernet VLAN tagging standard commonly used on switch trunks.

Answer D is incorrect because the “Native VLAN mismatch” option describes a different concept: a condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.

 

Question 28

The two ends of a trunk assign untagged traffic to different VLANs. Which configuration inconsistency explains the resulting connectivity and spanning-tree warnings?

1. Subinterface encapsulation
2. show interfaces trunk
3. Native VLAN mismatch
4. Trunk port

Correct Answer: C

 

Correct Answer

Answer C is correct because the operational requirement in the stem maps to Native VLAN mismatch: A condition where the two ends of a trunk use different native VLANs, potentially causing traffic and spanning-tree problems.

Incorrect Answers

Answer A is incorrect because the “Subinterface encapsulation” option describes a different concept: Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

Answer B is incorrect because the “show interfaces trunk” option describes a different concept: a Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

Answer D is incorrect because the “Trunk port” option describes a different concept: a Layer 2 interface that can carry traffic for multiple VLANs.

 

Question 29

While working on a Layer 2 troubleshooting session, an administrator encounters this requirement: An inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces. Which answer is the most precise match?

1. Native VLAN
2. Router-on-a-stick
3. Subinterface encapsulation
4. show interfaces trunk

Correct Answer: B

 

Correct Answer

Answer B is correct because Router-on-a-stick is the most precise fit for the stated requirement. An inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces.

Incorrect Answers

Answer A is incorrect because the “Native VLAN” option describes a different concept: the VLAN whose frames are normally sent untagged over an 802.1Q trunk unless native VLAN tagging is enabled.

Answer C is incorrect because the “Subinterface encapsulation” option describes a different concept: Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

Answer D is incorrect because the “show interfaces trunk” option describes a different concept: a Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

 

Question 30

In a campus access-layer change, the team must identify the technology that provides the following function: Router configuration that associates a logical subinterface with an 802.1Q VLAN ID. Which option should be selected?

1. show interfaces trunk
2. 802.1Q tag
3. Subinterface encapsulation
4. Router-on-a-stick

Correct Answer: C

 

Correct Answer

Answer C is correct because the scenario is describing the role of Subinterface encapsulation. Router configuration that associates a logical subinterface with an 802.1Q VLAN ID.

Incorrect Answers

Answer A is incorrect because the “show interfaces trunk” option describes a different concept: a Cisco IOS command used to verify trunk state, native VLAN, and allowed/forwarding VLAN information.

Answer B is incorrect because the “802.1Q tag” option describes a different concept: a field inserted into an Ethernet frame to identify its VLAN on a tagged trunk.

Answer D is incorrect because the “Router-on-a-stick” option describes a different concept: an inter-VLAN routing design that uses one physical router interface with multiple 802.1Q subinterfaces.