Juniper JN0-683 Online Practice Questions and Exam Preparation

Juniper JN0-683 Online Questions & Answers

• Question 11:

  Exhibit.

  

  Referring to the exhibit, the spinel device has an underlay BGP group that is configured to peer with its neighbors' directly connected interfaces.

  Which two statements are true in this scenario? (Choose two.)

  A. The multihop statement is not required to establish the underlay BGP sessions.
  B. Load balancing for the underlay is not configured correctly.
  C. The multihop statement is required to establish the underlay BGP sessions.
  D. Load balancing for the underlay is configured correctly.
  A. The multihop statement is not required to establish the underlay BGP sessions.
  D. Load balancing for the underlay is configured correctly.

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  Explanation

  Understanding BGP Configuration in the Exhibit:

  The exhibit shows a BGP configuration on spine1 with a group named underlay, configured to peer with directly connected interfaces of other devices in the network.

  Multipath multiple-as:This statement allows the router to install multiple paths in the routing table for routes learned from different ASes, facilitating load balancing.

  Key Statements:

  A. The multihop statement is not required to establish the underlay BGP sessions:In this case, the BGP peers are directly connected (as indicated by their neighbor IP addresses), so the multihop statement is unnecessary. Multihop is

  typically used when BGP peers are not directly connected and packets need to traverse multiple hops.

  D. Load balancing for the underlay is configured correctly:The multipath { multiple-as; } statement in the configuration enables load balancing across multiple paths from different autonomous systems, which is appropriate for underlay

  networks in data center fabrics.

  Incorrect Statements:

  C. The multihop statement is required to establish the underlay BGP sessions:This is incorrect because the peers are directly connected, making the multihop statement unnecessary.

  B. Load balancing for the underlay is not configured correctly:This is incorrect because the configuration includes the necessary multipath settings for load balancing.

  Data Center

  References:

  BGP configurations in EVPN-VXLAN underlay networks are crucial for ensuring redundancy, load balancing, and efficient route propagation across the data center fabric.

• Question 12:

  Exhibit.

  

  You are troubleshooting an IP fabric (or your data center. You notice that your traffic is not being load balanced to your spine devices from your leaf devices. Referring to the configuration shown in the exhibit, what must be configured to solve this issue?

  A. The load-balance policy must be applied to the forwarding table under the routing-options hierarchy.
  B. The multipastmultiple -as configuration must be configured for each peer in the BGP spine group.
  C. The load-balance policy must be applied as an export policy to your BGP
  D. The load-balance policy must have a from statement that matches on protocol bgp.
  B. The multipastmultiple -as configuration must be configured for each peer in the BGP spine group.

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  Explanation

  IP Fabric Load Balancing:

  In the provided configuration, traffic is not being load-balanced to the spine devices. The issue likely relates to how BGP routes are being selected and whether Equal-Cost Multi-Path (ECMP) is functioning correctly.

  Multipath Multiple-AS:

  Option B:The multipath multiple-as configuration is essential when using BGP in an IP fabric where devices belong to different Autonomous Systems (AS). This setting allows BGP to consider multiple paths (even across different AS numbers)

  as equal cost, enabling ECMP and proper load balancing across spine devices.

  Conclusion:

  Option B:Correct--The multipath multiple-as configuration is necessary for achieving ECMP and effective load balancing in a multi-AS BGP environment.

• Question 13:

  Which three statements are correct about symmetric IRB routing with EVPN Type 2 routes? (Choose three.)

  A. An L3 interface (IRB) is required for each local VLAN.
  B. Symmetric routing requires MAC-VRF.
  C. Symmetric routing supports the EVPN service VLAN bundle.
  D. Symmetric routing requires an extra transit VNI for each VRF.
  E. Symmetric routing is less efficient than asymmetric routing.
  A. An L3 interface (IRB) is required for each local VLAN.
  B. Symmetric routing requires MAC-VRF.
  D. Symmetric routing requires an extra transit VNI for each VRF.

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  Explanation

  Symmetric IRB Routing with EVPN Type 2 Routes:

  Symmetric Routing: In symmetric IRB (Integrated Routing and Bridging), routing occurs in both directions at the ingress and egress leaf nodes using the same routing logic. This is contrasted with asymmetric routing, where different routing

  logic is used depending on the direction of the traffic.

  Required Components:

  Option A:An L3 IRB interface is necessary for each VLAN that participates in routing, as it handles the Layer 3 processing for the VLAN.

  Option B:MAC-VRF is required for symmetric routing to maintain a mapping of MAC addresses to the appropriate VRF, ensuring correct forwarding within the EVPN.

  Option D:A transit VNI (Virtual Network Identifier) is required for each VRF to encapsulate the Layer 3 traffic as it traverses the network, allowing the IP traffic to be appropriately forwarded.

  Conclusion:

  Option A:Correct--Each local VLAN needs an IRB interface for L3 processing.

  Option B:Correct--MAC-VRF is necessary for handling MAC address resolution in symmetric routing.

  Option D:Correct--Transit VNIs are required for routing VRF-specific traffic across the network.

  Options and are incorrect because: C E

  C:Symmetric routing can work with various VLAN models, including single or multiple VLANs within an EVPN instance.

  E:Symmetric routing is generally more efficient than asymmetric routing as it uses consistent routing logic in both directions.

• Question 14:

  Which three statements are correct about VXLAN control planes? (Choose three.)

  A. EVPN is inefficient and does not scale well.
  B. Both multicast and EVPN can facilitate MAC learning.
  C. Multicast is not agile and requires manual VNI mapping.
  D. EVPN enables fast convergence and updates.
  E. Multicast does not require as many resources.
  B. Both multicast and EVPN can facilitate MAC learning.
  D. EVPN enables fast convergence and updates.
  E. Multicast does not require as many resources.

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  Explanation

  VXLAN Control Planes:

  VXLAN (Virtual Extensible LAN) uses different control planes to handle MAC learning and traffic forwarding. The control planes include multicast and EVPN (Ethernet VPN).

  Multicast and EVPN Comparison:

  Option B:Both multicast and EVPN can be used for MAC learning in a VXLAN environment. Multicast is a more traditional approach, while EVPN is more advanced and supports distributed MAC learning.

  Option D:EVPN offers benefits such as fast convergence and rapid updates, making it more efficient and scalable for modern data center environments.

  Option E:Multicast does not require as many resources because it relies on traditional Layer 3 multicast mechanisms to distribute broadcast, unknown unicast, and multicast (BUM) traffic. However, it can be less flexible and less scalable

  compared to EVPN.

  Conclusion:

  Option B:Correct--Both control planes facilitate MAC learning.

  Option D:Correct--EVPN provides fast convergence and updates.

  Option E:Correct--Multicast is resource-efficient but less flexible.

• Question 15:

  Exhibit.

  

  Connections between hosts connected to Leaf-1 and Leaf-2 are not working correctly.

  Referring to the exhibit, which two configuration changes are required to solve the problem? (Choose two.)

  A. Configure the setswitch-options route-distinguisher 192.168.100.51:2 parameter on Leaf-1.
  B. Configure the set switch-options service-id 1 parameter on Leaf-2.
  C. Configure the setswitch-options vtep-source-interface100. 0 parameter on Leaf-1.
  D. Configure the set switch-options vrf-target target: 65000:55 parameter on Leaf-2.
  B. Configure the set switch-options service-id 1 parameter on Leaf-2.
  D. Configure the set switch-options vrf-target target: 65000:55 parameter on Leaf-2.

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  Explanation

  Review of the Exhibit:

  The exhibit shows the switch configuration for Leaf-1 and Leaf-2. The configurations include route distinguishers, VRF targets, and service IDs, all of which are crucial for ensuring proper operation in an EVPN-VXLAN environment.

  Service-ID Consistency:

  The service ID must be consistent across all participating leaf devices in the same EVPN instance to ensure that they are part of the same VXLAN overlay network.

  VRF Target Consistency:

  The vrf-target parameter must also be consistent across devices to ensure that VRFs (Virtual Routing and Forwarding instances) are correctly imported and exported between leaf nodes.

  Conclusion:

  Option B:Correct--Setting the same service-id on Leaf-2 ensures that it is part of the same VXLAN overlay as Leaf-1. Option D:Correct--The vrf-target on Leaf-2 should match Leaf-1 to ensure consistent routing policies and proper route exchange.

• Question 16:

  You are asked to identify microburst traffic occurring in the network leading lo packet drops in your data center switches Which two tools would be used in this scenario? (Choose two.)

  A. port mirroring
  B. Traceoptions
  C. port buffer monitoring
  D. syslog
  A. port mirroring
  C. port buffer monitoring

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  Explanation

  Identifying Microburst Traffic:

  Microbursts are short spikes in network traffic that can overwhelm buffers and cause packet drops. Detecting and analyzing microbursts is crucial for understanding where packet loss might be occurring in a data center network.

  Port Buffer Monitoring:

  Port Buffer Monitoring:This tool specifically tracks the usage of switch buffers, helping to identify when microbursts are causing buffers to overflow, leading to packet drops.

  Port Mirroring:

  Port Mirroring:This tool allows you to monitor real-time traffic on a specific port by copying the traffic to another port where it can be analyzed, often with a packet analyzer. While port mirroring doesn't directly detect microbursts, it helps

  capture traffic patterns that can indicate microbursts.

  Conclusion:

  Option C:Correct--Port buffer monitoring directly identifies buffer overflows caused by microbursts.

  Option A:Correct--Port mirroring allows for the detailed capture and analysis of traffic patterns, which can reveal microburst behavior.

  Options B(Traceoptions) and (Syslog) are less effective in identifying microburst traffic. Traceoptions focus D on control plane traffic debugging, and Syslog is more about logging system events than detecting high- frequency traffic spikes.

• Question 17:

  You are asked to deploy 100 QFX Series devices using ZTP Each OFX5120 requires a different configuration. In this scenario, what are two components that you would configure on the DHCP server? (Choose two.)

  A. the IP address of the FTP server
  B. the MAC address for each OFX5120
  C. the MAC address of the FTP server
  D. the management IP address for each OFX5120
  B. the MAC address for each OFX5120
  D. the management IP address for each OFX5120

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  Explanation

  Zero Touch Provisioning (ZTP):

  ZTP allows for the automated configuration of network devices, like QFX Series switches, without manual intervention. During ZTP, a switch will obtain its configuration from a DHCP server and then download the required software and

  configuration files from a specified server (e.

  g., FTP, HTTP).

  DHCP Server Configuration:

  Option B:The DHCP server needs to know the MAC address for each QFX5120 to provide a specific configuration based on the device identity. By mapping the MAC address to a particular configuration, the DHCP server can ensure that

  each switch gets the correct configuration.

  Option D:The management IP address for each QFX5120 must also be assigned by the DHCP server. This IP address allows the device to communicate on the network and access the configuration files and other required resources during

  the ZTP process.

  Conclusion:

  Option B:Correct--MAC addresses allow the DHCP server to identify each QFX5120 and assign the appropriate configuration.

  Option D:Correct--Management IP addresses are essential for network communication during ZTP.

• Question 18:

  Whatare two supported methods (or exporting data when using the Junos telemetry interface? (Choose two.)

  A. using REST
  B. using UDP
  C. using SNMP
  D. using gRPC
  B. using UDP
  D. using gRPC

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  Explanation

  Junos Telemetry Interface (JTI):

  The Junos Telemetry Interface is a framework that allows network operators to collect real-time telemetry data from Juniper devices. This data can be used for monitoring, analytics, and network automation.

  Data Export Methods:

  Option B:UDP (User Datagram Protocol)is a lightweight, connectionless protocol used for exporting telemetry data quickly with minimal overhead. While it doesn't guarantee delivery, it is suitable for high-speed data transfer where occasional

  packet loss is acceptable.

  Option D:gRPC (gRPC Remote Procedure Call)is a modern, high-performance method for data export that supports streaming and remote procedure calls, making it ideal for more complex telemetry data use cases.

  Conclusion:

  Option B:Correct--UDP is supported for exporting telemetry data.

  Option D:Correct--gRPC is also supported, offering advanced streaming capabilities

• Question 19:

  You are deploying a Clos IP fabric with an oversubscription ratio of 3:1. In this scenario, which two statements are correct? (Choose two.)

  A. The oversubscription ratio remains the same when you remove spine devices.
  B. The oversubscription ratio decreases when you add spine devices.
  C. The oversubscription ratio increases when you remove spine devices.
  D. The oversubscription ratio remains the same when you add spine devices.
  B. The oversubscription ratio decreases when you add spine devices.
  C. The oversubscription ratio increases when you remove spine devices.

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  Explanation

  Understanding Oversubscription in a Clos Fabric:

  The oversubscription ratio in a Clos IP fabric measures the ratio of the amount of edge (leaf) bandwidth to the core (spine) bandwidth. An oversubscription ratio of 3:1 means that there is three times more edge bandwidth compared to core

  bandwidth.

  Impact of Adding/Removing Spine Devices:

  Option C:If you remove spine devices , the total available core bandwidth decreases, while the edge bandwidth remains the same. This results in anincrease in the oversubscription ratio because there is now less core bandwidth to handle the

  same amount of edge traffic.

  Option B:Conversely, if you add spine devices , the total core bandwidth increases. This decreases the oversubscription ratio because more core bandwidth is available to handle the edge traffic.

  Conclusion:

  Option C:Correct--Removing spine devices increases the oversubscription ratio.

  Option B:Correct--Adding spine devices decreases the oversubscription ratio.

• Question 20:

  Exhibit.

  

  Both DC and DC2 ate using EVPN-VXLAN technology deployed using an ERB architecture. A server on the Red VLAN must communicate with a server on the Green VLAN. The Blue VLAN in DC and DC2 needs to be the same VLAN.

  Which statement is correct in this scenario?

  A. The eight spine devices must be configured as border spine devices; a full mush interconnect must exist between all eight spine devices and the Blue VLAN must be stitched together
  B. An interconnect is required between the four SRX Series devices; the Blue VLAN must be stretched and a transit VNI must be added for the Red and Green VLANs.
  C. An interconnect is required between four leaf devices in the services blocks; the Red VLAN and the Green VLAN must be stitched and the Blue VLAN must be stretched.
  D. A lean super spine device must be added to DC and DC2; all VLANs must be stretched to the lean super spine device and the lean super spine devices must stitch all the VLANs together.
  B. An interconnect is required between the four SRX Series devices; the Blue VLAN must be stretched and a transit VNI must be added for the Red and Green VLANs.

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  Explanation

  ERB Architecture in EVPN-VXLAN:

  ERB (Edge Routed Bridging) architecture is commonly used in data center networks where routing decisions are made at the network edge (leaf or border devices), while bridging (Layer 2 forwarding) is extended across the fabric. This

  architecture allows for efficient L3 routing while still enabling L2 services like VLANs to span across multiple locations.

  VLAN and VNI Configuration:

  The scenario specifies that a server on the Red VLAN needs to communicate with a server on the Green VLAN. Since these VLANs are in different data centers (DC and DC2), and given the use of EVPN-VXLAN, the communication between

  these VLANs will require a transit VNI (Virtual Network Identifier). This transit VNI will allow traffic to traverse the VXLAN tunnel across the DCI (Data Center Interconnect).

  Interconnect between SRX Series Devices:

  The exhibit shows SRX Series Chassis Clusters used as service devices (likely for firewalling or other security services). These devices need to be interconnected between the two data centers to ensure that VLANs can communicate

  effectively. The Blue VLAN needs to be stretched between DC and DC2 to maintain the same Layer 2 domain across both data centers.

  Conclusion:

  Option B:Correct--Interconnecting the SRX Series devices will ensure the necessary service chaining, while stretching the Blue VLAN and adding a transit VNI for the Red and Green VLANs will enable the required communication across the

  data centers.