JN0-480 Practice Exam Questions with Answers Data Center Specialist (JNCIS-DC) Certification

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)

VMware anomaly detection is a feature of Apstra that provides visibility and validation of the virtual network settings and the physical network settings in a VMware vSphere environment. To enable this feature, Apstra requires a connection to a vCenter server that manages the ESX/ESXi hosts and the VMs connected to the Apstra-managed leaf switches. The vCenter server must be configured under External Systems in the Apstra web interface, and the vCenter integration must be staged and committed in the blueprint. This allows Apstra to collect information about VMs, ESX/ESXi hosts, port groups, and VDS, and to flag any inconsistencies or mismatches that might affect VM connectivity. The other options are incorrect because:

• VMware anomaly detection is not on by default. It must be enabled by configuring a vCenter server under External Systems and adding a virtual infra to the blueprint.
• VMware anomaly detection does not require a VMware hypervisor with exports enabled. It only requires LLDP transmit to be enabled on the VMware distributed virtual switch to associate host interfaces with leaf interfaces.
• VMware anomaly detection does not require an Apstra server running on VMware. It can run on any supported platform, such as Linux, Windows, or Docker. References:
• VMware vCenter/vSphere Virtual Infra
• Anomalies (Service)
• A Better Experience: VMware + Juniper Apstra

The ztp.Json file on the Apstra ZTP server contains the configuration parameters for each device that is onboarded using ZTP. One of the parameters is the State, which can be one of the following values: init, ready, in_progress, done, error, or disabled. The State indicates the current status of the device in the ZTP process. For example, if the State is ready, it means that the device is ready to be onboarded by the Apstra ZTP server. If the State is done, it means that the device has completed the ZTP process and is managed by the Apstra server. The State can be manually set or changed in the ztp.Json file to control the behavior of the device during ZTP. For more information, see Apstra ZTP Configuration File. References:

• Apstra ZTP Configuration File
• Apstra ZTP Introduction
• Configure Apstra ZTP

A connectivity template is a set of configuration parameters that can be applied to a device or a group of devices in a blueprint. A blueprint is a logical representation of the network design and intent. A primitive is a basic unit of configuration that can be added to a connectivity template. A primitive can be a link, a peering, a policy, or a service. In the exhibit, the red-striped primitives indicate that further configuration is required for them to be compatible with the connectivity template design. The red stripes mean that the primitive is incomplete or invalid, and it needs to be edited or deleted. For example, the IP Link primitive needs to have the interface name and IP address specified for each end of the link. The other options are incorrect because:

• A. The gray-solid primitives indicate further configuration is required is wrong because the gray-solid primitives indicate that they are compatible with the connectivity template design. The gray color means that the primitive is valid and complete, and it does not need any further configuration.
• B. The gray-solid primitives indicate that they are incompatible with the connectivity template design is wrong because the gray-solid primitives indicate that they are compatible with the connectivity template design, as explained above.
• C. The red-striped primitives indicate that they are incompatible with the connectivity template design is wrong because the red-striped primitives indicate that further configuration is required, not that they are incompatible. The red stripes mean that the primitive is incomplete or invalid, but it can be fixed by editing or deleting it. References:
• Connectivity Templates
• Data Center Automation Using Juniper Apstra
• Config Rendering in Juniper Apstra

 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

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)

The deploy phase is the final step in the Juniper Apstra data center fabric design and deployment process. In this phase, you apply the Apstra-rendered configuration to the devices and verify the intent of the blueprint. Based on the web search results, we can infer the following actions are required during the deploy phase12:

• Assign device profiles to the blueprint. This action associates a specific vendor model to each logical device in the blueprint. Device profiles contain extensive hardware model details, such as form factor, ASIC, CPU, RAM, ECMP limit, and supported features. Device profiles also define how configuration is generated, how telemetry commands are rendered, and how configuration is deployed on a device. Device profiles enable the Apstra system to render and deploy the configuration according to the Apstra Reference Design34.
• Assign resources to the blueprint. This action allocates the physical devices, IP addresses, VLANs, and ASNs to the logical devices, networks, and routing zones in the blueprint. Resources can be assigned manually or automatically by the Apstra system. Assigning resources ensures that the blueprint has all the necessary elements to generate the configuration and deploy the fabric5 .
• Assign user roles to the blueprint. This action is not required during the deploy phase. User roles are defined at the system level, not at the blueprint level. User roles determine the permissions and access levels of different users in the Apstra system. User roles can be system-defined or custom-defined .
• Assign interface maps to the blueprint. This action is not required during the deploy phase. Interface maps are defined at the design phase, not at the deploy phase. Interface maps are objects that map the logical interfaces of a logical device to the physical interfaces of a device profile. Interface maps enable the Apstra system to generate the correct interface configuration for each device in the fabric . References:
• Deploy
• Deploy Device
• Device Profiles
• Juniper Device Profiles
• 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

In the case of IP Clos data center five-stage fabric design, the super spines are the devices that provide the highest level of aggregation in the network. They have two main roles:

• Super spines are used to interconnect two different data center pods. A pod is a cluster of leaf and spine devices that form a 3-stage Clos topology. A 5-stage Clos topology consists of multiple pods that are connected by the super spines. This allows for scaling the network to support more devices and bandwidth.
• Super spines connect to all spine devices within the five-stage architecture. The spine devices are the devices that provide the second level of aggregation in the network. They connect to the leaf devices, which are the devices that provide access to the end hosts. The super spines connect to all the spine devices in the network, regardless of which pod they belong to. This provides any-to-any connectivity between the pods and enables optimal routing and load balancing.

The following two statements are incorrect in this scenario:

• Super spines are used to connect leaf nodes within a data center pod. This is not true, because the leaf nodes are connected to the spine nodes within the samepod. The super spines do not connect to the leaf nodes directly, but only through the spine nodes.
• Super spines are always connected to an external data center gateway. This is not true, because the super spines are not necessarily involved in the external connectivity of the data center. The external data center gateway is a device that provides the connection to the outside network, such as the Internet or another data center. The external data center gateway can be connected to the super spines, the spine nodes, or the leaf nodes, depending on the design and the requirements of the network.

References:

• 5-stage Clos Architecture — Apstra 3.3.0 documentation
• 5-Stage Clos Architecture | Juniper Networks
• Extreme Fabric Automation Administration Guide

Time Voyager is a feature of Juniper Apstra that allows you to restore previous revisions of a blueprint, which is a logical representation of your network design and configuration. Time Voyager automatically saves the five most recent blueprint commits, which are the changes that you apply to the network. You can also manually save up to twenty-five revisions by keeping them, which prevents them from being overwritten by new commits. Therefore, the correct answer is B and D. Time Voyager retains the five most recent blueprint commits and Time Voyager retains up to twenty-five saved revisions. References: Time Voyager | Apstra 4.1 | Juniper Networks, Time Voyager Introduction | Apstra 4.2 | Juniper Networks, Juniper Apstra at a Glance | Flyer

When an agent installation is successful, devices are placed into the Out of Service Quarantined (OOS-QUARANTINED) state using the Juniper Apstra UI. This state means that the device is not yet managed by Apstra and has not been assigned to any blueprint. The device configuration at this point is called Pristine Config. To make the device ready for use in a blueprint, you need to acknowledge the device, which is a manual action that confirms the device identity and ownership. Acknowledging the device changes its status to Out of Service Ready (OOS-READY)12. References:

• Managing Devices
• AOS Device Configuration Lifecycle

A security policy is the feature that would be used to accomplish the task of controlling access to other virtual networks in the same routing zone using the Juniper Apstra UI. A security policy allows you to define rules that specify which traffic is allowed or denied between different virtual networks, IP endpoints, or routing zones. A security policy can be applied to one or more virtual networks in the same routing zone, and it can use various criteria to match the traffic, such as source and destination IP addresses, protocols, ports, or tags. A security policy can also support DHCP relay, which enables the forwarding of DHCP requests from one virtual network to another. The other options are incorrect because:

• A. interface policy is wrong because an interface policy is a feature that allows you to configure the interface parameters for the devices in a blueprint, such as interface names, speeds, types, or descriptions. An interface policy does not affect the access control between different virtual networks in the same routing zone.
• B. anti-affinity policy is wrong because an anti-affinity policy is a feature that allows you to prevent certain devices or logical devices from being placed in thesame rack or leaf pair in a blueprint. An anti-affinity policy is used to enhance the availability and redundancy of the network, not to control the access between different virtual networks in the same routing zone.
• C. routing policy is wrong because a routing policy is a feature that allows you to configure the routing parameters for the devices in a blueprint, such as routing protocols, autonomous system numbers, route filters, or route maps. A routing policy does not affect the access control between different virtual networks in the same routing zone, unless the routing policy is used to filter or modify the routes exchanged between different routing zones. References:
• Security Policy
• Interface Policy
• Anti-Affinity Policy
• Routing Policy

The attribute that enables Juniper Apstra to scale and manage thousands of devices with a single server instance is that Apstra is a distributed state system. This means that Apstra uses a graph database to store the network topology and configuration data in a distributed and replicated manner across multiple server nodes. This allows Apstra to handle large-scale networks with high performance, reliability, and availability. Apstra also uses a stateful orchestration engine that ensures the network state is always consistent with the intent of the blueprint, which is the logical representation of thenetwork design and behavior. Apstra can automatically detect and resolve any discrepancies between the desired and actual network state, as well as handle any changes or failures in the network. The other options are incorrect because:

• A. Apstra is installed as a cloud resource is wrong because Apstra can be installed either as a cloud resource or as an on-premises resource. Apstra is available as a virtual machine image that can be deployed on various hypervisors, such as VMware ESXi, QEMU/KVM, Microsoft Hyper-V, or Oracle VirtualBox. Apstra can also be deployed on public cloud platforms, such as Amazon Web Services (AWS) or Microsoft Azure. However, the installation method does not affect the scalability of Apstra, which is determined by the distributed state system architecture.
• B. Apstra is based on NGINX is wrong because Apstra is not based on NGINX, but on Python and Django. NGINX is a web server and reverse proxy that Apstra uses to serve the web user interface and the REST API. However, NGINX is not the core component of Apstra, and it does not affect the scalability of Apstra, which is determined by the distributed state system architecture.
• C. Apstra is available as an OVA is wrong because Apstra is available as an OVF, not an OVA. An OVF (Open Virtualization Format) is a standard format for packaging and distributing virtual machine images. An OVA (Open Virtual Appliance) is a single file that contains the OVF and the virtual disk images. Apstra provides an OVF file that can be imported into various hypervisors, such as VMware ESXi, QEMU/KVM, Microsoft Hyper-V, or Oracle VirtualBox. However, the availability of Apstra as an OVF does not affect the scalability of Apstra, which is determined by the distributed state system architecture. References:
• JUNIPER APSTRA ARCHITECTURE
• Apstra Server Requirements/References
• Juniper Networks Apstra 4.0 enhances the experience of users and operators

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