Juniper JN0-683 Practice Test - Questions Answers, Page 5

DHCP Behavior in Factory-Default Configuration:

Option B: In the factory-default configuration, Juniper switches are designed to send DHCP requests on all operational interfaces. This behavior ensures that the switch can obtain an IP address for management and further configuration from any available DHCP server.

Option D: The DHCP server can provide additional configuration parameters, including the required Junos version. This allows for automated provisioning and ensures that the switch is running the correct software version.

Conclusion:

Option B: Correct---The switch will use any operational interface to request an IP address via DHCP.

Option D: Correct---The DHCP server can specify Junos version requirements, enabling automated software management.

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:

Shell scripts are often used for general automation tasks.

Python is 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.

Understanding ERB Architecture:

ERB (Edge Routed Bridging) architecture is a network design where the routing occurs at the edge (leaf devices) rather than in the spine devices. In a VXLAN overlay network with EVPN as the control plane, leaf devices typically act as both Layer 2 (L2) and Layer 3 (L3) VXLAN gateways.

Placement of VXLAN Gateways:

Option B: All leaf devices will have L2 VXLAN gateways to handle the bridging of VLAN traffic into VXLAN tunnels.

Option C: All leaf devices will also have L3 VXLAN gateways to route traffic between different VXLAN segments (VNIs) and external networks.

Option E: Spine devices in an ERB architecture generally do not function as VXLAN gateways. They primarily focus on forwarding traffic between leaf nodes and do not handle VXLAN encapsulation/decapsulation.

Conclusion:

Option B: Correct---All leaf devices will have L2 VXLAN gateways.

Option C: Correct---All leaf devices will have L3 VXLAN gateways.

Option E: Correct---Spine devices will not act as VXLAN gateways

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.

Clos IP Fabric Design:

A Clos fabric is a network topology designed for scalable, high-performance data centers. It is typically arranged in multiple stages, providing redundancy, high bandwidth, and low latency.

Three-Stage Clos Fabric:

Option B: A three-stage Clos fabric, consisting of leaf, spine, and super spine layers, is widely used in data centers. This design scales well and allows for easy expansion by adding more leaf and spine devices as needed.

Super Spines for Scalability:

Option D: Using high-capacity devices like the QFX5700 Series as super spines can handle the increased traffic demands in large data centers and support future growth. These devices provide the necessary bandwidth and scalability for large-scale deployments.

Conclusion:

Option B: Correct---A three-stage Clos fabric is a proven design that addresses growth and scalability concerns in large data centers.

Option D: Correct---QFX5700 Series devices are suitable for use as super spines in large-scale environments due to their high performance.

Telemetry in Data Centers:

Telemetry allows for real-time monitoring of network devices by collecting and exporting data such as interface statistics, routing table updates, and other key metrics.

Option A: JTI (Junos Telemetry Interface) OpenConfig sensors use a vendor-neutral data model, which is important for ensuring compatibility across different network devices and systems. OpenConfig is an industry-standard model, which facilitates integration with various telemetry collection systems.

Conclusion:

Option A: Correct---OpenConfig sensors provide a vendor-neutral solution for telemetry, ensuring broad compatibility and flexibility in data center environments.

Understanding the Configuration:

The exhibit shows configurations for two VRFs (Customer_A and Customer_B) with specific VLANs and VNIs assigned. Each VRF has interfaces (IRBs) associated with particular VLANs.

Communication Between VLANs and Routing Instances:

Option B: VLAN 400 (irb.400) is part of Customer_B, and there is no direct connection or routing between Customer_A and Customer_B in the configuration provided. Therefore, devices in irb.400 cannot communicate directly with devices in the Customer_A routing instance.

Option D: Since irb.400 (VLAN 400) and irb.800 (VLAN 800) are part of the same routing instance (Customer_B), they can communicate over the fabric using VXLAN encapsulation.

Conclusion:

Option B: Correct---There is no direct communication between devices in irb.400 (Customer_B) and routing instance Customer_A.

Option D: Correct---Devices in VLAN 400 and VLAN 800 can communicate within the Customer_B routing instance over the fabric.

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 typically used 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.

Understanding the Problem:

Host1 (10.1.1.1) is failing to communicate with Host2 (10.1.2.1) within an EVPN-VXLAN environment using ERB architecture.

Analysis of the Exhibit:

The provided output includes information from the show route forwarding-table matching command for IP 10.1.2.1. The next hop is shown as vtep.32769, which indicates that the traffic destined for 10.1.2.1 is being forwarded into the VXLAN tunnel with the correct VTEP (VXLAN Tunnel Endpoint).

Conclusion:

Option B: Correct---The traffic from Host1 is entering the VXLAN tunnel, as evidenced by the next hop pointing to a VTEP. However, the issue could lie elsewhere, possibly with the remote VTEP, routing configurations, or the receiving leaf/spine devices.