350-601 Network Practice Test 9 — 15 Questions

Question 1

A network engineer is configuring a Cisco Nexus 9000 Series switch as a VXLAN tunnel endpoint in an EVPN fabric. The underlay uses OSPF and the overlay uses iBGP EVPN. The engineer notices that remote MAC addresses are learned, but traffic to a remote host is dropped. The output of show nve peers shows the remote VTEP in an Up state. Which action should the engineer take to resolve the issue?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Confirm that the Layer 2 VNI is mapped to the correct VLAN and that the VLAN is allowed on the trunk toward the local host.. When NVE peers are Up and remote MACs are learned, the control plane is healthy. A common cause of dropped traffic is a local configuration issue such as a missing VLAN-to-VNI mapping or a VLAN not permitted on the host-facing trunk. Verifying those elements ensures the local host traffic is correctly encapsulated and forwarded into the VXLAN overlay.

Answer

Increase the MTU on the underlay interfaces to accommodate the VXLAN encapsulation overhead.

Answer

Check the BGP EVPN route-target configuration to ensure the Layer 3 VNI is imported into the correct VRF.

Answer

Verify that the NVE source interface is reachable and that the VXLAN UDP port 4789 is permitted in the underlay.

Question 2

A data center engineer is troubleshooting intermittent connectivity between two servers in different VLANs. The servers are connected to different leaf switches in a VXLAN EVPN fabric. When checking the fabric, the engineer notices that the NVE interface on one leaf is up/up but the VNI for the server VLAN is not listed in 'show nve vni'. What is the most likely cause?

Accepted Answer

The VLAN-to-VNI mapping is missing under the VLAN configuration. The NVE interface being up/up indicates the overlay tunnel is operational, but the absence of the VNI in 'show nve vni' means the VNI is not instantiated on the NVE. This typically occurs when the VLAN-to-VNI mapping is missing under the VLAN configuration (e.g., 'vlan 100' then 'vn-segment 10100'), which prevents the VNI from being associated with the NVE interface and advertised via BGP EVPN.

Answer

MTU mismatch on the underlay network

Answer

Anycast gateway is not configured on the leaf

Answer

BGP EVPN peers are not established

Question 3

A network engineer is configuring OSPF on a Cisco Nexus switch for a data center network. The requirement is to ensure that the switch does not become the Designated Router (DR) on a multi-access segment. Which OSPF configuration achieves this?

Accepted Answer

Set OSPF priority to 0 on the interface. Setting the OSPF priority to 0 on the interface prevents the switch from participating in the DR/BDR election process, ensuring it will never become the Designated Router (DR) or Backup Designated Router (BDR) on a multi-access segment. This is the standard method per RFC 2328 to make a router ineligible for DR/BDR status while still allowing it to form full adjacencies with the DR and BDR.

Answer

Set OSPF priority to 255 on the interface

Answer

Change the OSPF network type to point-to-point

Answer

Configure the interface as passive under OSPF

Question 4

During a maintenance window, a network engineer plans to upgrade the NX-OS software on a pair of Nexus 9000 switches configured as vPC peers. The engineer wants to minimize traffic disruption. Which upgrade sequence is recommended?

Accepted Answer

Upgrade the secondary vPC peer first, then the primary. In a vPC pair, the secondary peer is upgraded first to preserve the primary's role as the forwarding anchor. Upgrading the secondary peer allows it to reboot and rejoin the vPC domain without disrupting the data plane because the primary peer continues to forward traffic. Once the secondary is stable, the primary is upgraded, ensuring minimal traffic loss.

Answer

Upgrade both switches simultaneously using ISSU

Answer

Reload both switches to a previous version, then upgrade

Answer

Upgrade the primary vPC peer first, then the secondary

Question 5

Which TWO statements about VXLAN BGP EVPN control plane are true? (Choose two.)

Accepted Answer

The underlay network provides IP connectivity between VTEPs. The VXLAN underlay network (typically an IP-based fabric using protocols like OSPF or IS-IS) provides IP connectivity between VTEPs, enabling them to encapsulate and decapsulate VXLAN packets. Without this underlay reachability, VTEPs cannot communicate, making it a foundational requirement for VXLAN operation.

Answer

VXLAN encapsulates Ethernet frames in IP packets using MPLS labels

Answer

VXLAN uses a 32-bit network identifier (VNI)

Answer

The control plane is responsible for actual data forwarding

Question 6

Refer to the exhibit. An engineer is configuring a server-facing interface on a Nexus switch. The server is running VMware ESXi with multiple virtual machines in VLANs 10, 20, and 30. After applying the configuration, the ESXi host reports that it cannot communicate on VLAN 30. Which configuration change should be made?

Accepted Answer

Create VLAN 30 in the global VLAN database. VLAN 30 must exist in the global VLAN database before it can be used on any interface. Even though the interface configuration allows VLAN 30 as a trunked VLAN, the switch will not forward traffic for a VLAN that has not been created globally. Without the 'vlan 30' command in global configuration mode, the VLAN is not present in the switch's VLAN database, and the interface will not pass traffic for that VLAN.

Answer

Remove the 'spanning-tree port type edge trunk' command

Answer

Change the native VLAN to 30

Answer

Configure the port as an access port in VLAN 30

Question 7

Refer to the exhibit. A VXLAN VNI (10030) is operationally down. What is the most likely cause?

Accepted Answer

The VLAN associated with VNI 10030 is not configured or mapped. VXLAN VNI 10030 is operationally down because the VLAN that maps to this VNI is either not created or not associated with the VNI under the NVE interface. In Cisco NX-OS, a VNI becomes operationally up only when the corresponding VLAN exists and is properly mapped via the `member vni 10030 associate-vrf` or `member vni 10030` command under the NVE interface. Without this mapping, the NVE cannot forward traffic for that VNI, leaving it in a down state.

Answer

The source interface loopback0 is not up

Answer

The NVE mode should be L2VPN instead of L3VPN

Answer

The multicast group 239.1.1.1 is not reachable

Question 8

An engineer is troubleshooting connectivity between two Nexus 9000 switches configured with vPC. The vPC peer link is up, but the vPC peer-keepalive link is failing. Which action should be taken to ensure vPC convergence in the event of a peer-link failure?

Accepted Answer

Ensure the peer-keepalive link uses a dedicated management interface or a separate VRF.. When the vPC peer link fails, the peer-keepalive link is used by the secondary switch to detect that the primary is still alive and to avoid becoming the primary (which would cause a split-brain scenario). Using a dedicated management interface or a separate VRF ensures the keepalive messages are isolated from the data plane and remain reachable even if the peer link goes down, allowing the secondary to correctly keep its vPC member ports in a suspended state and maintain convergence.

Answer

Disable vPC on both switches and reconfigure the port channels.

Answer

Reconfigure the vPC domain with a lower priority on the secondary switch.

Answer

Increase the vPC peer-keepalive hold timeout to 5 seconds.

Question 9

A network engineer is implementing QoS on a Nexus 9000 switch. The requirement is to prioritize storage traffic (iSCSI) and ensure lossless behavior. Which queuing strategy should be applied to the egress interface?

Accepted Answer

Priority Flow Control (PFC) with a no-drop queue for iSCSI.. Priority Flow Control (PFC) is the IEEE 802.1Qbb mechanism designed to provide lossless behavior for specific traffic classes, such as iSCSI storage traffic, on Nexus 9000 switches. By creating a no-drop queue for iSCSI, PFC uses pause frames on a per-priority basis to prevent buffer overflow, ensuring zero packet loss required by storage protocols.

Answer

Tail drop with DSCP-based classification.

Answer

Weighted Round Robin (WRR) with three queues.

Answer

Policing at the ingress and marking at the egress.

Question 10

An organization is deploying a new leaf-spine fabric with Cisco ACI. The requirement is to allow inter-tenant communication between two EPGs in different tenants. Which configuration object is necessary to enable this communication?

Accepted Answer

A shared contract between the two EPGs.. In Cisco ACI, inter-tenant communication between EPGs in different tenants requires a shared contract. A contract defines the rules (filters) that permit traffic between EPGs, and when it is marked as 'shared,' it can be consumed by EPGs across tenant boundaries. This allows the provider EPG in one tenant to expose services to a consumer EPG in another tenant without merging the tenants' VRFs or bridge domains.

Answer

A common VRF that spans both tenants.

Answer

A filter that permits the required traffic.

Answer

A bridge domain that connects both EPGs.

Question 11

Arrange the steps to create a service profile template in Cisco UCS Manager.

Accepted Answer

Create UUID Suffix Pool, then Create vNIC Template, then Create Service Profile Template (referencing the pool and vNIC template), then Associate with a Server Pool. Service profile template requires UUID pool, vNIC template, profile creation, server pool association, and assignment.

Answer

Create vNIC Template, then Create UUID Suffix Pool, then Create Service Profile Template, then Associate with a Server Pool

Answer

Create Service Profile Template, then Create UUID Suffix Pool, then Create vNIC Template, then Associate with a Server Pool

Answer

Associate with a Server Pool, then Create UUID Suffix Pool, then Create vNIC Template, then Create Service Profile Template

Question 12

Match each Cisco UCS Manager CLI command to its function.

Accepted Answer

scope server: Enters server management mode. In UCS Manager CLI, 'scope server' enters server management mode, 'scope chassis' enters chassis management mode, and 'show environment' displays environmental status. Other commands like 'scope fabric-interconnect' or 'show server' have different functions.

Answer

scope server: Enters chassis management mode

Answer

scope chassis: Enters server management mode

Answer

show environment: Displays server inventory

Question 13

A network engineer is configuring a VPC peer-link on a Nexus switch. Which interface configuration is required for the peer-link port-channel?

Accepted Answer

switchport mode trunk. A VPC peer-link is a special port-channel that carries control traffic (e.g., Cisco Fabric Services over Ethernet) and data traffic between VPC peer switches. It must be configured as a trunk (switchport mode trunk) to allow multiple VLANs, including the VPC VLAN and the peer-keepalive link VLAN, to traverse the link. Without trunk mode, the peer-link cannot properly forward the necessary VLAN traffic for VPC operation.

Answer

spanning-tree port type edge trunk

Answer

switchport mode access

Answer

no switchport

Question 14

In a VXLAN EVPN fabric, which protocol is used to exchange MAC and IP address reachability information among VTEPs?

Accepted Answer

BGP. In a VXLAN EVPN fabric, BGP (Border Gateway Protocol) is used as the control plane protocol to exchange MAC and IP address reachability information among VTEPs. Specifically, MP-BGP (Multiprotocol BGP) with EVPN address family (AFI L2VPN / SAFI EVPN) carries Type-2 routes (MAC/IP advertisement) to distribute host reachability across the overlay network, enabling efficient MAC learning and ARP suppression.

Answer

IS-IS

Answer

EIGRP

Answer

OSPF

Question 15

A network engineer is troubleshooting an OSPF adjacency issue between two Nexus switches. The neighbors are stuck in the EXSTART state. What is the most likely cause?

Accepted Answer

MTU mismatch. When OSPF neighbors are stuck in the EXSTART state, the most common cause is an MTU mismatch. In EXSTART, the routers exchange Database Description (DBD) packets, which must be no larger than the interface MTU. If one interface has a smaller MTU, the DBD packet is dropped, preventing the adjacency from progressing to the Exchange state. Cisco Nexus switches default to an MTU of 1500 bytes, but any mismatch will cause this issue.

Answer

Hold timer mismatch

Answer

Incorrect area ID

Answer

Duplicate router ID