Juniper JN0-683 Online Practice Questions and Exam Preparation

Juniper JN0-683 Online Questions & Answers

• Question 1:

  You are asked to interconnect two of your company's data centers across the IP backbone. Both data centers have their own unique IP space and do not require any bridging. In this scenario, which two actions would accomplish this task? (Choose two.)

  A. Configure a Type 2 EVPN route for each unique prefix.
  B. Configure peering for EVPN between border leaf nodes in each data center.
  C. Configure a Type 5 EVPN route for each unique prefix.
  D. Configure peering for EVPN between all leaf nodes within each data center.
  B. Configure peering for EVPN between border leaf nodes in each data center.
  C. Configure a Type 5 EVPN route for each unique prefix.

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  Explanation

  Interconnecting Data Centers:

  The scenario requires interconnecting two data centers with unique IP spaces across an IP backbone. The key point is that bridging is not required, so Layer 3 routing methods must be used.

  EVPN Configuration:

  Option B:Establishing EVPN peering between the border leaf nodes in each data center is the most appropriate solution as it allows for exchanging routing information between the two data centers. This ensures that the routes are properly

  distributed without the need for L2 bridging.

  Option C:Configuring Type 5 EVPN routes is necessary for advertising IP prefixes (Layer 3 routes) across the EVPN. Type 5 routes allow for the exchange of IP prefixes between the two data centers, enabling the necessary routing

  functionality without the need for bridging.

  Conclusion:

  Option B:Correct--Peering between border leaf nodes sets up the necessary route exchange between data centers.

  Option C:Correct--Type 5 EVPN routes are essential for exchanging Layer 3 prefixes between data centers.

• Question 2:

  Exhibit.

  

  The exhibit shows the truncated output of the show evpn database command.

  Given this output, which two statements are correct about the host with MAC address 40:00:dc:01:00:04? (Choose two.)

  A. The host is assigned IP address 10.4.4.5.
  B. The host is originating from irb.300.
  C. The host is located on VN110002.
  D. The host is originating from an ESI LAG.
  A. The host is assigned IP address 10.4.4.5.
  D. The host is originating from an ESI LAG.

  ---

  Explanation

  Understanding the Output:

  The show evpn database command output shows the MAC address, VLAN, active source, timestamp, and IP address associated with various hosts in the EVPN instance.

  Analysis of the MAC Address:

  Option A:The MAC address 40:00:dc:01:00:04 is associated with the IP address 10.4.4.5, as indicated by the output in the IP address column. This confirms that this host has been assigned the IP 10.4.4.5. Option D:The active source for the MAC address 40:00:dc:01:00:04 is listed as 00:02:00:00:00:

  04:00:04:00:00:04:00:04, which indicates that the host is connected via an ESI (Ethernet Segment Identifier) LAG (Link Aggregation Group). This setup is typicallyused in multi-homing scenarios to provide redundancy and load balancing

  across multiple physical links.

  Conclusion:

  Option A:Correct--The host with MAC 40:00:dc:01:00:04 is assigned IP 10.4.4.5. Option D:Correct--The host is originating from an ESI LAG, as indicated by the active source value.

• Question 3:

  You are asked to interconnect Iwo data centers using a method that provides EVPN Type 2 connectivity, is highly scalable, and limits VXLAN tunnels between border leafdevices. What will satisfy these requirements?

  A. over the top full-mesh interconnect
  B. EVPN Type 2 stretch
  C. IP VPN
  D. Type 2 seamless stitching
  D. Type 2 seamless stitching

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  Explanation

  Requirement Analysis:

  The scenario requires a solution to interconnect two data centers that supports EVPN Type 2 connectivity. The solution must be highly scalable and must minimize the number of VXLAN tunnels between border leaf devices.

  Understanding Type 2 Seamless Stitching:

  Option D:Type 2 seamless stitchingis a method used in EVPN to provide Layer 2 connectivity (such as MAC address mobility) across different VXLAN segments. It is scalable because it allows only necessary tunnels to be established

  between border leaf devices, reducing the overhead of maintaining a full mesh of VXLAN tunnels.

  Conclusion:

  Option D:Correct--Type 2 seamless stitching satisfies the requirement by enabling scalable, efficient interconnection of two data centers with minimal VXLAN tunnels.

• Question 4:

  You are implementing seamless stitching between two data centers and have a proposedconfiguration for a border leafdevice.

  In this scenario, which two statements are correct? {Choose two.)

  A. The translation-vni must match in both data centers.
  B. The translation-vni must be different in each data center.
  C. The ESI must be different in each data center.
  D. The ESI must match in both data centers.
  B. The translation-vni must be different in each data center.
  D. The ESI must match in both data centers.

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  Explanation

  Understanding Seamless Stitching:

  Seamless stitching is used in EVPN to interconnect two data centers, allowing for consistent Layer 2 and Layer 3 connectivity across them. This is often achieved by translating VNIs (Virtual Network Identifiers) between the data centers.

  Translation-VNI:

  Option B:The translation VNI must be different in each data center to ensure that traffic can be correctly routed and distinguished as it crosses between the data centers. This differentiation helps to maintain the integrity of the traffic flows and

  prevents any potential overlap or conflict in VNIs.

  Ethernet Segment Identifier (ESI):

  Option D:The ESI must match in both data centers to ensure that the same Ethernet segment (which could be multihomed) is recognized consistently across the data centers. Matching ESIs are crucial for maintaining a unified view of the

  Ethernet segment across the interconnected fabric.

  Conclusion:

  Option B:Correct--Translation VNIs must be unique to each data center for proper traffic distinction.

  Option D:Correct--Matching ESIs are necessary to maintain consistent Ethernet segment identification across both data centers.

• Question 5:

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

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

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  Explanation

  Understanding Oversubscription Ratio in IP Fabrics:

  The oversubscription ratio in an IP fabric typically refers to the ratio of the available bandwidth at the edge of the network (leaves) to the available bandwidth at the core or spine. A 3:1 oversubscription ratio means that for every 3 units of

  bandwidth at the leaves, there is 1 unit of bandwidth at the spine.

  Impact of Adding or Removing Leaf Devices:

  Removing Leaf Devices:When you remove leaf devices, the amount of total edge bandwidth decreases while the bandwidth in the spine remains constant. This causes the oversubscription ratio to increase because there is now less total

  bandwidth to distribute across the same amount of spine bandwidth.

  Adding Leaf Devices:Conversely, when you add leaf devices, the total edge bandwidth increases. Since the spine bandwidth remains the same, the oversubscription ratio would remain the same if the additional leaves consume their share of

  the available bandwidth proportionally.

  Conclusion:

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

  Option D:Correct--Adding leaf devices typically maintains the oversubscription ratio assuming uniform bandwidth distribution.

• Question 6:

  Exhibit.

  

  Referring tothe exhibit, which statement is correct?

  A. VNI 100 is not configured on the remote VTEP.
  B. The MAC address is unknown and not in the forwarding table of the remote VTEP.
  C. The remote VTEP is not responding.
  D. The MAC address is known but not reachable by the remote VTEP
  B. The MAC address is unknown and not in the forwarding table of the remote VTEP.

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  Explanation

  Analyzing the Exhibit Output:

  The command ping overlay tunnel-type vxlan is used to test the VXLAN tunnel between two VTEPs (VXLAN Tunnel Endpoints). The output shows a warning about missing hash parameters, but more importantly, it displays the result: End-

  System Not Present.

  Understanding the Response:

  The message End-System Not Present indicates that the remote VTEP (192.168.2.20) did not find the MAC address 00:00:5E:00:53:CC in its forwarding table. This typically means that the MAC address is unknown to the remote VTEP, and

  as a result, it could not forward the packet to the intended destination.

  Conclusion:

  Option B:Correct--The MAC address is unknown and is not in the forwarding table of the remote VTEP, which is why the system reports that the "End-System" is not present.

• Question 7:

  You want to convert an MX Series router from a VXLAN Layer 2 gateway to a VXLAN Layer 3 gateway for VNI 100. You have already configured an IRB interface. In this scenario, which command would you use to accomplish this task?

  A. set protocols isis interface irb.100 passive
  B. set vlans VLAN-100 13-interface irb.100
  C. set bridge-domains VLAN-100 routing-interface irb.100
  D. set protocols ospf area 0.0.0.0 interface irb.100 passive
  C. set bridge-domains VLAN-100 routing-interface irb.100

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  Explanation

  Scenario Overview:

  Converting an MX Series router from a VXLAN Layer 2 gateway to a VXLAN Layer 3 gateway involves transitioning the router's functionality from simply bridging traffic within a VXLAN segment to routing traffic between different segments.

  Key Configuration Requirement:

  IRB (Integrated Routing and Bridging) Interface:An IRB interface allows for both Layer 2 switching and Layer 3 routing. To enable routing for a specific VNI (VXLAN Network Identifier), the IRB interface must be associated with the routing

  function in the corresponding bridge domain.

  Correct Command:

  C. set bridge-domains VLAN-100 routing-interface irb.100:This command correctly binds the IRB interface to the bridge domain, enabling Layer 3 routing functionality within the VXLAN for VNI 100. This effectively transitions the device from

  operating solely as a Layer 2 gateway to a Layer 3 gateway.

  Data Center

  References:

  This configuration step is essential when converting a Layer 2 VXLAN gateway to a Layer 3 gateway, enabling the MX Series router to route between VXLAN segments.

• Question 8:

  You are implementing VXLAN broadcast domains in your data center environment. Which two statements are correct in this scenario? (Choose two.)

  A. A VXLAN packet does not contain a VLAN ID.
  B. The VNI must match the VLAN tag to ensure that the remote VTEP can decapsulate VXLAN packets.
  C. Layer 2 frames are encapsulated by the source VTEP.
  D. The VNI is a 16-bit value and can range from 0 through 16.777.215.
  A. A VXLAN packet does not contain a VLAN ID.
  C. Layer 2 frames are encapsulated by the source VTEP.

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  Explanation

  VXLAN Overview:

  VXLAN (Virtual Extensible LAN) is a network virtualization technology that encapsulates Layer 2 Ethernet frames into Layer 3 UDP packets for transmission over an IP network. It allows the creation of Layer 2 overlay networks across a Layer

  3 infrastructure.

  Understanding VXLAN Components:

  VTEP (VXLAN Tunnel Endpoint):A VTEP is responsible for encapsulating and decapsulating Ethernet frames into and from VXLAN packets.

  VNI (VXLAN Network Identifier):A 24-bit identifier used to distinguish different VXLAN segments, allowing for up to 16 million unique segments.

  Correct Statements:

  C. Layer 2 frames are encapsulated by the source VTEP:This is correct. In a VXLAN deployment, the source VTEP encapsulates the original Layer 2 Ethernet frame into a VXLAN packet before transmitting it over the IP network to the

  destination VTEP, which then decapsulates it.

  A. A VXLAN packet does not contain a VLAN ID:This is correct. The VXLAN header does not carry the original VLAN ID; instead, it uses the VNI to identify the network segment. The VLAN ID is local to the switch and does not traverse the

  VXLAN tunnel.

  Incorrect Statements:

  B. The VNI must match the VLAN tag to ensure that the remote VTEP can decapsulate VXLAN packets:This is incorrect. The VNI is independent of the VLAN tag, and the VLAN ID does not need to match the VNI. The VNI is what the remote

  VTEP uses to identify the correct VXLAN segment.

  D. The VNI is a 16-bit value and can range from 0 through 16,777,215:This is incorrect because the VNI is a 24-bit value, allowing for a range of 0 to 16,777,215. Data Center

  References:

  VXLAN technology is critical for modern data centers as it enables scalability and efficient segmentation without the constraints of traditional VLAN limits.

• Question 9:

  Exhibit.

  

  Given the configuration shown in the exhibit, why has the next hop remained the same for the EVPN routes advertised to the peer 203.0.113.2?

  A. EVPN routes cannot have the next hop changed.
  B. The export policy is incorrectly configured.
  C. The vrf-export parameter must be applied.
  D. The vpn-apply-export parameter must be applied to this peer.
  D. The vpn-apply-export parameter must be applied to this peer.

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  Explanation

  Understanding the Configuration:

  The configuration shown in the exhibit involves an EVPN (Ethernet VPN) setup using BGP as the routing protocol. The export policy named CHANGE_NH is applied to the BGP group evpn- peer, which includes a rule to change the next hop

  for routes that match the policy.

  Issue with Next Hop Not Changing:

  The policy CHANGE_NH is correctly configured to change the next hop to 203.0.113.10 for the matching routes. However, the next hop remains unchanged when advertising EVPN routes to the peer 203.0.113.2. Reason for the Issue:

  In Junos OS, when exporting routes for VPNs (including EVPN), the next-hop change defined in a policy will not take effect unless the vpn-apply-export parameter is used inthe BGP configuration. This parameter ensures that the export policy

  is applied specifically to VPN routes.

  The vpn-apply-export parameter must be included to apply the next-hop change to EVPN routes.

  Correct Answer Explanation:

  D. The vpn-apply-export parameter must be applied to this peer:This is the correct solution because the next hop in EVPN routes won't be altered without this parameter in the BGP configuration. It instructs the BGP process to apply the

  export policy to the EVPN routes.

  Data Center

  References:

  This behavior is standard in EVPN deployments with Juniper Networks devices, where the export policies applied to VPN routes require explicit invocation using vpn-apply-export to take effect.

• Question 10:

  You are asked to automatically provision new Juniper Networks devices in your network with minimal manual intervention Before you begin, which two statements are correct? (Choose two.)

  A. You must have a DHCP server that provides the location of the software image and configuration files.
  B. You must have a system log (syslog) server to manage system log messages and alerts.
  C. You must have an NTP server to perform time synchronization.
  D. You must have a file server that stores software image and configuration files.
  A. You must have a DHCP server that provides the location of the software image and configuration files.
  D. You must have a file server that stores software image and configuration files.

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  Explanation

  Zero-Touch Provisioning (ZTP):

  ZTP is a feature that allows for the automatic provisioning of devices with minimal manual intervention. It is widely used in large-scale deployments to quickly bring new devices online.

  Key Requirements for ZTP:

  A. DHCP Server:A DHCP server is crucial for ZTP as it provides the necessary information to new devices, such as the IP address, the location of the software image, and configuration files.

  D. File Server:The file server is where the software image and configuration files are stored. The device downloads these files during the provisioning process.

  Incorrect Options:

  B. Syslog Server:While a syslog server is important for logging and monitoring, it is not a requirement for the initial provisioning process.

  C. NTP Server:An NTP server is used for time synchronization, which is essential for accurate logging and operation but not specifically required for ZTP.

  Data Center

  References:

  ZTP simplifies the deployment process by automating the initial configuration steps, relying heavily on DHCP for communication and a file server for delivering the necessary configuration and software.