JN0-480 Sample Questions Answers

To answer this question, we need to understand the concept of ESI values in EVPN LAGs. An ESI is a 10-byte value that identifies an Ethernet segment, which is a set of links that connect a multihomed device (such as a server) to one or more PE devices (such as leaf switches) in an EVPN network. The same ESI value must be configured on all the PE devices that connect to the same Ethernet segment. This allows the PE devices to form an EVPN LAG, which supports active-active or active-standby multihoming for the device. The ESI value can be manually configured (type 0) or automatically derived from LACP (type 1) or other methods. In the exhibit, Server A is connected to two leaf switches (QFX 5210) using a LAG with LACP enabled. Server B is connected to three leaf switches (QFX 5120) using a LAG with LACP enabled. Based on this information, the following statements are correct about ESI values for the server connections to the fabric:

• C. A valid ESI value for Server A is 0x00.10.10.10.10.10.10.10.10.10. This is true because this ESI value can be automatically derived from the LACP configuration on the QFX 5210 devices. The LACP system ID is usually based on the MAC address of the device, and the LACP administrative key is a 2-byte value that identifies the LAG. For example, if the MAC address of the QFX 5210 device is 00:10:10:10:10:10 and the LAG ID is 10, then the LACP system ID is 00:10:10:10:10:10 and the LACP administrative key is 00:0A. The ESI value is then derived by concatenating the LACP system ID and the LACP administrative key, resulting in 00:10:10:10:10:10:00:0A. This ESI value can be represented in hexadecimal notation as 0x00.10.10.10.10.10.00.0A, or padded with zeros as 0x00.10.10.10.10.10.00.0A.00.00. This ESI value must be configured on both QFX 5210 devices that connect to Server A.
• D. A valid ESI value for Server B is 0x00.00.00.00.00.00.00.00.00.00. This is true because this ESI value is a reserved value that indicates a single-homed device. Server B is connected to three leaf switches (QFX 5120) using a LAG, but it is not multihomed to any of them. This means that Server B does not need an ESI value to form an EVPN LAG with any of the leaf switches. Instead, Server B can use the reserved ESI value of 0x00.00.00.00.00.00.00.00.00.00, which indicates that it is a single-homed device and does not participate in any EVPN LAG. This ESI value must be configured on all three QFX 5120 devices that connect to Server B. Thefollowing statements are incorrect about ESI values for the server connections to the fabric:
• A. A valid ESI value for Server A is 0x00.00.00.00.00.00.00.00.00.00. This is false because this ESI value is a reserved value that indicates a single-homed device. Server A is connected to two leaf switches (QFX 5210) using a LAG with LACP enabled, which means that it is multihomed to both of them. This means that Server A needs an ESI value to form an EVPN LAG with the leaf switches. The ESI value must be unique and non-zero for each Ethernet segment, so the reserved ESI value of 0x00.00.00.00.00.00.00.00.00.00 is not valid for Server A.
• B. A valid ESI value for Server B is 0x00.20.20.20.20.20.20.20.20.20. This is false because this ESI value is not derived from the LACP configuration on the QFX 5120 devices. Server B is connected to three leaf switches (QFX 5120) using a LAG with LACP enabled, but it is not multihomed to any of them. This means that Server B does not need an ESI value to form an EVPN LAG with any of the leaf switches. Instead, Server B can use the reserved ESI value of 0x00.00.00.00.00.00.00.00.00.00, which indicates that it is a single-homed device and does not participate in any EVPN LAG. The ESI value of 0x00.20.20.20.20.20.20.20.20.20 is not valid for Server B, and it may cause conflicts with other Ethernet segments that use the same ESI value. References:
• Ethernet Segment Identifiers, ESI Types, and LACP in EVPN LAGs
• Understanding Automatically Generated ESIs in EVPN Networks
• Ethernet Segment in EVPN: All You Need to Know

In the Juniper Apstra UI, you can create VNI pools for virtual networks that use VXLAN encapsulation in the overlay network. A VNI pool is a resource pool that contains a range of VNIs that can be assigned to the virtual networks. The valid VNI range for a VNI pool is 4096 through 16777214, according to the VXLAN standard1. Therefore, the statement B is correct in this scenario.

The following three statements are incorrect in this scenario:

• Any range is acceptable for the VNI pool. This is not true, because the VNI range has a lower and upper limit defined by the VXLAN standard1. The lower limit is 4096, and the upper limit is 16777214. Any VNI outside this range is invalid and cannot be used for VXLAN encapsulation.
• The valid VNI range is 2 through 4096. This is not true, because the VNI range does not start from 2, but from 4096. The VNIs from 2 to 4095 are reserved and cannot be used for VXLAN encapsulation1.
• The valid VNI range is 1 through 10000. This is not true, because the VNI range does not include 1, which is also reserved and cannot be used for VXLAN encapsulation1. The VNI range also does not end at 10000, but at 16777214, which is the maximum possible value for a 24-bit VNI field1.

References:

• VNI Pools (Resources)

To make the IP fabric a valid IP fabric, the connection between the two spine nodes must be removed. This is because an IP fabric is a network topology that uses a spine-leaf architecture, where the spine devices are only connected to the leaf devices, and the leaf devices are only connected to the spine devices. This creates a non-blocking, high-performance, and scalable network that supports Layer 3 routing protocols such as BGP or OSPF. The connection between the two spine nodes in the exhibit violates the spine-leaf design principle and introduces unnecessary complexity and potential loops in the network. The other options are incorrect because:

• A. The IP fabric must consist of only one device model throughout the fabric is wrong because an IP fabric can support different device models as long as they are compatible and interoperable. The exhibit shows two different models of QFX switches, which are both supported by Juniper Networks for IP fabric deployments.
• B. The connection between the two spine nodes must be increased to 40 Gbps is wrong because increasing the speed of the connection does not make the IP fabric valid. The connection between the two spine nodes should be removed, as explained above.
• C. The IP fabric connections must be increased to a speed greater than 10 Gbps is wrong because the speed of the connections does not affect the validity of theIP fabric. The IP fabric can use any speed that meets the bandwidth and performance requirements of the network. 10 Gbps is a common speed for IP fabric connections, but higher or lower speeds can also be used depending on the network design and devices. References:
• IP Fabric Underlay Network Design and Implementation
• IP Fabric Overview
• IP Fabric: Automated Network Assurance Platform

To create a new routing zone, you must specify the VRF Name, VLAN ID, and VNI for the routing zone. These are the mandatory fields in the user interface shown in the exhibit. The VRF Name is the name of the L3 domain that isolates the IP traffic of the routing zone from other routing zones. The VLAN ID is the identifier for the VLAN tagged Layer 3 links on external connections. The VNI is the VxLAN Network Identifier associated with the routing zone. The Routing Policies are optional fields that allow you to configure import and export route targets for the routing zone. These are onlyapplicable for EVPN routing zones, which use MP-EBGP as the overlay control protocol. The other options are incorrect because:

• A. VRF Name only is wrong because you also need to specify the VLAN ID and VNI for the routing zone.
• B. VRF Name and Routing policies is wrong because you also need to specify the VLAN ID and VNI for the routing zone. Routing policies are optional and only relevant for EVPN routing zones.
• D. VRF Name, VLAN ID, VNI, Routing Policies is wrong because Routing Policies are optional and not required to create a new routing zone. References:
• Routing Zones (Virtual)
• Data Center Automation Using Juniper Apstra

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)

Referring to the exhibit, the image shows a user interface of the Juniper Apstra software application, which is used for network management and configuration. The image shows the Virtual Networks table under the Resources menu, which displays the details of the VLANs and VXLANs in the network. The table has 11 columns, but only 9 are visible in the image. The other two columns are IPv6 Connectivity and IPv6 Subnet, which are hidden by default. To display the IPv6 subnets for all of the listed VXLANs, the user needs to select Columns, then select IPv6 Subnet. This will show the IPv6 Subnet column in the table, which will display the IPv6 addresses assigned to the VXLANs from the IPv6 pools. For more information, see Virtual Networks (Resources). References:

• Virtual Networks (Resources)
• IPv6 Pools (Resources)
• Apstra User Guide

According to the Juniper documentation1, the Resources menu in the Juniper Apstra UI allows you to create and manage various types of resources that are assigned to different elements of the network. Resources include the following types:

• IPv4 (including Host IPv4)
• IPv6 (including Host IPv6)
• ASN (autonomous system number)
• VNI (virtual network identifier)
• VLAN (virtual local area network)
• Integer (used for pool type VLAN in local pools in Freeform blueprints)

Therefore, the correct answer is C and D. ASN pools and IP pools are two types of resources that can be created in the Resources menu. Bridge domain identifier (BDI) and DHCP pools are not applicable in this scenario, because they are not part of the resources types supported by Juniper Apstra. References: Resources Introduction | Apstra 4.1 | Juniper Networks

According to the Juniper documentation1, an interface map is a configuration template that maps interfaces between logical devices and physical hardware devices (represented with device profiles) while adhering to vendor specifications. An interface map specifies a connection between the interfaces of two devices, such as a leaf and a spine, a leaf and a server, or a leaf and an external gateway. An interface map can also specify port transformations, such as breaking out a 40 GbE port into four 10 GbE ports, or disabling unused ports. An interface map can be used to achieve the intended network configuration rendering and to enable features such as LAG, ESI-LAG, or MLAG. Therefore, the correct answer is B. An interface map specifies a connection between the interfaces of two devices. References: Interface Maps (Datacenter Design)

Device A serves as a spine in an IP fabric. An IP fabric is a network architecture that uses a spine-leaf topology to provide high performance, scalability, and reliability for data center networks. A spine-leaf topology consists of two layers of devices: spine devices and leaf devices. Spine devices are the core devices that interconnect all the leaf devices using equal-cost multipath (ECMP) routing. Leaf devices are the edge devices that connect to the servers, storage, or other network devices. In the exhibit, Device A is connected to four leaf devices using multiple links, which indicates that it is a spine device. The other options are incorrect because:

• A. leaf is wrong because a leaf device is an edge device that connects to the servers, storage, or other network devices. In the exhibit, Device A is not connected to any servers, storage, or other network devices, but only to four leaf devices, which indicates that it is not a leaf device.
• C. super spine is wrong because a super spine device is a higher-level device that interconnects multiple spine devices in a large-scale IP fabric. A super spine device is typically used when the number of leaf devices exceeds the port density of a single spine device. In the exhibit, Device A is not connected to any other spine devices, but only to four leaf devices, which indicates that it is not a super spine device.
• D. server is wrong because a server device is a compute or storage device that connects to a leaf device in an IP fabric. A server device is typically the end host that provides or consumes data in the network. In the exhibit, Device A is not connected to any leaf devices, but only to four leaf devices, which indicates that it is not a server device. References:
• IP Fabric Underlay Network Design and Implementation
• IP Fabric Overview
• IP Fabric Architecture

The Juniper Apstra Rendered configuration is the configuration that is generated from the staged blueprint and applied to the devices in the network. The Rendered configuration is dynamically rendered at commit time, which means that it is created on the fly based on the latest changes and validations in the blueprint. The Rendered configuration is not stored in any database, but it can be viewed in the Apstra UI or downloaded as a file. The Rendered configuration reflects the desired state of the network as defined by the intent of the blueprint. The other options are incorrect because:

• A. It is built at commit time and stored in a MySQL database is wrong because the Rendered configuration is not stored in any database, let alone a MySQLdatabase. Apstra uses a graph database to store the network topology and configuration data, not a relational database like MySQL.
• B. It is stored in a NoSQL database and incrementally updated is wrong because the Rendered configuration is not stored in any database, let alone a NoSQL database. Apstra uses a graph database to store the network topology and configuration data, not a non-relational database like NoSQL. The Rendered configuration is not incrementally updated, but dynamically rendered at commit time.
• D. It is rendered from the graph database and stored locally is wrong because the Rendered configuration is not rendered from the graph database, but from the staged blueprint. The graph database stores the network topology and configuration data, but the Rendered configuration is generated from the blueprint, which is a logical representation of the network design and intent. The Rendered configuration is not stored locally, but it can be downloaded as a file if needed. References:
• Config Rendering in Juniper Apstra
• AOS Device Configuration Lifecycle
• Configlets (Datacenter Design)

To keep virtual networks isolated from each other within the Juniper Apstra system, you can use one or more of the following methods:

• Enable Security Policy for virtual networks in the same Routing Zone. This allows you to define rules that control the traffic flow between different virtual networks within the same routing zone. You can specify the source and destination virtual networks, the protocol, the port, and the action (allow or deny) for each rule. The security policy is applied on the ingress interface of the leaf devices1.
• Use Connectivity Templates to block access within the same Routing Zone. This allows you to customize the connectivity between different racks within the same routing zone. You can create templates that define the link type, the routing protocol, and the access control list(ACL) for each rack pair. The ACL can be used to filter the traffic based on the source and destination IP addresses, the protocol, and the port2.
• Put each network in different Routing Zones. This allows you to create logical boundaries between different virtual networks based on the route target (RT) values. A routing zone is a collection of virtual networks that share the same RT for importing and exporting routes. Virtual networks in different routing zones do not exchange routes with each other, unless you configure remote EVPN gateways to connect them3. References:
• Security Policy
• Connectivity Templates
• Routing Zones

According to the Juniper documentation1, a configlet is a configuration template that augments Apstra’s reference design with non-native device configuration. They consist of one or more generators. Each generator specifies a NOS type (config style), when to render the configuration, and CLI commands (and file name as applicable). Some applications for configlets include the following:

• Syslog
• SNMP access policy
• TACACS / RADIUS
• Management ACLs
• Control plane policing
• NTP
• Username / password

Therefore, the correct answer is C and D. syslog configuration and NTP configuration. These are examples of non-native device configuration that can be added using a configlet. Static route configuration and policy configuration are not applicable in this scenario, because they are part of the reference design configuration that should not be replaced or modified by a configlet. References: Configlets (Datacenter Design), Configlet Examples (Design)

 According to the Juniper documentation1, the Revert button is located on the Uncommitted tab of the blueprint page. The Uncommitted tab shows the changes that have been staged but not yet committed to the network. The Revert button allows you to discard any uncommitted changes and revert to the last committed state of the blueprint. This is useful if you want to cancel the changes that you have made or if you want to start over with a fresh slate. Therefore, the correct answer is B. The Revert button deletes any uncommitted changes within Apstra. References: Commit / Revert Changes to Blueprint | Apstra 4.2 | Juniper Networks

According to the Juniper documentation1, a template is a configuration template that defines a network’s policy intent and structure. A template can be either rack-based or pod-based, depending on the type and number of racks and pods in the network design. A template includes the following details:

• Policies: These are the parameters that apply to the entire network, such as the overlay control protocol, the ASN allocation scheme, and the underlay type.
• Structure: This is the physical layout of the network, such as the type and number of racks, pods, spines, and leaves. The structure also defines the leaf-to-spine interconnection, which is the number and type of links between the leaf and spine devices. The leaf-to-spine interconnection can be either single or dual, depending on the redundancy and bandwidth requirements.

Therefore, the correct answer is A. the leaf-to-spine interconnection. This is a component that is defined in a template, as it determines the physical connectivity of the network. The speed of the links, the number of spine devices, and the definition of IP pools are not components that are defined in a template, as they are either derived from the device profiles, the resource pools, or the blueprint settings. References: Templates Introduction | Apstra 4.2 | Juniper Networks

According to the Juniper documentation1, a five-stage Clos architecture allows for large-scale topologies with an additional aggregation layer that interconnects multiple pods into a single fabric. A pod is a group of racks that share the same spine devices. A rack is a group of leaf devices that connect to the same servers. To create a five-stage Clos network using Juniper Apstra, you need to choose the pod-based fabric type in the template creation wizard. This will allow you to specify the number of pods, planes, spines, and leaves for your network design. Therefore, the correct answer is D. pod-based. References: 5-Stage Clos Architecture | Apstra 4.1 | Juniper Networks

The cable 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 cable map to identify and troubleshoot any cable, interface, or BGP anomalies that may occur in the fabric. You can also filter the cable map by device name, device type, device role, device state, cable state, interface state, or BGP state12. References:

• Cable Map Overview
• Cable Map User Guide