Juniper JN0-682 Practice Test - Questions Answers, Page 5

One of the primary advantages of EVPN (Ethernet VPN) over VPLS (Virtual Private LAN Service) is the capability of mass MAC withdrawal (A). This feature allows EVPN to quickly remove MAC addresses from the forwarding database when a link or node fails, improving convergence times and network stability. In contrast, VPLS lacks this efficient mechanism for withdrawing MAC addresses en masse, which can lead to slower convergence and potential traffic blackholing in the event of network changes or failures.

Reference:

Juniper Networks - EVPN Overview

Understanding EVPN

For enabling visibility into EVPN-VXLAN network traffic through continuous monitoring:

You must enable sFlow monitoring on each interface individually (Option C): sFlow is a sampling technology used for monitoring network traffic. In a Juniper environment, sFlow needs to be enabled on individual interfaces to start collecting traffic samples. This allows for granular control over which interfaces are monitored.

You cannot enable sFlow monitoring on each interface individually (Option A): This statement is incorrect, contradicting the above explanation. sFlow can and should be enabled on specific interfaces as needed.

The option stating that the sFlow agent needs to be manually installed on QFX Series switches (Option D) is inaccurate, as the sFlow feature is typically integrated into the Junos OS running on QFX Series switches. The statement about the sFlow agent being installed by default on QFX Series switches (Option B) is partially true but does not directly address the question of enabling visibility into network traffic.

Reference

Juniper Networks: Configuring sFlow Technology for Network Monitoring

https://www.juniper.net/documentation/us/en/software/junos/ovsdb-vxlan-qfx/topics/example/overlay-ping-traceroute-vxlan.html

In a scenario where RSVP and LDP are restricted, and routes are not appearing in the inet table, the use of 'bgp family inet labeled-unicast per-group-label' becomes necessary. This setting is crucial in environments where label distribution protocols like RSVP or LDP are not used. It enables the use of MPLS labels in BGP without relying on these protocols, which is essential for integrating L3VPN with EVPN over WAN links that do not support RSVP or LDP. The ''per-group-label'' option ensures that a single label is used for all routes exchanged with a BGP neighbor, which simplifies label management and conserves label space.

Reference:

Junos OS Routing Protocols Library for Routing Devices

JTI (Junos Telemetry Interface) native sensors are used to provide telemetry data with minimal latency. These sensors are embedded in the Junos OS and can provide real-time, granular device and interface statistics. JTI native sensors are preferred in scenarios requiring high-frequency data collection with the least amount of delay, making them ideal for monitoring in fast-paced environments like data center fabrics.

Reference:

Junos Telemetry Interface User Guide

In an EVPN-VXLAN environment, to ensure that multicast traffic is delivered only to leaf devices with interested receivers, IGMP snooping is required. IGMP snooping enables the leaf devices to listen to IGMP report and leave messages from hosts and make forwarding decisions based on this information. This way, multicast traffic is only forwarded to ports with interested multicast group members, optimizing bandwidth and resource utilization.

Reference:

EVPN-VXLAN Configuration Guide