350-601 Network Practice Test 10 — 15 Questions

Question 1

Which statement is true about the VLANs carried on a VPC peer-link?

Accepted Answer

The peer-link carries all VLANs that are allowed on the trunk interface.. In a vPC domain, the peer-link is a special trunk that carries all VLANs allowed on the trunk interface, including those not present on any member port. This ensures that orphaned traffic (traffic arriving on the peer-link destined for a device connected to the other vPC peer) can be forwarded correctly. The peer-link must carry all VLANs to maintain Layer 2 connectivity and loop-free behavior without relying on spanning tree.

Answer

The peer-link carries only the VLANs allowed on the member interfaces.

Answer

The peer-link requires spanning-tree port type edge trunk configuration.

Answer

The peer-link must be configured as a layer 3 interface.

Question 2

In a centralized anycast gateway VXLAN EVPN design, which is a requirement?

Accepted Answer

All VTEPs share a common anycast IP address for the default gateway.. In a centralized anycast gateway VXLAN EVPN design, all VTEPs share a common anycast IP address and MAC address for the default gateway. This allows any VTEP to serve as the first-hop router for hosts, enabling optimal east-west traffic forwarding without requiring a separate gateway device. The anycast IP is configured on each VTEP's VLAN interface, and the same IP/MAC is advertised via EVPN Type-2 routes.

Answer

Each VTEP has a unique anycast IP address.

Answer

The anycast gateway is configured on the spine switches.

Answer

The route reflector is an external BGP speaker.

Question 3

A network engineer notices that when a host sends a packet to a destination on a different VTEP, the packet is flooded to all VTEPs even though the destination MAC is known. What is the most likely cause?

Accepted Answer

The BGP EVPN route table is missing the MAC/IP route for the destination.. In a BGP EVPN VXLAN fabric, when a host sends a packet to a known destination MAC on a different VTEP, the ingress VTEP should perform MAC/IP route lookup in the BGP EVPN route table to determine the correct remote VTEP. If the MAC/IP route for the destination is missing (e.g., not advertised or withdrawn), the ingress VTEP has no mapping to a remote VTEP and must flood the packet to all VTEPs in the VNI, causing unnecessary broadcast traffic. This is the most likely cause of the described behavior.

Answer

The VNI is misconfigured.

Answer

The MTU exceeds 1500 bytes.

Answer

ARP suppression is disabled.

Question 4

Which command displays the VLANs allowed on a trunk interface?

Accepted Answer

show interface trunk. The 'show interface trunk' command displays trunk parameters, including the VLANs allowed on the trunk interface. This command shows the trunking mode, encapsulation (e.g., 802.1Q), and the allowed VLAN list for each trunk port. It is the direct command to verify which VLANs are permitted on a specific trunk link.

Answer

show running-config interface

Answer

show vlan

Answer

show interface switchport

Question 5

A network engineer is verifying VPC configuration on a pair of Nexus switches. Which two commands should be used to check VPC status and consistency? (Choose two.)

Accepted Answer

show vpc consistency-parameters. (show vpc) is correct because it displays the overall VPC status, including the local and peer VPC system MAC, role, and the operational state of each VPC member port. Option B (show vpc consistency-parameters) is correct because it verifies that critical parameters (e.g., STP mode, VLAN interfaces, MTU) are consistent between the two VPC peers, which is essential for VPC to function correctly and avoid traffic black-holing.

Answer

show vpc role

Answer

show vpc peer-keepalive

Answer

show vpc statistics

Question 6

Refer to the exhibit. What is the current state of the VPC domain?

Accepted Answer

Operational. The exhibit shows the output of 'show vpc' with the vPC domain ID set to 100, the peer-keepalive link status as 'Active', and the peer-link status as 'up'. The vPC role is 'primary' and the operational status is listed as 'operational', which indicates that the vPC domain is fully functional and all consistency checks have passed. Therefore, the current state is operational.

Answer

VPC domain not configured

Answer

Peer-link down

Answer

Consistency check failed

Question 7

Refer to the exhibit. What is the most likely cause of the NVE interface being down?

Accepted Answer

The source interface is not configured.. The NVE (Network Virtualization Edge) interface requires a valid source interface (typically a loopback) to establish VXLAN tunnels. If the source interface is not configured under the NVE interface, the interface remains in a down state because it cannot form VXLAN overlay adjacencies. This is the most common cause of an NVE interface being down in Cisco NX-OS.

Answer

The VXLAN destination UDP port is incorrect.

Answer

The overlay VLAN is not configured.

Answer

The VNI list is empty.

Question 8

An engineer is designing a Layer 3 network for a data center using OSPF. The core switches are connected to aggregation switches. To optimize convergence, which OSPF network type should be used on the links between core and aggregation?

Accepted Answer

point-to-point. In a data center spine-leaf architecture, the links between core (spine) and aggregation (leaf) switches are typically point-to-point Layer 3 links. Configuring OSPF network type point-to-point (option D) on these interfaces eliminates the need for DR/BDR election, reduces hello and dead timers (default 10s/40s vs 30s/120s for broadcast), and allows faster convergence because OSPF immediately forms a neighbor adjacency without waiting for election delays.

Answer

broadcast

Answer

non-broadcast

Answer

point-to-multipoint

Question 9

Which two VXLAN control plane options are supported on Cisco Nexus 9000 switches? (Choose two.)

Accepted Answer

Multicast. VXLAN on Cisco Nexus 9000 switches supports both multicast-based control plane (using IGMP/PIM to flood BUM traffic) and MP-BGP EVPN (RFC 7432) as the control plane for distributing MAC/VTEP reachability. Multicast is the traditional method for handling BUM traffic in VXLAN fabrics, while MP-BGP EVPN provides a more scalable, standards-based control plane with host route advertisement and multi-tenancy.

Answer

OTV

Answer

Static VXLAN tunnel

Answer

OpenFlow

Question 10

Refer to the exhibit. A network engineer notices that traffic for VNI 10000 is not being encapsulated. What is the most likely reason?

Accepted Answer

VNI 10000 is not configured under the nve interface.. VNI 10000 must be explicitly mapped to an NVE interface under the 'interface nve1' configuration using the 'member vni 10000' command. Without this mapping, the NVE interface does not know which VNI to encapsulate traffic for, even if the VNI exists in the network. Option B correctly identifies this missing configuration as the most likely cause.

Answer

BGP EVPN is not configured.

Answer

The VRF association is incorrect.

Answer

The source-interface is not reachable.

Question 11

Refer to the exhibit. What is the most likely cause of neighbor 10.1.1.3 being stuck in EXSTART?

Accepted Answer

MTU mismatch between the interfaces.. In OSPF, the EXSTART state indicates that neighbors are negotiating the master/slave relationship and exchanging Database Description (DBD) packets. If the MTU of the interface on one side is larger than the MTU on the other, the larger DBD packet will be silently dropped, preventing the neighbor from progressing past EXSTART. This is a classic symptom of an MTU mismatch, as the OSPF adjacency will remain stuck in EXSTART or EXCHANGE.

Answer

Duplicate router ID.

Answer

OSPF network type mismatch.

Answer

The interface is configured as passive.

Question 12

A data center uses VPC between two Nexus switches. Which statement is true about the VPC peer-link?

Accepted Answer

It carries both data and control traffic.. The VPC peer-link is a critical component in a vPC domain, carrying both data traffic (e.g., traffic from orphan ports or traffic that must traverse the peer-link for forwarding) and control traffic (e.g., vPC keepalive messages and Cisco Fabric Services (CFS) synchronization). This dual role ensures that the two Nexus switches operate as a single logical entity for the downstream devices, providing loop-free Layer 2 multipathing.

Answer

It must be a single link.

Answer

It carries only control traffic.

Answer

It is used only for orphan ports.

Question 13

A network engineer is troubleshooting a VXLAN EVPN problem where some endpoints are not reachable. The output of 'show bgp l2vpn evpn' shows Type-3 routes but no Type-2 routes for a specific VNI. What should the engineer check?

Accepted Answer

The VLAN corresponding to the VNI has no active ports.. Type-3 routes (IMET routes) are used for BUM traffic forwarding and are advertised when the VNI is configured under the NVE interface, even if no endpoints are active. Type-2 routes (MAC/IP advertisement routes) are only generated when the switch learns a MAC address on a VLAN associated with that VNI. If Type-3 routes exist but Type-2 routes are missing, the VNI is correctly configured for the overlay, but no active ports in the corresponding VLAN are learning MAC addresses, preventing Type-2 route generation.

Answer

The route-target import/export is misconfigured.

Answer

BGP session is not established.

Answer

The VNI is not configured under the NVE interface.

Question 14

In a Cisco ACI fabric, a new EPG is created and associated with a bridge domain that has 'Unicast Routing' enabled. However, endpoints in that EPG cannot communicate with endpoints in other EPGs in the same VRF. What is missing?

Accepted Answer

A contract between the EPGs. In Cisco ACI, communication between EPGs within the same VRF is not allowed by default; it requires a contract. A contract defines the policies (allow/deny) and filters for traffic between EPGs. Without a contract, all traffic is dropped, even if the bridge domain has unicast routing enabled. Option C is correct because the missing element is the contract that explicitly permits inter-EPG communication.

Answer

The EPG must be attached to a Layer 3 outside

Answer

The bridge domain must have 'L3 Unknown Multicast Flooding' set

Answer

A route leak between bridge domains

Question 15

An engineer is troubleshooting BGP EVPN control plane. They issue 'show bgp l2vpn evpn' and see Type-3 routes but no Type-2 routes for any VNI. Which condition is most likely?

Accepted Answer

The VTEP has not learned any MAC addresses. Type-3 routes (Inclusive Multicast Ethernet Tag routes) are generated automatically when an EVPN VNI is configured, regardless of MAC learning. Type-2 routes (MAC/IP Advertisement routes) are only generated after the VTEP learns MAC addresses from data-plane traffic or from local endpoints. The absence of Type-2 routes with Type-3 present indicates the VTEP has not yet learned any MAC addresses for that VNI.

Answer

The overlay VNI is not mapped to a VLAN

Answer

The BGP neighbor is not from the same AS

Answer

The EVPN address-family is not enabled