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When working with logical devices, you specify where each port group is connected by selecting the port group layout and the port speed and role (s) for each port group. The Juniper Apstra UI offers two options to the operator for the port group role: unused and generic1.

Unused: This option means that the port group is not configured or used by Apstra. This can be useful for ports that are faulty, reserved, or not part of the data center fabric1.

Generic: This option means that the port group is configured with a generic role that is not specific to any device type or function. This can be useful for ports that are used for testing, troubleshooting, or custom purposes1. References:

Logical Devices

The cabling map is a graphical representation of the physical connections between the devices in the data center fabric. It shows the status of the cables, interfaces, and BGP sessions for each device. You can use the cabling map to verify and repair the cabling before deploying your blueprint. Based on the web search results, we can infer the following statements:

Apstra can use LLDP data from the spine-to-leaf fabric devices to update the connections in the cabling map. This is true because Apstra can collect LLDP data from the devices using the Generic Graph Collector processor and use it to update the cabling map automatically. LLDP is a protocol that allows devices to exchange information about their identity, capabilities, and neighbors12.

Apstra can use LLDP data from the leaf devices to update the leaf-to-generic connections in the cabling map. This is true because Apstra can also collect LLDP data from the leaf devices and use it to update the connections to the generic devices, such as routers, firewalls, or servers. Generic devices are devices that are not managed by Apstra but are part of the data center fabric23.

You must manually change the cabling map to update spine-to-leaf fabric links. This is false because Apstra can use LLDP data to update the spine-to-leaf fabric links automatically, as explained above. However, you can also manually change the cabling map to override the Apstra-generated cabling, if needed24.

You must manually change the cabling map to update leaf-to-generic links. This is false because Apstra can use LLDP data to update the leaf-to-generic links automatically, as explained above. However, you can also manually change the cabling map to override the Apstra-generated cabling, if needed24. References:

LLDP Overview

Edit Cabling Map (Datacenter)

Generic Devices

Import / Export Cabling Map (Datacenter)

According to the Juniper documentation1, a generic system is a device that is not managed by Juniper Apstra and does not have a specific role or type assigned to it. A generic system can be used to represent a server, a firewall, a load balancer, or any other device that is not part of the fabric. In the exhibit, the device shown is a generic system, as indicated by its role, system type, and management level. Therefore, the correct answer is B. The device shown is a generic system.

According to the Juniper documentation2, a LAG is a link aggregation group that bundles multiple physical interfaces into a single logical interface. A LAG can provide increased bandwidth, redundancy, and load balancing for the network traffic. In the exhibit, the device shown has four physical interfaces that are part of a LAG, as indicated by their description and li_type. The LAG is facing the leaf pair, which are the two switches that connect to the device. Therefore, the correct answer is C. Four physical interfaces exist in a LAG facing the leaf pair. References: Generic Systems (Datacenter Design), Form LAG | Apstra 4.1 | Juniper Networks

In the Juniper Apstra UI, the Resources menu allows you to create and manage global and local resources that are used for various elements of the network design and configuration. The Resources menu includes the following three types of resources that can be assigned to the network devices and virtual networks:

ASN pools: These are pools of autonomous system numbers (ASNs) that are used for the underlay routing protocol (EBGP) between the leaf and spine devices. You can create ASN pools with either 2-byte or 4-byte ASNs, and assign them to the logical devices in the blueprint.

VNI pools: These are pools of virtual network identifiers (VNIs) that are used for the overlay network (VXLAN) between the end hosts. You can create VNI pools with a range of VNIs, and assign them to the virtual networks in the blueprint.

IP address pools: These are pools of IPv4 or IPv6 addresses that are used for various purposes in the network, such as the loopback addresses for the devices, the IP prefixes for the virtual networks, the host IP addresses for the end hosts, and the gateway IP addresses for the IRB interfaces. You can create IP address pools with a range of IP addresses, and assign them to the logical devices and virtual networks in the blueprint.

The following two types of resources are not assigned under the Resources menu:

VTEP pools: These are not resources that can be created or assigned by the user. VTEPs are VXLAN tunnel endpoints that are automatically generated by the Apstra server based on the loopback IP addresses of the devices. VTEPs are used as the source and destination IP addresses for the VXLAN tunnels in the overlay network.

Logical device pools: These are not resources that can be created or assigned by the user. Logical device pools are groups of logical devices that share the same role, interface map, and resource assignments in the blueprint. Logical device pools are used to simplify the network design and configuration by applying the same settings to multiple devices.

References:

Resources Introduction

ASN Pools (Resources)

VNI Pools (Resources)

IP Address Pools (Resources)

According to the Juniper documentation1, a routing zone is an L3 domain, the unit of tenancy in multi-tenant networks. You create routing zones for tenants to isolate their IP traffic from one another, thus enabling tenants to re-use IP subnets. In addition to being in its own VRF, each routing zone can be assigned its own DHCP relay server and external system connections. You can create one or more virtual networks within a routing zone, which means a tenant can stretch its L2 applications across multiple racks within its routing zone. For virtual networks with Layer 3 SVI, the SVI is associated with a Virtual Routing and Forwarding (VRF) instance for each routing zone isolating the virtual network SVI from other virtual network SVIs in other routing zones. Therefore, the correct answer is D. A routing zone is used to enable the communication between two VNIs within a VRF. A routing zone is not used for L4-L7 inspection, securing routing protocols, or requiring firewalls. Those are not the purposes of a routing zone in Juniper Apstra software. References: Routing Zones

 Probes are the basic unit of abstraction in Intent-Based Analytics (IBA). They are used to collect, process, and analyze data from the network and raise anomalies based on specified conditions. Probes are composed of processors and stages that form a directed acyclic graph (DAG) of data flow. The following statements are correct about probes:

A. Default probes can be cloned, modified, and saved. This is true because Apstra provides a set of default probes that cover common use cases and scenarios. These probes can be cloned and modified to suit the specific needs of the user. The modified probes can be saved as new probes with different names and descriptions. This allows the user to customize and extend the functionality of the default probes.

D. Default probes are enabled, based on the intent for a blueprint. This is true because Apstra enables or disables the default probes automatically based on the intent of the blueprint. The intent of the blueprint is the high-level description of the desired state and behavior of the network. Apstra uses the intent to determine which default probes are relevant and applicable for the blueprint and enables them accordingly. For example, if the intent of the blueprint is to deployan EVPN-VXLAN fabric, Apstra will enable the default probes related to EVPN-VXLAN, such as EVPN-VXLAN Anomaly Detection, EVPN-VXLAN Fabric Health, and EVPN-VXLAN Fabric Validation. The following statements are incorrect about probes:

B. Only the variable parameters for default probes can be edited and saved. This is false because the user can edit and save any parameters for the default probes, not just the variable ones. The variable parameters are the ones that depend on the network topology, devices, or configuration, such as device names, interface names, IP addresses, VLAN IDs, etc. The user can also edit and save the fixed parameters, such as the duration, threshold, condition, etc. However, the user cannot edit and save the default probes directly. The user must clone the default probes first and then edit and save the cloned probes as new probes.

C. All default probes are enabled for all blueprints. This is false because Apstra does not enable all default probes for all blueprints. Apstra enables the default probes based on the intent of the blueprint, as explained above. This means that only the default probes that are relevant and applicable for the blueprint are enabled. For example, if the intent of the blueprint is to deploy a BGP IP fabric, Apstra will not enable the default probes related to EVPN-VXLAN, since they are not relevant for the blueprint. The user can also manually enable or disable the default probes as needed. References:

Probes

Create Probe

Intent-Based Analytics Overview

A pristine configuration in Juniper Apstra is the configuration file that is used to onboard a device into the Apstra software application. A pristine configuration contains the minimum settings that are required for the device to communicate with the Apstra server, such as the hostname, management IP address, username, password, and SSH key1. A pristine configuration has the following characteristics:

It is the configuration file placed on the device when decommissioning the device. This is because when a device is decommissioned from the Apstra software application, it is reverted back to its pristine configuration, which removes all the network configuration and services that were applied by the Apstra software application. This allows the device to be reused or repurposed for another network2.

It is the configuration file on a device before acknowledgment in Apstra. This is because when a device is onboarded into the Apstra software application, it is initially in the discovery state, which means that the device is discovered by the Apstra server, but not yet acknowledged by the user. In the discovery state, thedevice has the pristine configuration, which can be viewed and edited by the user. Once the user acknowledges the device, the device moves to the deployed state, which means that the device is ready to receive the network configuration and services from the Apstra software application3.

The following two statements are incorrect in this scenario:

It is the device’s currently active configuration. This is not true, because the pristine configuration is not the device’s currently active configuration, unless the device is in the discovery state or the decommissioned state. In the deployed state, the device’s currently active configuration is the network configuration and services that are applied by the Apstra software application, which are based on the blueprint and the intent3.

It is the device’s previously active configuration. This is not true, because the pristine configuration is not the device’s previously active configuration, unless the device is in the decommissioned state. In the discovery state, the pristine configuration is the device’s initial configuration, which may or may not be the same as the device’s previous configuration before being onboarded into the Apstra software application. In the deployed state, the device’s previously active configuration is the network configuration and services that were applied by the Apstra software application before the last commit3.

References:

Pristine Config

Decommission Device

Device States

A configlet is a small piece of configuration that can be applied to a device or a group of devices to make persistent changes that are not overwritten by Apstra. Configlets can be used to install manual changes that are not part of the Apstra rendered configuration, such as custom commands, scripts, or features. Configlets can be created, edited, and deleted from the Apstra GUI or CLI12. References:

Configlets Overview

Configlets User Guide

According to the Juniper documentation1, a predefined device profile is a configuration template that is shipped with Apstra software and supports most qualified Juniper devices. A predefined device profile cannot be changed, since any changes would be discarded and overwritten when you upgrade the Apstra server version. If you want to customize a predefined device profile, you can clone and edit it instead. Therefore, the correct answer is A. The changes you make to a predefined device profile will be discarded and overwritten when upgrading the Apstra server version. References: Edit Device Profile | Apstra 4.2 | Juniper Networks

VXLAN VNIs are virtual network identifiers that are used to identify and isolate Layer 2 segments in the overlay network. VXLAN VNIs have the following characteristics:

VNIs can have over 16 million unique values. This is because VXLAN VNIs are 24-bit fields that can range from 4096 to 16777214, according to the VXLAN standard1. This allows VXLAN to support a large number of Layer 2 segments and tenants in the network.

VNIs identify a broadcast domain. This is because VXLAN VNIs are used to group the end hosts that belong to the same Layer 2 segment and can communicate with each other using VXLAN tunnels. The VXLAN tunnels are established using the VTEP information that is distributed by EVPN. The VTEPs are VXLAN tunnel endpoints that perform the VXLAN encapsulation and decapsulation. The VXLAN tunnels preserve the Layer 2 semantics and support the broadcast, unknown unicast, and multicast traffic within the same VNI2.

The following two statements are incorrect in this scenario:

VNIs identify a collision domain. This is not true, because VXLAN VNIs do not identify a collision domain, which is a network segment where data packets can collide with each other. VXLAN VNIs identify a broadcast domain, which is a network segment where broadcast traffic can reach all the devices. Collision domains are not relevant in VXLAN networks, because VXLAN uses MAC-in-UDP encapsulation and IP routing to transport the Layer 2 frames over the Layer 3 network1.

VNIs are alphanumeric values. This is not true, because VXLAN VNIs are numeric values, not alphanumeric values. VXLAN VNIs are 24-bit fields that can range from 4096 to 16777214, according to the VXLAN standard1. Alphanumeric values are values that contain both letters and numbers, such as ABC123 or 1A2B3C.

References:

Virtual Extensible LAN (VXLAN) Overview

EVPN LAGs in EVPN-VXLAN Reference Architectures