Topic 06 Practice Test 2 covers VLANs, Trunks, and Inter-VLAN Connectivity for Cisco Certified Network Associate 200-301 CCNA and maps to objectives 2.1–2.2. For broader exam preparation, review the Cisco CCNA 200-301 Exam Dumps. Every option includes focused technical reasoning explaining both the networking concept and its fit to the scenario.
Question 1
Beacon users on Gi1/0/12 are landing in VLAN 1 even though the port should serve only accounting VLAN 30. Which change directly corrects the access-port assignment? Choose ONE.
- no switchport
ip address 10.30.0.1 255.255.255.0 - switchport mode access
switchport access vlan 30 - switchport mode trunk
switchport trunk native vlan 30 - switchport voice vlan 30
Correct Answer: B
Correct Answer
Answer B is correct because `switchport mode access` prevents trunk negotiation and `switchport access vlan 30` places untagged frames from the attached endpoint into VLAN 30. At Beacon, access VLAN troubleshooting uses this evidence. The switchport mode path at Beacon therefore meets the stated constraint. At Beacon, the access VLAN state is observable afterward.
Incorrect Answers
Answer C is incorrect because A trunk can carry multiple VLANs; setting VLAN 30 native does not make the interface a single-VLAN access port for the PC. At Beacon, access VLAN troubleshooting uses this evidence. The switchport mode path at Beacon therefore misses the stated constraint. At Beacon, the access VLAN state is observable afterward.
Answer D is incorrect because `switchport voice vlan 30` identifies a voice VLAN for an attached IP phone while the access VLAN remains separately configured for ordinary endpoint traffic. At Beacon, access VLAN troubleshooting uses this evidence. The switchport voice path at Beacon therefore misses the stated constraint. At Beacon, the access VLAN state is observable afterward.
Answer A is incorrect because `no switchport` converts a capable switch port to a routed Layer 3 interface, so it no longer performs the requested Layer 2 access-VLAN function. At Beacon, access VLAN troubleshooting uses this evidence. The no switchport path at Beacon therefore misses the stated constraint. At Beacon, the access VLAN state is observable afterward.
Question 2
At Ember, phones register in VLAN 20 with PCs instead of using the dedicated voice VLAN 120. The switchport already has `switchport access vlan 20`. Which additional command fixes the voice classification? Choose ONE.
- switchport mode access
switchport access vlan 20
switchport voice vlan 120 - switchport mode trunk
switchport trunk allowed vlan 20,120 - no switchport
ip address 10.20.0.1 255.255.255.0 - switchport access vlan 120
switchport voice vlan 20
Correct Answer: A
Correct Answer
Answer A is correct because An access port can support a data VLAN plus a separate voice VLAN; the phone tags voice frames for VLAN 120 while ordinary PC traffic belongs to access VLAN 20. At Ember, data voice VLAN troubleshooting uses this evidence. The switchport mode path at Ember therefore meets the stated constraint. At Ember, the data voice VLAN state is observable afterward.
Incorrect Answers
Answer B is incorrect because A static trunk would expose trunk behavior to the endpoint connection and is not the normal access-plus-voice configuration expected for a Cisco IP phone and attached PC. At Ember, data voice VLAN troubleshooting uses this evidence. The switchport mode path at Ember therefore misses the stated constraint. At Ember, the data voice VLAN state is observable afterward.
Answer D is incorrect because Reversing the access and voice VLANs places untagged PC data in VLAN 120 and advertises VLAN 20 to the phone, the opposite of the stated design. At Ember, data voice VLAN troubleshooting uses this evidence. The switchport access path at Ember therefore misses the stated constraint. At Ember, the data voice VLAN state is observable afterward.
Answer C is incorrect because A routed port removes Layer 2 VLAN membership and therefore cannot provide the simultaneous access and voice VLAN behavior required here. At Ember, data voice VLAN troubleshooting uses this evidence. The no switchport path at Ember therefore misses the stated constraint. At Ember, the data voice VLAN state is observable afterward.
Question 3
Harbor’s switch-to-switch link carries only the access VLAN even though the allowed list is correct. `show interfaces trunk` does not list Gi1/0/47. Which missing command most directly explains the problem? Choose ONE.
- switchport mode access
- switchport mode trunk
- switchport access vlan 10
- no switchport
Correct Answer: B
Correct Answer
Answer B is correct because `switchport mode trunk` statically places the Layer 2 interface in trunk mode so it can carry multiple VLANs with 802.1Q tagging. At Harbor, static trunk troubleshooting uses this evidence. The switchport mode path at Harbor therefore meets the stated constraint. At Harbor, the static trunk state is observable afterward.
Incorrect Answers
Answer A is incorrect because Access mode carries one access VLAN for ordinary Layer 2 endpoint traffic and does not create the requested multi-VLAN interswitch trunk. At Harbor, static trunk troubleshooting uses this evidence. The switchport mode path at Harbor therefore misses the stated constraint. At Harbor, the static trunk state is observable afterward.
Answer C is incorrect because `switchport access vlan 10` selects an access VLAN only when the interface operates as an access port; it does not establish trunking. At Harbor, static trunk troubleshooting uses this evidence. The switchport access path at Harbor therefore misses the stated constraint. At Harbor, the static trunk state is observable afterward.
Answer D is incorrect because `no switchport` changes a supported interface into a routed Layer 3 port, removing the Layer 2 trunk function entirely. At Harbor, static trunk troubleshooting uses this evidence. The no switchport path at Harbor therefore misses the stated constraint. At Harbor, the static trunk state is observable afterward.
Question 4
Keystone lost VLAN 10 and 20 connectivity after an engineer typed `switchport trunk allowed vlan 30`. Which corrected command would add VLAN 30 while preserving the current allowed list? Choose ONE.
- switchport trunk allowed vlan add 30
- switchport access vlan 30
- switchport trunk allowed vlan 30
- switchport trunk native vlan 30
Correct Answer: A
Correct Answer
Answer A is correct because The `add` keyword appends VLAN 30 to the existing trunk allowed list instead of replacing the list, preserving VLANs that are already permitted. At Keystone, allowed VLAN troubleshooting uses this evidence. The switchport trunk path at Keystone therefore meets the stated constraint. At Keystone, the allowed VLAN state is observable afterward.
Incorrect Answers
Answer C is incorrect because Without `add`, the command defines the allowed list as VLAN 30, which can remove previously permitted VLANs and interrupt their traffic. At Keystone, allowed VLAN troubleshooting uses this evidence. The switchport trunk path at Keystone therefore misses the stated constraint. At Keystone, the allowed VLAN state is observable afterward.
Answer B is incorrect because `switchport access vlan 30` applies to access-port VLAN membership; it does not update the VLAN allow list of a trunk. At Keystone, allowed VLAN troubleshooting uses this evidence. The switchport access path at Keystone therefore misses the stated constraint. At Keystone, the allowed VLAN state is observable afterward.
Answer D is incorrect because `switchport trunk native vlan 30` changes the native VLAN used for untagged trunk traffic but does not add VLAN 30 to the allowed list as requested. At Keystone, allowed VLAN troubleshooting uses this evidence. The switchport trunk path at Keystone therefore misses the stated constraint. At Keystone, the allowed VLAN state is observable afterward.
Question 5
Northstar sees a native-VLAN mismatch warning: one end uses VLAN 1 and the other uses VLAN 99. Which change on the VLAN 1 side aligns the trunk? Choose ONE.
- switchport access vlan 99
- switchport voice vlan 99
- switchport trunk allowed vlan 99
- switchport trunk native vlan 99
Correct Answer: D
Correct Answer
Answer D is correct because `switchport trunk native vlan 99` makes VLAN 99 the native VLAN on the 802.1Q trunk; native VLAN settings should match at both ends of the link. At Northstar, native VLAN troubleshooting uses this evidence. The switchport trunk path at Northstar therefore meets the stated constraint. At Northstar, the native VLAN state is observable afterward.
Incorrect Answers
Answer C is incorrect because Allowing VLAN 99 controls whether tagged VLAN 99 traffic can traverse the trunk but does not select which VLAN receives untagged trunk frames. At Northstar, native VLAN troubleshooting uses this evidence. The switchport trunk path at Northstar therefore misses the stated constraint. At Northstar, the native VLAN state is observable afterward.
Answer A is incorrect because An access-VLAN command applies to an access port and does not define native-VLAN handling on a trunk. At Northstar, native VLAN troubleshooting uses this evidence. The switchport access path at Northstar therefore misses the stated constraint. At Northstar, the native VLAN state is observable afterward.
Answer B is incorrect because A voice-VLAN command is intended for endpoint access ports with IP phones and does not establish an 802.1Q trunk native VLAN. At Northstar, native VLAN troubleshooting uses this evidence. The switchport voice path at Northstar therefore misses the stated constraint. At Northstar, the native VLAN state is observable afterward.
Question 6
Quartz’s router-on-a-stick subinterface Gi0/0.20 has an IP address but never receives VLAN 20 frames. The switch trunk is correct. Which missing router command is the most likely cause? Choose ONE.
- encapsulation dot1Q 20
- switchport access vlan 20
- ip helper-address 20.20.20.20
- encapsulation ppp
Correct Answer: A
Correct Answer
Answer A is correct because `encapsulation dot1Q 20` associates the router subinterface with 802.1Q VLAN 20 so tagged frames are accepted and routed through that logical interface. At Quartz, router subinterface troubleshooting uses this evidence. The encapsulation dot1Q path at Quartz therefore meets the stated constraint. At Quartz, the router subinterface state is observable afterward.
Incorrect Answers
Answer B is incorrect because `switchport access vlan 20` is a Layer 2 switchport command and is not the router subinterface command that identifies an 802.1Q VLAN. At Quartz, router subinterface troubleshooting uses this evidence. The switchport access path at Quartz therefore misses the stated constraint. At Quartz, the router subinterface state is observable afterward.
Answer C is incorrect because `ip helper-address` relays selected UDP broadcasts such as DHCP; it does not identify which VLAN an Ethernet subinterface terminates. At Quartz, router subinterface troubleshooting uses this evidence. The ip helper-address path at Quartz therefore misses the stated constraint. At Quartz, the router subinterface state is observable afterward.
Answer D is incorrect because PPP encapsulation is used on point-to-point WAN-style links and does not map an Ethernet router subinterface to an 802.1Q VLAN. At Quartz, router subinterface troubleshooting uses this evidence. The encapsulation ppp path at Quartz therefore misses the stated constraint. At Quartz, the router subinterface state is observable afterward.
Question 7
Tundra can ping each SVI locally, but hosts in VLAN 10 cannot reach VLAN 20. Layer 2 VLAN membership is correct and both SVIs are up. Which missing setting is most likely? Choose ONE.
- ip default-gateway 10.10.10.1
- ip routing
- spanning-tree portfast
- switchport mode trunk
Correct Answer: B
Correct Answer
Answer B is correct because `ip routing` enables IPv4 packet forwarding on a multilayer switch so traffic can be routed between directly connected SVIs. At Tundra, SVI routing troubleshooting uses this evidence. The ip routing path at Tundra therefore meets the stated constraint. At Tundra, the SVI routing state is observable afterward.
Incorrect Answers
Answer C is incorrect because PortFast changes spanning-tree convergence behavior on edge ports and does not enable Layer 3 forwarding between VLAN interfaces. At Tundra, SVI routing troubleshooting uses this evidence. The spanning-tree portfast path at Tundra therefore misses the stated constraint. At Tundra, the SVI routing state is observable afterward.
Answer D is incorrect because Trunk mode is configured on a Layer 2 interface to carry VLANs; it does not globally enable routing between SVIs. At Tundra, SVI routing troubleshooting uses this evidence. The switchport mode path at Tundra therefore misses the stated constraint. At Tundra, the SVI routing state is observable afterward.
Answer A is incorrect because `ip default-gateway` is used for management reachability when a switch is not routing; it is not a substitute for enabling Layer 3 forwarding on a multilayer switch. At Tundra, SVI routing troubleshooting uses this evidence. The ip default-gateway path at Tundra therefore misses the stated constraint. At Tundra, the SVI routing state is observable afterward.
Question 8
Cobalt users on Gi1/0/18 cannot communicate in VLAN 40. Before changing the trunk, the engineer wants to confirm whether Gi1/0/18 is assigned to VLAN 40 in the VLAN database view. Which command should be used? Choose ONE.
- show cdp neighbors
- show vlan brief
- show etherchannel summary
- show ip route
Correct Answer: B
Correct Answer
Answer B is correct because `show vlan brief` summarizes VLAN IDs, names, status, and access-port membership, making it the direct verification command for the requested Layer 2 state. At Cobalt, VLAN database troubleshooting uses this evidence. The show vlan path at Cobalt therefore meets the stated constraint. At Cobalt, the VLAN database state is observable afterward.
Incorrect Answers
Answer D is incorrect because `show ip route` displays Layer 3 routing information; it does not list access-port membership in VLANs. At Cobalt, VLAN database troubleshooting uses this evidence. The show ip path at Cobalt therefore misses the stated constraint. At Cobalt, the VLAN database state is observable afterward.
Answer C is incorrect because `show etherchannel summary` verifies port-channel membership and state rather than VLAN database membership for individual access ports. At Cobalt, VLAN database troubleshooting uses this evidence. The show etherchannel path at Cobalt therefore misses the stated constraint. At Cobalt, the VLAN database state is observable afterward.
Answer A is incorrect because `show cdp neighbors` discovers directly connected Cisco devices and provides neighbor details, not the switch’s VLAN membership table. At Cobalt, VLAN database troubleshooting uses this evidence. The show cdp path at Cobalt therefore misses the stated constraint. At Cobalt, the VLAN database state is observable afterward.
Question 9
Falcon’s security baseline requires a statically configured trunk to a third-party firewall and prohibits Dynamic Trunking Protocol negotiation. Which interface command meets the requirement? Choose ONE.
- switchport access vlan 1
- switchport mode dynamic auto
- switchport mode dynamic desirable
- switchport nonegotiate
Correct Answer: D
Correct Answer
Answer D is correct because `switchport nonegotiate` suppresses DTP negotiation frames; paired with static trunk configuration it is appropriate when the peer does not participate in DTP. At Falcon, DTP suppression troubleshooting uses this evidence. The switchport nonegotiate path at Falcon therefore meets the stated constraint. At Falcon, the DTP suppression state is observable afterward.
Incorrect Answers
Answer C is incorrect because Dynamic desirable actively tries to negotiate trunking with DTP, directly conflicting with the requirement to suppress negotiation. At Falcon, DTP suppression troubleshooting uses this evidence. The switchport mode path at Falcon therefore misses the stated constraint. At Falcon, the DTP suppression state is observable afterward.
Answer B is incorrect because Dynamic auto still relies on DTP negotiation to become a trunk and therefore is not the deterministic no-DTP configuration requested. At Falcon, DTP suppression troubleshooting uses this evidence. The switchport mode path at Falcon therefore misses the stated constraint. At Falcon, the DTP suppression state is observable afterward.
Answer A is incorrect because Assigning an access VLAN changes access-port membership and does not disable DTP on an interface intended to remain a trunk. At Falcon, DTP suppression troubleshooting uses this evidence. The switchport access path at Falcon therefore misses the stated constraint. At Falcon, the DTP suppression state is observable afterward.
Question 10
Ion’s `show interfaces trunk` shows VLAN 50 in the configured allowed list but not among VLANs allowed and active in the management domain. Which condition should be checked first? Choose ONE.
- Create VLAN 50 in the local VLAN database
- Configure an IP address on every access port
- Make VLAN 50 the native VLAN
- Enable PortFast on the trunk
Correct Answer: A
Correct Answer
Answer A is correct because A trunk allowed list only permits a VLAN to cross the link; the VLAN must also exist and be active locally for normal Layer 2 switching in that VLAN. At Ion, allowed active VLAN troubleshooting uses this evidence. The Create VLAN path at Ion therefore meets the stated constraint. At Ion, the allowed active VLAN state is observable afterward.
Incorrect Answers
Answer C is incorrect because Making VLAN 50 native changes how untagged frames are classified; it does not create the VLAN in the local VLAN database. At Ion, allowed active VLAN troubleshooting uses this evidence. The Make VLAN path at Ion therefore misses the stated constraint. At Ion, the allowed active VLAN state is observable afterward.
Answer D is incorrect because PortFast affects spanning-tree transition behavior and is not what makes an allowed VLAN exist or become active on the switch. At Ion, allowed active VLAN troubleshooting uses this evidence. The Enable PortFast path at Ion therefore misses the stated constraint. At Ion, the allowed active VLAN state is observable afterward.
Answer B is incorrect because Layer 2 access ports do not require per-port IP addresses to switch VLAN traffic, so this does not address the missing VLAN state. At Ion, allowed active VLAN troubleshooting uses this evidence. The Configure an path at Ion therefore misses the stated constraint. At Ion, the allowed active VLAN state is observable afterward.
Question 11
Lumen’s uplink should have IP address 10.0.0.1/30, but the switch rejects the address because the interface remains a Layer 2 switchport. Which command should be entered first? Choose ONE.
- switchport mode trunk
- switchport trunk native vlan 1
- switchport mode access
- no switchport
Correct Answer: D
Correct Answer
Answer D is correct because `no switchport` converts a supported multilayer-switch interface to a routed Layer 3 port, allowing an IP address to be configured directly on it. At Lumen, routed port troubleshooting uses this evidence. The no switchport path at Lumen therefore meets the stated constraint. At Lumen, the routed port state is observable afterward.
Incorrect Answers
Answer A is incorrect because Trunk mode keeps the interface operating at Layer 2 and carries VLANs rather than turning the physical link into a routed port. At Lumen, routed port troubleshooting uses this evidence. The switchport mode path at Lumen therefore misses the stated constraint. At Lumen, the routed port state is observable afterward.
Answer C is incorrect because Access mode is also Layer 2 operation and assigns untagged traffic to one VLAN instead of enabling a Layer 3 interface address. At Lumen, routed port troubleshooting uses this evidence. The switchport mode path at Lumen therefore misses the stated constraint. At Lumen, the routed port state is observable afterward.
Answer B is incorrect because Changing the native VLAN applies only to a Layer 2 trunk and does not convert the interface to routed operation. At Lumen, routed port troubleshooting uses this evidence. The switchport trunk path at Lumen therefore misses the stated constraint. At Lumen, the routed port state is observable afterward.
Question 12
Orchid sees VLAN 20 configured locally but missing from the trunk’s permitted set. Which TWO checks together determine whether VLAN 20 can be carried normally on that trunk? Choose TWO.
- VLAN 20 is included in the trunk allowed list
- VLAN 20 exists and is active locally
- Every VLAN 20 host has the same default gateway MAC
- VLAN 20 is configured as the native VLAN
- PortFast is enabled on the trunk
Correct Answers: A, B
Correct Answers
Answer B is correct because The VLAN must exist and be active in the switch’s VLAN database; otherwise an allow-list entry alone does not create a usable local Layer 2 domain. At Orchid, trunk eligibility troubleshooting uses this evidence. The VLAN 20 path at Orchid therefore meets the stated constraint. At Orchid, the trunk eligibility state is observable afterward.
Answer A is correct because The trunk’s allowed list must permit VLAN 20; a locally active VLAN that is filtered from the trunk will not be carried across that link. At Orchid, trunk eligibility troubleshooting uses this evidence. The VLAN 20 path at Orchid therefore meets the stated constraint. At Orchid, the trunk eligibility state is observable afterward.
Incorrect Answers
Answer D is incorrect because Native-VLAN status is not required for a VLAN to traverse a trunk; non-native VLANs normally cross with 802.1Q tags. At Orchid, trunk eligibility troubleshooting uses this evidence. The VLAN 20 path at Orchid therefore misses the stated constraint. At Orchid, the trunk eligibility state is observable afterward.
Answer C is incorrect because Host gateway MAC addresses are learned dynamically and are unrelated to whether a VLAN is allowed and active on the trunk itself. At Orchid, trunk eligibility troubleshooting uses this evidence. The Every VLAN path at Orchid therefore misses the stated constraint. At Orchid, the trunk eligibility state is observable afterward.
Answer E is incorrect because PortFast controls spanning-tree convergence and is not a prerequisite for a VLAN to exist locally or be admitted by the trunk filter. At Orchid, trunk eligibility troubleshooting uses this evidence. The PortFast is path at Orchid therefore misses the stated constraint. At Orchid, the trunk eligibility state is observable afterward.
Question 13
Redwood’s switch sends VLAN 99 traffic untagged on the trunk, but the router subinterface expects tagged VLAN 99 frames. Which router-side change aligns native-VLAN treatment? Choose ONE.
- switchport trunk native vlan 99
- encapsulation dot1Q 99
- encapsulation dot1Q 99 native
- ip address dhcp
Correct Answer: C
Correct Answer
Answer C is correct because Adding the `native` keyword to `encapsulation dot1Q 99 native` tells the router subinterface to treat VLAN 99 as the untagged native VLAN on that 802.1Q link. At Redwood, native subinterface troubleshooting uses this evidence. The encapsulation dot1Q path at Redwood therefore meets the stated constraint. At Redwood, the native subinterface state is observable afterward.
Incorrect Answers
Answer B is incorrect because `encapsulation dot1Q 99` maps tagged VLAN 99 frames but does not declare VLAN 99 native, so it conflicts with the switch sending that VLAN untagged. At Redwood, native subinterface troubleshooting uses this evidence. The encapsulation dot1Q path at Redwood therefore misses the stated constraint. At Redwood, the native subinterface state is observable afterward.
Answer A is incorrect because `switchport trunk native vlan 99` is a switchport command; it is not the syntax used under a router Ethernet subinterface. At Redwood, native subinterface troubleshooting uses this evidence. The switchport trunk path at Redwood therefore misses the stated constraint. At Redwood, the native subinterface state is observable afterward.
Answer D is incorrect because `ip address dhcp` controls how an interface obtains an IP address and does not define 802.1Q VLAN encapsulation or native-VLAN behavior. At Redwood, native subinterface troubleshooting uses this evidence. The ip address path at Redwood therefore misses the stated constraint. At Redwood, the native subinterface state is observable afterward.
Question 14
Beacon receives reports that VLAN 30 stopped crossing the uplink. The engineer wants one trunk-focused command that shows port status, native VLAN, and allowed VLAN sets. Which command should be checked first? Choose ONE.
- show ip interface brief
- show spanning-tree root
- show interfaces trunk
- show vlan brief
Correct Answer: C
Correct Answer
Answer C is correct because `show interfaces trunk` is the trunk-focused summary that shows trunking ports, native VLANs, and the configured/active/forwarding VLAN sets relevant to the fault. At Beacon, trunk verification troubleshooting uses this evidence. The show interfaces path at Beacon therefore meets the stated constraint. At Beacon, the trunk verification state is observable afterward.
Incorrect Answers
Answer D is incorrect because `show vlan brief` is useful for VLAN database and access-port membership but does not provide the same trunk-specific allowed/native/forwarding view. At Beacon, trunk verification troubleshooting uses this evidence. The show vlan path at Beacon therefore misses the stated constraint. At Beacon, the trunk verification state is observable afterward.
Answer A is incorrect because `show ip interface brief` summarizes Layer 3 interface addresses and line/protocol status, not 802.1Q trunk VLAN filtering. At Beacon, trunk verification troubleshooting uses this evidence. The show ip path at Beacon therefore misses the stated constraint. At Beacon, the trunk verification state is observable afterward.
Answer B is incorrect because `show spanning-tree root` focuses on root-bridge information and does not summarize trunk encapsulation, native VLAN, and allowed VLAN lists. At Beacon, trunk verification troubleshooting uses this evidence. The show spanning-tree path at Beacon therefore misses the stated constraint. At Beacon, the trunk verification state is observable afterward.
Question 15
Ember suspects Gi1/0/22 was accidentally changed from access to dynamic operation. Which command exposes both administrative and operational switchport modes? Choose ONE.
- show interfaces Gi1/0/22 switchport
- show interfaces Gi1/0/22 counters errors
- show mac address-table dynamic
- show ip route connected
Correct Answer: A
Correct Answer
Answer A is correct because `show interfaces … switchport` displays administrative and operational switchport mode plus VLAN-related properties, which directly answers the requested Layer 2 verification questions. At Ember, switchport detail troubleshooting uses this evidence. The show interfaces path at Ember therefore meets the stated constraint. At Ember, the switchport detail state is observable afterward.
Incorrect Answers
Answer B is incorrect because Interface error counters are valuable for physical or frame-error troubleshooting but do not identify the switchport’s access/trunk/VLAN configuration. At Ember, switchport detail troubleshooting uses this evidence. The show interfaces path at Ember therefore misses the stated constraint. At Ember, the switchport detail state is observable afterward.
Answer C is incorrect because The MAC address table shows learned source MAC locations and VLANs, not the administrative and operational mode settings of one switchport. At Ember, switchport detail troubleshooting uses this evidence. The show mac path at Ember therefore misses the stated constraint. At Ember, the switchport detail state is observable afterward.
Answer D is incorrect because The connected route table shows Layer 3 networks associated with routed interfaces and SVIs, not detailed Layer 2 switchport state. At Ember, switchport detail troubleshooting uses this evidence. The show ip path at Ember therefore misses the stated constraint. At Ember, the switchport detail state is observable afterward.
Question 16
Keystone captures traffic on a phone-plus-PC access port and sees voice frames tagged for VLAN 120 while ordinary PC frames arrive untagged. Is this behavior consistent with the intended configuration? Choose ONE.
- Voice VLAN configuration turns the switchport into a Layer 3 routed interface
- Both PC and phone traffic must be sent untagged in the voice VLAN
- The PC’s ordinary traffic uses the access VLAN while the phone can tag voice traffic for the configured voice VLAN
- The port becomes an 802.1Q trunk with unrestricted VLAN access to the PC
Correct Answer: C
Correct Answer
Answer C is correct because Cisco access-plus-voice operation keeps ordinary endpoint data associated with the access VLAN while the IP phone can identify/tag voice traffic for the separate configured voice VLAN. At Keystone, phone data voice troubleshooting uses this evidence. The The PC’s path at Keystone therefore meets the stated constraint. At Keystone, the phone data voice state is observable afterward.
Incorrect Answers
Answer B is incorrect because Putting both traffic classes untagged into the voice VLAN defeats the separate data/voice VLAN design and is not the behavior created by access plus voice VLAN configuration. At Keystone, phone data voice troubleshooting uses this evidence. The Both PC path at Keystone therefore misses the stated constraint. At Keystone, the phone data voice state is observable afterward.
Answer D is incorrect because The presence of a voice VLAN does not make the endpoint port an unrestricted infrastructure trunk; the PC does not gain arbitrary VLAN carriage. At Keystone, phone data voice troubleshooting uses this evidence. The The port path at Keystone therefore misses the stated constraint. At Keystone, the phone data voice state is observable afterward.
Answer A is incorrect because Voice VLAN configuration remains a Layer 2 switchport feature and does not convert the interface into a routed Layer 3 port. At Keystone, phone data voice troubleshooting uses this evidence. The Voice VLAN path at Keystone therefore misses the stated constraint. At Keystone, the phone data voice state is observable afterward.
Question 17
Northstar’s VLAN 10 host has address 10.10.10.25/24 but gateway 10.20.20.1, which is the SVI for VLAN 20. Local VLAN traffic works but routed traffic fails. What should the gateway be changed to? Choose ONE.
- The physical switchport’s MAC address
- 10.10.10.255
- 10.20.20.1
- 10.10.10.1
Correct Answer: D
Correct Answer
Answer D is correct because The host’s default gateway should be an IP address on the local subnet that routes off-subnet traffic; the VLAN 10 SVI at 10.10.10.1 provides that Layer 3 function. At Northstar, default gateway troubleshooting uses this evidence. The 10.10.10.1 path at Northstar therefore meets the stated constraint. At Northstar, the default gateway state is observable afterward.
Incorrect Answers
Answer C is incorrect because 10.20.20.1 belongs to a different IP subnet, so a normal VLAN 10 host cannot use it as its directly reachable default gateway. At Northstar, default gateway troubleshooting uses this evidence. The 10.20.20.1 path at Northstar therefore misses the stated constraint. At Northstar, the default gateway state is observable afterward.
Answer B is incorrect because 10.10.10.255 is the directed broadcast address for the /24 and cannot be assigned as the host’s gateway interface address. At Northstar, default gateway troubleshooting uses this evidence. The 10.10.10.255 path at Northstar therefore misses the stated constraint. At Northstar, the default gateway state is observable afterward.
Answer A is incorrect because A default gateway is configured as an IP next hop, not as a switchport MAC address; ARP resolves the selected gateway IP to a MAC when needed. At Northstar, default gateway troubleshooting uses this evidence. The The physical path at Northstar therefore misses the stated constraint. At Northstar, the default gateway state is observable afterward.
Question 18
Quartz’s analyzer sees VLAN 20 frames without an 802.1Q VLAN identifier even though VLAN 99 is the configured native VLAN. Which expectation should guide troubleshooting? Choose ONE.
- Only the access VLAN command determines tagging on a trunk
- All VLANs are identified only by source MAC address, not tags
- Native VLAN 99 traffic is normally untagged; VLAN 20 traffic is normally tagged
- VLAN 20 and VLAN 99 are both always untagged
Correct Answer: C
Correct Answer
Answer C is correct because On a conventional 802.1Q trunk, non-native VLAN traffic carries an 802.1Q tag while native-VLAN traffic is normally transmitted untagged, allowing the receiver to classify untagged frames into the native VLAN. At Quartz, 802.1Q tagging troubleshooting uses this evidence. The Native VLAN path at Quartz therefore meets the stated constraint. At Quartz, the 802.1Q tagging state is observable afterward.
Incorrect Answers
Answer D is incorrect because If multiple VLANs were all sent untagged on the same trunk there would be no VLAN identifier to distinguish them, so that does not describe normal 802.1Q trunk behavior. At Quartz, 802.1Q tagging troubleshooting uses this evidence. The VLAN 20 path at Quartz therefore misses the stated constraint. At Quartz, the 802.1Q tagging state is observable afterward.
Answer B is incorrect because MAC addresses identify endpoints, not the VLAN membership of frames traversing an 802.1Q trunk; the VLAN tag provides that segmentation for non-native VLANs. At Quartz, 802.1Q tagging troubleshooting uses this evidence. The All VLANs path at Quartz therefore misses the stated constraint. At Quartz, the 802.1Q tagging state is observable afterward.
Answer A is incorrect because Access-VLAN configuration applies to access-mode ports; trunk tagging behavior is governed by trunk/native-VLAN settings and 802.1Q operation. At Quartz, 802.1Q tagging troubleshooting uses this evidence. The Only the path at Quartz therefore misses the stated constraint. At Quartz, the 802.1Q tagging state is observable afterward.
Question 19
Tundra discovers that a trunk currently permits all VLANs even though policy allows only 10,20,30. Which configuration narrows VLAN carriage to the approved set? Choose ONE.
- switchport access vlan 10
- switchport trunk native vlan 10
- spanning-tree vlan 10 priority 4096
- switchport trunk allowed vlan 10,20,30
Correct Answer: D
Correct Answer
Answer D is correct because The trunk allowed-VLAN list is the filtering control that limits which VLANs can be carried over the trunk, so specifying 10,20,30 enforces the stated scope. At Tundra, trunk filtering troubleshooting uses this evidence. The switchport trunk path at Tundra therefore meets the stated constraint. At Tundra, the trunk filtering state is observable afterward.
Incorrect Answers
Answer B is incorrect because The native-VLAN command determines treatment of untagged frames; it does not restrict the trunk to only the listed user VLANs. At Tundra, trunk filtering troubleshooting uses this evidence. The switchport trunk path at Tundra therefore misses the stated constraint. At Tundra, the trunk filtering state is observable afterward.
Answer A is incorrect because An access-VLAN command applies to an access port and does not define the set of VLANs carried by a trunk. At Tundra, trunk filtering troubleshooting uses this evidence. The switchport access path at Tundra therefore misses the stated constraint. At Tundra, the trunk filtering state is observable afterward.
Answer C is incorrect because Spanning-tree priority affects root-bridge election for a VLAN but does not configure trunk VLAN admission. At Tundra, trunk filtering troubleshooting uses this evidence. The spanning-tree vlan path at Tundra therefore misses the stated constraint. At Tundra, the trunk filtering state is observable afterward.
Question 20
Cobalt’s router-on-a-stick path is down for both VLANs. Which TWO foundational configuration areas should be verified before investigating host applications? Choose TWO.
- Each router subinterface has matching `encapsulation dot1Q <vlan-id>`
- The switch link to the router operates as an 802.1Q trunk carrying the VLANs
- The router physical interface must be configured as a switchport
- Each VLAN must use the same IP subnet
- The switch link uses PortFast trunk mode
Correct Answers: A, B
Correct Answers
Answer B is correct because The switch-to-router link must carry the relevant VLANs as an 802.1Q trunk so frames from multiple Layer 2 domains reach the single physical router interface. At Cobalt, router-on-a-stick troubleshooting uses this evidence. The The switch path at Cobalt therefore meets the stated constraint. At Cobalt, the router-on-a-stick state is observable afterward.
Answer A is correct because Each router subinterface needs the matching 802.1Q VLAN identifier so the router can terminate the correct tagged frames and route between the associated IP networks. At Cobalt, router-on-a-stick troubleshooting uses this evidence. The Each router path at Cobalt therefore meets the stated constraint. At Cobalt, the router-on-a-stick state is observable afterward.
Incorrect Answers
Answer E is incorrect because PortFast may be considered in specific edge designs but it is not a fundamental requirement that binds VLAN tags to router subinterfaces for router-on-a-stick. At Cobalt, router-on-a-stick troubleshooting uses this evidence. The The switch path at Cobalt therefore misses the stated constraint. At Cobalt, the router-on-a-stick state is observable afterward.
Answer D is incorrect because Different VLANs normally correspond to different IP subnets for inter-VLAN routing; putting both VLANs in the same subnet would undermine the routed boundary. At Cobalt, router-on-a-stick troubleshooting uses this evidence. The Each VLAN path at Cobalt therefore misses the stated constraint. At Cobalt, the router-on-a-stick state is observable afterward.
Answer C is incorrect because A router Ethernet interface used for subinterfaces is not configured as a Layer 2 switchport; 802.1Q encapsulation is defined on the router subinterfaces. At Cobalt, router-on-a-stick troubleshooting uses this evidence. The The router path at Cobalt therefore misses the stated constraint. At Cobalt, the router-on-a-stick state is observable afterward.
