JN0-460 Exam Dumps - Juniper JNCIS-MistAI Questions and Answers

In Juniper Mist, thesyslogfeature allows administrators to forward event messages and alerts from the Mist cloud to an external syslog server.

This is often used for centralized event monitoring, compliance, and correlation with tools like Splunk or SIEM systems.

Syslog operates over UDP or TCP and can capture switch events, system logs, and Marvis actions for both Wired and Wireless networks.

According to Juniper Networks' EVPN-VXLAN documentation, devices that perform the encapsulation and de-encapsulation of Ethernet frames into VXLAN UDP packets at the edge of the network are known as Virtual Tunnel Endpoints (VTEPs)1111. In the context of a campus fabric overlay, these devices often function as L2 gateways when they bridge traditional Layer 2 traffic from end-user devices across a Layer 3 IP fabric.

The exhibit demonstrates a 3-stage IP Clos architecture where access1 and access3 are explicitly identified as VTEP endpoints. A VXLAN tunnel is shown originating at access1 and terminating at access3, allowing "User1" and "Server1"—both located on the same 10.1.1.0/24 subnet—to communicate as if they were on the same physical Layer 2 segment despite being separated by a Layer 3 IP Fabric (172.16.0.0/24). In this scenario, access1 and access3 fulfill the L2 gateway role by mapping the local VLAN traffic to a specific VXLAN Network Identifier (VNI) for transport across the underlay3.

As L2 gateways, these switches maintain the bridge table for the overlay network, learning MAC addresses from local ports and via the EVPN control plane from remote VTEPs4. This architecture allows for seamless Layer 2 mobility and connectivity across complex routed infrastructures while eliminating the need for Spanning Tree Protocol (STP) in the core5555. In contrast, options like "VNI" refer to the segment ID itself rather than a device role, and "root bridge" refers to an STP-specific role that EVPN-VXLAN is designed to move away from in a modern fabric.

InJuniper Mist Cloud, configuration hierarchy includesorganization-level templates,site-level configurations, andindividual switch configuration. Site and organization levels provide shared settings, while per-device details such as hostname or role are set individually.

“Device-specific attributes such as hostname, role, or management IP are configured under the individual switch configuration menu. Templates and site configurations apply globally, while individual configurations override device-level parameters.”

Option A:Incorrect — site configuration applies to all switches at a site, not unique details.

Option B:Incorrect — CLI configuration is not used when switches are managed by Mist Cloud.

Option C:Correct— each switch’s name and role are configured individually underSwitches → Switch Configuration.

Option D:Incorrect — organization templates define global settings, not per-switch names.

Aport negotiation mismatchoccurs when the local and remote interfaces fail to agree on common speed or duplex settings.

Marvis Wired Assurance automatically detects this by analyzing telemetry from the switch’s physical interfaces.

You can resolve this by ensuringauto-negotiationis enabled on both ends (A) and verifying the peer device supports the802.3 autonegotiation standard(D).

Manually forcing half-duplex or replacing hardware is unnecessary unless the hardware is faulty.

“Marvis Wired Actions correlate interface negotiation errors with LLDP neighbor data to pinpoint mismatched configurations, helping administrators quickly verify speed/duplex compatibility and 802.3 autonegotiation support.”

In anEVPN-VXLANarchitecture, theVXLAN Tunnel Endpoint (VTEP)is responsible for encapsulating and de-encapsulating Layer 2 Ethernet frames into VXLAN packets that traverse the IP underlay.

“Each device participating in a VXLAN overlay operates as a VXLAN Tunnel Endpoint (VTEP). The VTEP encapsulates Ethernet frames into VXLAN headers for transmission and de-encapsulates VXLAN packets back into Ethernet frames upon receipt.”

Option A:Incorrect — VLAN is a Layer 2 construct, not responsible for encapsulation.

Option B:Correct— VTEP handles VXLAN encapsulation and de-encapsulation.

Option C:Incorrect — root bridge pertains to STP, not VXLAN.

Option D:Incorrect — WXLAN policy is not a valid networking term in Juniper documentation.

According to the Juniper Mist Wired Assurance Configuration Guide, the foundational step for implementing Layer 2 segmentation within the Mist UI is the creation of a "Network". In the context of Mist Wired Assurance, a Network is logically synonymous with a Virtual Local Area Network (VLAN). To define a network, a user must navigate to the Networks section—located within an organization-level template, a site-level configuration, or an individual switch configuration—and click to add a new entry.

The two mandatory parameters for this step are naming the VLAN and providing the corresponding VLAN ID. The name serves as a human-readable alias (such as "Corporate_Data" or "IoT_Devices") that allows administrators to easily reference the segment across different parts of the configuration without constantly tracking numeric IDs. The VLAN ID is the specific numeric value (ranging from 1 to 4094) that will be used by the switch for 802.1Q tagging on the physical wire.

This step is a prerequisite for more advanced configurations. Once a network is created with its name and ID, it can then be selected within a Port Profile. While creating a port profile (Option C) or an access policy (Option D) are common tasks in the deployment workflow, they are dependent on the prior existence of a defined Network. For instance, a Port Profile defines how a port behaves (e.g., access vs. trunk), but it must point to a specific Network name to know which VLAN to assign to that interface. Similarly, site variables can be used to override these VLAN IDs at specific locations, but the base definition requires the initial pairing of a name and a default ID in the portal.

In acore-distribution campus fabricmodel, the EVPN-VXLAN overlay is establishedonly between the core and distribution tiers. Theaccess switches are not part of the EVPN fabric; they connect upstream to distribution but do not run VXLAN tunnels.

“In the core-distribution campus fabric, only the core and distribution layers participate in the EVPN-VXLAN topology. The access layer connects to the distribution switches and forwards traffic but does not take part in the EVPN-VXLAN fabric.”

Option A:Correct — EVPN-VXLAN is built between core and distribution tiers.

Option B:Incorrect — both coreand distributionparticipate, not just core.

Option C:Incorrect — access switches are excluded from EVPN-VXLAN participation.

Option D:Correct — the access layer does not participate in EVPN-VXLAN.

According to Juniper Networks' validated designs for campus fabrics, the campus fabric core-distribution with edge-routed bridging (ERB) is the optimal architecture when high volumes of east-west traffic are present and access switches are restricted to Layer 2 operations. In an ERB design, the EVPN-VXLAN fabric extends from the core switches to the distribution switches.1 The critical differentiator is the placement of the default gateways (Integrated Routing and Bridging or IRB interfaces). In the ERB model, these gateways are moved from the core to the distribution layer, which effectively acts as the "edge" of the EVPN fabric.

By placing the Layer 3 gateways at the distribution layer, inter-VLAN (east-west) traffic is routed closer to the endpoints.2 This prevents the "hairpinning" effect found in Centrally-Routed Bridging (CRB) architectures, where traffic must travel all the way to the core layer to be routed between subnets before returning down to the distribution and access layers. This reduction in latency and core-link utilization is essential for modern campus environments with high server-to-server or client-to-client traffic patterns.

Furthermore, this architecture specifically accommodates Layer 2 access switches. In the ERB core-distribution model, the access switches are not part of the EVPN-VXLAN overlay; instead, they connect to the distribution tier using standard Link Aggregation Control Protocol (LACP) or ESI-LAG. This allows organizations to leverage existing legacy or lower-tier access switches that do not support advanced VXLAN capabilities while still benefiting from a robust, scalable EVPN-VXLAN fabric at the distribution and core layers.5 In contrast, while the campus fabric IP Clos also excels at handling east-west traffic, it requires the access switches themselves to perform VXLAN encapsulation/decapsulation (acting as VTEPs), which contradicts the requirement for access switches to operate only at Layer 2.

According to theJuniper Mist AI for Wired – Campus Fabric IP Clos Deployment Workflow, deploying a campus fabric involves a defined sequence of planning and configuration steps within the Mist Cloud interface. The key stages include:

“To deploy a campus fabric, you must first define the topology type, identify the physical connections between devices, and define the networks of interest that will be extended across the fabric.”

Breaking this down:

Choose the topology (D):Selecting the correct fabric type (3-Stage or 5-Stage IP Clos) determines how access, distribution, and core switches will interconnect.

Define the physical connections (A):This step involves specifying the uplink and downlink relationships between switches so that Mist can auto-generate EVPN-VXLAN and routing configurations.

Define the networks of interest (B):These are the VLANs and subnets that need to be extended across the fabric for user and device connectivity.

Steps such asconfiguring DNS serversordefining GBP tagsarenot part of the campus fabric deployment workflowin Mist Wired; they are optional or separate configurations outside the main deployment flow.

During campus fabric deploymentin Mist AI, switches are onboarded usingclaim codesand must beassigned to the correct siteandonlineso that Mist can push configurations and validate connectivity.

“All switches to be included in a campus fabric must be claimed, online, and assigned to the target site before launching the Campus Fabric wizard. Mist Cloud automatically discovers their roles and builds the topology.”

Option A:Incorrect — switches must be site-assigned before fabric creation.

Option B:Correct— switches must beonlineto receive configurations from Mist.

Option C:Incorrect — offline devices cannot be configured or validated in the fabric wizard.

Option D:Correct— switches must beassigned to the correct sitefor topology creation.