Question 1hardmultiple choice
Full question →hardmultiple choiceObjective-mapped
A multilayer switch has SVIs for VLAN 10 and VLAN 20, but hosts in those VLANs still cannot reach each other. The SVIs are up/up. Which additional condition is most likely required?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
A
Best answer
IP routing must be enabled on the multilayer switch
This is correct because the switch needs Layer 3 routing enabled to route between active SVIs.
B
Distractor review
Every access port must be converted to a trunk
This is wrong because host-facing access ports do not all need to become trunks for inter-VLAN routing.
C
Distractor review
DHCP snooping must be disabled globally
This is wrong because DHCP snooping does not generally determine whether SVIs can route between VLANs.
D
Distractor review
The switch must remove all VLAN assignments
This is wrong because VLAN assignments are central to the design, not something to remove.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is assuming that simply configuring SVIs and seeing them up/up means inter-VLAN routing is automatically enabled. Candidates often forget that the multilayer switch requires the global "ip routing" command to activate its Layer 3 routing capabilities. Without this command, the switch treats SVIs as isolated interfaces and does not forward traffic between VLANs. This misunderstanding leads to confusion when hosts in different VLANs cannot communicate despite correct VLAN and SVI configurations.
Technical deep dive
How to think about this question
A multilayer switch (MLS) combines Layer 2 switching and Layer 3 routing capabilities in a single device. It uses Switched Virtual Interfaces (SVIs) as logical Layer 3 interfaces for VLANs, allowing the switch to route traffic between VLANs internally without needing an external router. Each SVI represents the default gateway for hosts in its VLAN, enabling inter-VLAN communication when routing is active. However, having SVIs up/up only means the VLAN interfaces are operational at Layer 3. For inter-VLAN routing to function, the multilayer switch must have IP routing explicitly enabled. Without enabling IP routing, the device treats SVIs as separate interfaces but does not forward packets between them. This setting activates the routing engine, allowing the switch to perform Layer 3 forwarding between VLANs. A common exam trap is assuming that SVIs alone automatically enable routing. Many candidates overlook the need to enable the global "ip routing" command on Cisco multilayer switches. Practically, this means that even if SVIs show as up/up, hosts in different VLANs cannot communicate until IP routing is enabled, which activates the routing process and allows inter-VLAN traffic to flow.
KKey Concepts to Remember
- A multilayer switch uses SVIs as Layer 3 interfaces to route traffic between VLANs internally without external routers.
- SVIs being up/up indicates the VLAN interfaces are operational but does not guarantee inter-VLAN routing is active.
- IP routing must be enabled globally on a multilayer switch to activate Layer 3 forwarding between SVIs.
- Without enabling IP routing, the multilayer switch will not route packets between VLANs despite SVIs being up.
- Access ports connected to hosts remain in access mode and do not need to be converted to trunks for inter-VLAN routing.
- DHCP snooping does not affect the ability of SVIs to route traffic between VLANs and is unrelated to inter-VLAN routing.
- Removing VLAN assignments would disrupt network segmentation and prevent VLAN-based communication, so it is not a solution.
- Enabling IP routing on a multilayer switch is a fundamental step to allow inter-VLAN communication through SVIs.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
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More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
Question 1
A router learns the same prefix from both OSPF and EIGRP. Which route is installed by default?
Question 2
A router shows this output: R1#show ip ospf neighbor Neighbor ID Pri State Dead Time Address Interface 10.1.1.2 1 FULL/DR 00:00:34 192.168.12.2 GigabitEthernet0/0 10.1.1.3 1 2WAY/DROTHER 00:00:39 192.168.12.3 GigabitEthernet0/0 Which statement is correct?
Question 3
What is the OSPF metric called?
Question 4
A non-root switch has two uplinks toward the root bridge. One path has a lower total STP cost than the other. What role will the lower-cost uplink have?
Question 5
A router interface applies this ACL inbound: 10 deny tcp any any eq 80 20 permit ip any any A user reports that web browsing to a server by IP address fails, but ping works. Which statement best explains the behavior?
Question 6
A router learns route 198.51.100.0/24 from OSPF with AD 110 and also has a static route to the same prefix configured with AD 150. Which route is installed?
FAQ
Questions learners often ask
What does this 200-301 question test?
A multilayer switch uses SVIs as Layer 3 interfaces to route traffic between VLANs internally without external routers.
What is the correct answer to this question?
The correct answer is: IP routing must be enabled on the multilayer switch — If the SVIs are up but inter-VLAN traffic still fails, the most likely missing condition is that IP routing is not enabled on the multilayer switch. In plain language, the switch has the VLAN gateway interfaces present, but it has not been told to behave as a Layer 3 router between them. Without IP routing enabled, the SVIs can exist and still not actually route traffic between VLANs. This is a classic multilayer-switch design issue because many learners assume the presence of SVIs alone automatically creates routing. In reality, routed forwarding between VLANs still requires the switch to operate as a Layer 3 device. That is why enabling routing is the best answer.
What should I do if I get this 200-301 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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