JN0-650 Exam Dumps - Enterprise Routing and Switching - Professional (JNCIP-ENT)

The exhibit shows the MSTP configuration for two switches,switch1andswitch2. MSTP allows you to group multiple VLANs into a single Multiple Spanning Tree Instance (MSTI), enabling different root bridges and topologies for different sets of VLANs.

Root Bridge Election (Option B):For any Spanning Tree instance, the switch with thelowest bridge priorityis elected as the root bridge.

Formsti 2, switch1 has a priority of4k(4096), while switch2 has a priority of8k(8192).

Since 4096 < 8192,switch1 is elected the root bridge for msti 2.

Failover Behavior (Option D):Spanning Tree is designed for redundancy. If a primary root bridge fails, the remaining switches in the network re-elect a new root based on the next lowest priority.

Ifswitch2goes down, switch1 becomes the only switch in the region.

Regardless of its original priority (4k or 8k), switch1 will take over as theroot bridge for both msti 1 and msti 2because there are no other contenders with a better (lower) priority.

Incorrect Statements:Option Ais incorrect because for msti 1, switch2 has the lower priority (4k vs. 8k), making switch2 the root bridge.Option Cis incorrect because it contradicts the fundamental high-availability nature of Spanning Tree.

When integrating a QFX Series switch into an EVPN-VXLAN IP fabric, specific BGP and EVPN hierarchy configurations are required to establish the control and data planes:

EVPN Encapsulation (Option A):In Junos OS, the encapsulation vxlan statement must be explicitly configured under the protocols evpn hierarchy. This defines that the EVPN control plane will use VXLAN as the data plane encapsulation method rather than MPLS.

BGP Address Family (Option C):EVPN uses Multiprotocol BGP (MP-BGP) to distribute reachability information. For the control plane to function, you must enable the EVPN signaling address family under the BGP protocol using the command set protocols bgp group family evpn signaling.

Incorrect Options:Option Bis incorrect because family vpls is used for traditional VPLS signaled by BGP, not for EVPN-VXLAN.Option Dis incorrect because while the loopback interface must be reachable, it is typically advertised via anIGP(like OSPF or IS-IS) to provide the underlay connectivity that BGP then rides upon; BGP itself does not "advertise" the loopback to establish the initial peerings.

OSPF (Open Shortest Path First) is a standards-based Link-State Interior Gateway Protocol (IGP) implemented within Junos OS 24.4:

Intra-AS Routing:OSPF is designed to distribute routing information and performneighbor discovery within a single Autonomous System (AS). It divides the AS into areas to localize Link-State Advertisements (LSAs) and reduce the size of the Link-State Database (LSDB) on each router. (Option B)

Algorithm:OSPF uses theShortest Path First (SPF) or Dijkstra algorithm, not a distance vector algorithm (which would be RIP or BGP). This makesOption Aincorrect.

Directly Connected Routes:In Junos OS, you must explicitly configure an interface under the [edit protocols ospf] hierarchy to include it in the OSPF process. Once an interface is added, its prefix isautomatically advertisedto neighbors via Router (Type 1) LSAs. This makesOption Ctechnically inaccurate in the context of interfaces participating in the protocol.

Scope:Protocols used between multiple autonomous systems are External Gateway Protocols (EGPs), such as BGP. This makesOption Dincorrect.