JNCIP-ENT Exam Questions and Answers

You are configuring VSTP (VLAN Spanning Tree Protocol) on Juniper EX switches to interoperate with legacy third-party switches running PVST+. Which operational command allows you to verify the VSTP bridge identifier and root bridge status per VLAN?

When configuring advanced VLAN mapping on a Juniper MX Series router using flexible VLAN tagging, which term describes the action of replacing an incoming inner VLAN tag with a new tag before forwarding into the provider core?

You need to design a scalable Layer 2 architecture across multiple data center buildings using Juniper switches, avoiding single points of failure while preventing bridging loops. Which scaling mechanism allows Active-Active multihoming without running Spanning Tree Protocol across the core?

You are troubleshooting a Q-in-Q tunneling implementation on an MX Series router where customer VLAN tags are being stripped instead of preserved across the service provider core. Under which configuration hierarchy should the 'vlan-tagging' and 'pop-pop' or 'push' actions be applied on the interface?

An enterprise network engineer needs to configure a trunk port on a Juniper EX Series switch running Junos OS to allow multiple VLANs while explicitly blocking VLAN 99. Which configuration statement under 'interfaces ge-0/0/1 unit 0 family ethernet-switching' correctly achieves this?

You are configuring Q-in-Q tunneling on an MX Series router where customer frames arrive with VLAN tag 100, and you need to encapsulate them with a service provider outer VLAN tag 3000 using 'vlan-map'. Where is the VLAN map applied?

Which BGP community is a well-known transitive community used to prevent a route from being advertised outside of a local autonomous system?

A network engineer has configured BGP multipath on a Junos routing device using the 'multipath' statement under the routing-options bgp hierarchy. However, traffic is still only utilizing a single path. Which condition must be met for BGP multipath to become active for a destination prefix?

An administrator configures a BGP routing policy to match routes with community members using regex matching in Junos. Which statement accurately describes how Junos represents standard BGP communities in policy matching?

An administrator applies a policy containing 'as-path-prepend "65001 65001"' to outbound BGP updates sent to an external provider. What is the primary objective of this configuration?

Which command should an engineer use on a Junos device to verify whether a BGP next hop is successfully resolved via the routing table?

An enterprise network uses a BGP route reflector (RR) architecture where client routers reflect routes to each other. A non-client router sends a route with an Originator ID and Cluster List to the RR. How does the route reflector handle these attributes when reflecting the route to other clients?

When configuring a hierarchical scheduler map on an MX Series router, what is the primary purpose of the aggregate level shaping?

An administrator needs to implement a traffic conditioning profile on a Juniper MX Series router to limit traffic to a specific burst size and drop packets exceeding the rate. Which policing action parameter is required to ensure that exceeding traffic is dropped immediately without coloring?

Which standard Junos forwarding class is reserved for control plane traffic such as routing protocols and management traffic?

You need to ensure that delay-sensitive voice traffic is serviced before all other queues on an egress interface. Which scheduler property should you configure for the voice forwarding class?

You want to apply a rewrite rule on an outgoing interface to remark the DSCP bits of packets leaving your Juniper router. Where must this rewrite rule be applied within the CoS hierarchy?

Which command is used to verify the operational state of forwarding classes and their assigned queues on a specific interface on Junos?

An administrator is deploying EVPN multi-homing with all-active mode on an MX Series router. Which configuration element uniquely identifies the provider edge (PE) router's attachment circuit to an Ethernet segment?

You are troubleshooting a suboptimal traffic forwarding issue in an EVPN-VXLAN fabric with multi-homed devices. Traffic destined for a multi-homed server is being sent to only one of the PEs despite all-active mode being configured. Which EVPN route type and mechanism are responsible for enabling load balancing across all available PEs attached to the same Ethernet segment?

You are configuring a Junos EVPN-VXLAN environment where Type-3 (Inclusive Multicast Ethernet Tag) routes are being exchanged. A remote MX router is failing to establish ingress replication tunnels because it does not import the Type-3 route. Which configuration statement under the routing-instance is missing or misconfigured?

An administrator notices that broadcast, unknown unicast, and multicast (BUM) traffic sent from a local host is looping back to the originating multi-homed PE when using an all-active Ethernet segment. Which mechanism prevents this loop in EVPN?

During a maintenance window, an administrator needs to manually force a Designated Forwarder (DF) role change on a multi-homed Ethernet segment for an EVPN instance. Which parameter must be adjusted to influence the DF election algorithm in Junos OS?

When configuring VXLAN data plane encapsulation inside an EVPN routing instance on Junos OS, which logical interface type must be bound to the bridge domain to provide VXLAN VNI mapping?

An administrator notices that an EX4300 switch is supplying power using LLDP-MED power negotiation, but the IP phone is drawing more power than the initial hardware class allows. Where would you check the advertised LLDP-MED TLV power value received from the phone?

Which command allows you to verify the real-time PoE power consumption, allocated wattage, and operational status of all interfaces on an EX Series switch?

You are configuring a voice VLAN on an EX Series switch access port where an IP phone is connected in series with a PC. Which configuration is required on the switch interface to handle both tagged voice traffic and untagged data traffic?

An EX3400 switch experiences a total PoE power budget exhaustion after multiple high-power IP phones and security cameras are plugged in. You want to ensure that if a power deficit occurs, the switch immediately cuts power to lower-priority ports while maintaining power to executive phones on specific ports. How should you configure this?

What is the default behavior of an EX Series switch when an LLDP-MED capable IP phone connects and requests a network policy for voice VLAN?

You are troubleshooting an IP phone that is failing to discover its voice VLAN via LLDP-MED on an EX4600 switch. You issue the show lldp interface command and see that LLDP is transmitting properly, but the phone reports no voice VLAN TLV received. What is the most likely cause of this issue?

When configuring OSPFv3, which Junos address-family hierarchy is used to enable OSPFv3 on an interface?

You want to tune OSPF convergence by reducing the hello and dead intervals on a point-to-point interface. Which configuration is valid?

You are redistributing static routes into OSPF on a Junos device and want to assign a specific metric type to the resulting External LSAs. Where is this metric-type defined?

An OSPF area in your network contains multiple ABRs. You need to suppress the generation of Type-4 summary LSAs into a totally stubby area. How does Junos handle this natively?

Which Junos command displays the link-state database for OSPFv2, showing router LSAs and network LSAs?

An administrator needs to filter Type-3 LSAs entering an OSPF stub area on a Junos routing device. Which statement under the area hierarchy is required?

In an enterprise network running PIM sparse-mode, an engineer notices that multicast traffic is switched from the shared tree (*,G) to the source-specific tree (S,G) prematurely, causing micro-bursts on core links. Which command disables this automatic switchover behavior on a Junos router?

An enterprise network uses PIM sparse-mode across multiple routing instances. An administrator notices that source registration messages are looping between the designated router (DR) and the RP. Which configuration statement under [edit protocols pim] will prevent the DR from continuously encapsulating and sending register messages when no receivers are joined?

An engineer wants to restrict IGMP membership reports to only accept version 2 on a specific VLAN interface configured on an MX Series router. Which configuration statement achieves this requirement?

A network administrator needs to display the multicast routing table entries, including incoming interfaces and outgoing interface lists (OIL), on a Junos device. Which operational command should be used?

An administrator wants to configure MSDP (Multicast Source Discovery Protocol) between two autonomous system border routers to share active source information. Which configuration hierarchy in Junos is used to define the MSDP peer relationship?

An enterprise design requires configuring an Anycast RP setup using two Junos routers to provide redundancy for PIM sparse-mode. Which mechanism is required to synchronize source state information between the two Anycast RPs within the same AS?

What is the primary function of the RADIUS server attribute 'Tunnel-Medium-Type' (Attribute 65) when received during an 802.1X authentication exchange on an EX Series switch?

Which command allows an administrator to verify the active supplicant states and authentication status on a specific EX Series switch interface?

You are troubleshooting an 802.1X deployment on an EX4300 switch. Clients fail to authenticate when using Supplicant-based authentication combined with MAC RADIUS fallback. You notice that the switch does not attempt MAC RADIUS after 802.1X times out. Which configuration error most likely caused this?

An enterprise network administrator needs to configure 802.1X authentication on EX Series switches. Which statement is correct regarding the default behavior of the supplicant timeout timer?

You are implementing MAC RADIUS authentication on an EX4600 switch. You notice that when a device connects, the switch sends the MAC address in the Username attribute (RADIUS attribute 1) with hyphen separators (e.g., aa-bb-cc-dd-ee-ff). Your RADIUS server expects colons (aa:bb:cc:dd:ee:ff). Where must you configure this format change on Junos OS?

You are configuring a captive portal on an EX Series switch. You want to ensure that specific management traffic and critical server subnets are accessible to clients *before* they authenticate through the captive portal. Which configuration feature accomplishes this?