Juniper JN0-683 Online Practice Questions and Exam Preparation

Juniper JN0-683 Online Questions & Answers

• Question 1:

  You are selling up an EVPN-VXLAN architecture (or your new data center. thisinitial deployment will be less than 50 switches: however, it could scale up to 250 switches over time supporting 1024 VLANs. You are still deciding whether to use symmetric or asymmetric routing.

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

  A. Symmetric routing needs an extra VLAN with an IRB interface for each L3 VRF instance.
  B. Asymmetric routing is easier lo monitor because of the transit VNI.
  C. Symmetric routing supports higher scaling numbers.
  D. Asymmetric routing routes traffic on the egress switch.
  C. Symmetric routing supports higher scaling numbers.
  D. Asymmetric routing routes traffic on the egress switch.

  ---

  explanation:

  Explanation

  Symmetric vs. Asymmetric Routing in EVPN-VXLAN:

  Symmetric Routing:Traffic enters and exits the VXLAN network through the same VTEP, regardless of the source or destination. This approach simplifies routing decisions, especially in large networks, and is generally more scalable.

  Asymmetric Routing:The routing occurs on the egress VTEP. This method can be simpler to deploy in smaller environments but becomes complex as the network scales, particularly with larger numbers of VNIs and VLANs.

  Correct Statements:

  C. Symmetric routing supports higher scaling numbers:Symmetric routing is preferred in larger EVPN-VXLAN deployments because it centralizes routing decisions, which can be more easily managed and scaled.

  D. Asymmetric routing routes traffic on the egress switch:This is accurate, as asymmetric routing means the routing decision is made at the final hop, i.e., the egress VTEP before the traffic reaches its destination.

  Incorrect Statements:

  A. Symmetric routing needs an extra VLAN with an IRB interface for each L3 VRF instance:This is not accurate. Symmetric routing does not require an extra VLAN per VRF; rather, it uses the same VLAN/VNI across the network, simplifying

  routing and VLAN management.

  B. Asymmetric routing is easier to monitor because of the transit VNI:Asymmetric routing is not necessarily easier to monitor; in fact, it can add complexity due to the split routing logic between ingress and egress points.

  Data Center

  References:

  The choice between symmetric and asymmetric routing in an EVPN-VXLAN environment depends on network size, complexity, and specific operational requirements. Symmetric routing is generally more scalable and easier to manage in

  large-scale deployments.

• Question 2:

  You want to ensure thatVXLAN traffic from the xe-0/0/12 interlace is being encapsulatedby logical vlep. 32770 and sent to a remote leaf device in this scenario, which command would you use to verify that traffic is flowing?

  A. monitor traffic interface xe-0/0/12
  B. show interface terse vtep.32770
  C. show interfaces terse vtep.32770 statistics
  D. show interfaces vtep.32770 detail
  C. show interfaces terse vtep.32770 statistics

  ---

  explanation:

  Explanation

  VXLAN Traffic Verification:

  To ensure VXLAN traffic from the xe-0/0/12 interface is correctly encapsulated by the logical vtep.32770 and sent to a remote leaf device, it is essential to monitor the relevant interface statistics.

  The command show interfaces terse vtep.32770 statistics provides a concise overview of the traffic statistics for the specific VTEP interface, which can help verify whether traffic is being correctly encapsulated and transmitted.

  This command is particularly useful for quickly checking the traffic counters and identifying any potential issues with VXLAN encapsulation or transmission.

  It allows you to confirm that traffic is flowing as expected, by checking the transmitted and received packet counters.

  Data Center

  References:

  Monitoring interface statistics is a crucial step in troubleshooting and validating network traffic, particularly in complex overlay environments like EVPN-VXLAN.

• Question 3:

  You manage an IP fabric with an EVPN-VXLAN overlay. You have multiple tenants separated using multiple unique VRF instances. You want to determine the routing information that belongs in each routing instance's routing table.

  In this scenario, which property is used for this purpose?

  A. the VRF target community
  B. the routing instance type
  C. the VRF table label
  D. the route distinguisher value
  D. the route distinguisher value

  ---

  explanation:

  Explanation

  Understanding VRF and Routing Instances:

  In an EVPN-VXLAN overlay network, multiple tenants are separated using unique VRF (Virtual Routing and Forwarding) instances. Each VRF instance maintains its own routing table, allowing for isolated routing domains within the same

  network infrastructure.

  Role of Route Distinguisher:

  Route Distinguisher (RD):The RD is a unique identifier used in MPLS and EVPN environments to distinguish routes belonging to different VRFs. The RD is prepended to the IP address in the route advertisement, ensuring that routes from

  different tenants remain unique even if they use the same IP address range.

  Correct Property:

  D. the route distinguisher value:This is the correct answer because the RD is crucial in determining which routing information belongs to which VRF instance. It ensures that each VRF' s routing table only contains relevant routes, maintaining

  isolation between tenants.

  Data Center

  References:

  The RD is a key element in MPLS and EVPN-based multi-tenant environments, ensuring proper routing segregation and isolation for different VRFs within the data center fabric.

• Question 4:

  As part of the onboarding process for new switches being added to your data centers, your company uses Juniper Networks' ZTP process. As part of the ZTP process, a script is executed by the devices being onboarded.

  Which statement is correct in this scenario?

  A. The Junos ZTP process supports Shell. JScript. and Ansible.
  B. The Junos ZTP process supports Python, SLAX, and Perl.
  C. The Junos ZTP process supports JScript. Ansible. and Perl.
  D. The Junos ZTP process supports Shell. Python, and SLAX.
  D. The Junos ZTP process supports Shell. Python, and SLAX.

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  explanation:

  Explanation

  Zero Touch Provisioning (ZTP):

  Juniper Networks' ZTP (Zero Touch Provisioning) process automates the deployment of new devices by allowing them to fetch and execute scripts for configuration and setup as they are powered on and connected to the network.

  Supported Scripting Languages:

  The Junos OS supports several scripting languages that can be used during the ZTP process:

  Shellscripts are often used for general automation tasks.

  Pythonis a widely supported language in Junos, offering powerful scripting capabilities for automating network tasks.

  SLAX(Service Logic Execution Environment) is a scripting language specific to Junos, designed to automate configuration tasks and simplify network operations.

  Conclusion:

  Option D:Correct--Junos ZTP supports Shell, Python, and SLAX, making it the correct choice among the provided options.

• Question 5:

  Which parameter is used to associate a received route with a local VPN route table?

  A. route-target community
  B. VLAN ID
  C. VNI
  D. route-distinguisher
  A. route-target community

  ---

  explanation:

  Explanation

  Understanding VPN Route Table Association:

  In MPLS/VPN and EVPN networks, the route-target community is a BGP extended community attribute used to control the import and export of VPN routes. It associates received routes with the appropriate VPN route tables on the PE

  (Provider Edge) routers.

  Function of Route-Target Community:

  The route-target community tag ensures that routes are imported into the correct VRF (Virtual Routing and Forwarding) instance, allowing them to be correctly routed within the VPN.

  Conclusion:

  Option A:Correct--The route-target community is used to associate received routes with a local VPN route table.

• Question 6:

  Which two statements are true about EVPN routes for Data Center Interconnect? (Choose two.)

  A. Type 5 EVPN routes require a VXLAN tunnel to the protocol next hop.
  B. Type 2 EVPN routes do not require a VXLAN tunnel to the protocol next hop.
  C. Type 2 EVPN routes require a VXLAN tunnel to the protocol next hop.
  D. Type 5 EVPN routes do not require a VXLAN tunnel to the protocol next hop.
  B. Type 2 EVPN routes do not require a VXLAN tunnel to the protocol next hop.
  D. Type 5 EVPN routes do not require a VXLAN tunnel to the protocol next hop.

  ---

  explanation:

  Explanation

  Type 2 EVPN Routes:

  Type 2 routesadvertise MAC addresses within an EVPN instance and are used primarily for Layer 2 bridging. These routes do not require a VXLAN tunnel to the protocol next hop because they operate within the same Layer 2 domain.

  Type 5 EVPN Routes:

  Type 5 routesare used to advertise IP prefixes (Layer 3 routes) within EVPN. Similar to Type 2 routes, they do not require a VXLAN tunnel to the protocol next hop because they represent L3 routes, which are managed at the routing layer

  without the need for VXLAN encapsulation.

  Conclusion:

  Option B:Correct--Type 2 routes do not need a VXLAN tunnel to the next hop, as they are used for Layer 2. Option D:Correct--Type 5 routes also do not need a VXLAN tunnel because they operate at Layer 3, handling IP prefixes.

• 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:

  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:

  Which two statements are true about IP fabrics using unnumbered BGP? (Choose two.)

  A. Unnumbered BGP requires that family inet6is configured on each interface.
  B. Unnumbered BGP peering automatically provisions IPv6 peering.
  C. Unnumbered BGP requires that family inet is configured on each interface.
  D. Unnumbered BGP peering automatically provisions IPv4 peering.
  C. Unnumbered BGP requires that family inet is configured on each interface.
  D. Unnumbered BGP peering automatically provisions IPv4 peering.

  ---

  explanation:

  Explanation

  Understanding Unnumbered BGP:

  Unnumbered BGP (Border Gateway Protocol) allows BGP peering between routers without assigning specific IP addresses to the interfaces. Instead, it uses the loopback address or another router identifier for the BGP session, making IP

  address management more straightforward in large-scale networks.

  Family inet Configuration:

  Option C:The family inet configuration is required on each interface involved in unnumbered BGP peering to support IPv4 address families. This ensures that IPv4 peering sessions can be established between devices.

  Automatic IPv4 Peering:

  Option D:Unnumbered BGP peering automatically provisions IPv4 peering sessions. This simplifies the configuration by eliminating the need to manually assign and manage IP addresses for BGP peering.

  Conclusion:

  Option C:Correct--Unnumbered BGP requires the family inet configuration for IPv4. Option D:Correct--Unnumbered BGP automatically provisions IPv4 peering, simplifying setup.

• Question 9:

  Exhibit.

  

  A VXLAN tunnel has been created between leaf1and Ieaf2 in your data center. Referring to the exhibit, which statement is correct?

  A. Traffic sent from server1to server2 will be dropped on Ieaf2.
  B. Traffic sent from server1to server2 will be tagged with VLAN ID 100 on Ieaf2 and forwarded to server2.
  C. Traffic sent from server1to server2 will be tagged with VLAN ID 200 on Ieaf2 and forwarded to server2.
  D. Traffic sent from server1to server2 will be dropped on leaf1.
  C. Traffic sent from server1to server2 will be tagged with VLAN ID 200 on Ieaf2 and forwarded to server2.

  ---

  explanation:

  Explanation

  Understanding VXLAN Tunneling:

  VXLAN (Virtual Extensible LAN) is a network virtualization technology that addresses the scalability issues associated with traditional VLANs. VXLAN encapsulates Ethernet frames in UDP, allowing Layer 2 connectivity to extend across Layer

  3 networks.

  Each VXLAN network is identified by a unique VXLAN Network Identifier (VNI). In this exhibit, we have two VNIs, 5100 and 5200, assigned to the VXLAN tunnels between leaf1 and leaf2. Network Setup Details:

  Leaf1:Connected to Server1 with VLAN ID 100 and associated with VNI 5100.

  Leaf2:Connected to Server2 with VLAN ID 200 and associated with VNI 5200.

  Spine:Acts as the interconnect between leaf switches.

  Traffic Flow Analysis:

  When traffic is sent from Server1 to Server2, it is initially tagged with VLAN ID 100 on leaf1. The traffic is encapsulated into a VXLAN packet with VNI 5100 on leaf1. The packet is then sent across the network (via the spine) to leaf2. On leaf2, the VXLAN header is removed, and the original Ethernet frame is decapsulated.

  Leaf2 will then associate this traffic with VLAN ID 200 before forwarding it to Server2. Correct Interpretation of the Exhibit:

  The traffic originating from Server1, which is tagged with VLAN ID 100, will be encapsulated into VXLAN and transmitted to leaf2. Upon arrival at leaf2, it will be decapsulated, and since it is associated with VNI 5200 on leaf2, the traffic will be retagged with VLAN ID 200.

  Therefore, the traffic will reach Server2 tagged with VLAN ID 200, which matches the network configuration shown in the exhibit.

  Data Center

  References:

  This configuration is typical in data centers using VXLAN for network virtualization. It allows isolated Layer 2 segments (VLANs) to be stretched across Layer 3 boundaries while maintaining distinct VLAN IDs at each site.

  This approach is efficient for scaling large data center networks while avoiding VLAN ID exhaustion and enabling easier segmentation.

  In summary, the correct behavior, as per the exhibit and the detailed explanation, is that traffic sent from Server1 will be tagged with VLAN ID 200 when it reaches Server2 via leaf2. This ensures proper traffic segmentation and handling

  across the VXLAN-enabled data center network.

• Question 10:

  Exhibit.

  

  Host A is connected to vlan 100 on lead. Host B is connected to vlan 200 on leaf1. Host A and Host B ate unable to communicate. You have reviewed the touting and your hosts have the correct default route (.1)

  Referring to the exhibit, which two commands will solve the problem? (Choose two.)

  A. delete vlans vn200 13-interface irb.200
  B. set interfaces irb unit 100 family inet address 192-168.100.1
  C. set routing-options static route 0.0.0.0/0 next-hop 192.168.200.10
  D. set vlans vn10013-interface irb.100
  C. set routing-options static route 0.0.0.0/0 next-hop 192.168.200.10
  D. set vlans vn10013-interface irb.100

  ---

  explanation:

  Explanation

  In the provided network configuration, Host A is in VLAN 100 and Host B is in VLAN 200. The issue arises because these two hosts are unable to communicate, which indicates that either the interfaces are not properly linked to their

  respective VLANs, or there is a missing static route required for inter-VLAN routing.

  Step-by-Step Analysis:

  VLAN Assignment:

  The exhibit shows that irb.200 is correctly associated with VLAN 200 in the configuration. However, there is no corresponding irb.100 for VLAN 100. Without irb.100, the network lacks the logical interface to handle routing for VLAN 100. Thus,

  adding irb.100 to VLAN 100 is necessary.

  Command to solve this:

  set vlans vn100 13-interface irb.100

  Static Route Configuration:

  For inter-VLAN routing to occur, a static route needs to be configured that allows traffic to pass between different subnets (in this case, between VLAN 100 and VLAN 200). The command set routing-options static route 0.0.0.0/0 next-hop

  192.168.200.10 would add a static route that directs all traffic from VLAN 100 to the correct gateway (192.168.200.10), which is necessary to route traffic between the two VLANs.

  Command to solve this:

  set routing-options static route 0.0.0.0/0 next-hop 192.168.200.10

  Explanation of Incorrect Options:

  Option A (delete vlans vn200 13-interface irb.200): This would remove the logical interface associated with VLAN 200, which is not desired because we need VLAN 200 to remain active and properly routed.

  Option B (set interfaces irb unit 100 family inet address 192-168.100.1): This command would incorrectly assign an IP address that does not correspond with the subnet of VLAN 100 (192.168.200.1 /24). This could create a misconfiguration,

  leading to routing issues.

  Data Center

  References:

  For a Data Center, proper VLAN management and static routing are crucial for ensuring that different network segments can communicate effectively, especially when dealing with separated subnets or zones like in different VLANs. This

  aligns with best practices in DCIM (Data Center InfrastructureManagement) which stress the importance of proper network configuration to avoid downtime and ensure seamless communication between all critical IT infrastructure

  components.

  Ensuring that the correct interfaces are associated with the correct VLANs and having the proper static routes in place are both essential steps in maintaining a robust and reliable data center network.

  This detailed analysis reflects best practices as noted in standard data center design and network configuration guides.