JN0-481 Online Practice Questions

Explanation:
Referring to the exhibit, the image shows the Racks table under the Staged menu in the Juniper Apstra UI. The Racks table displays the details of the racks that are used in the blueprint, such as the name, rack type, and date. The rack type is a resource that defines the type and number of leaf devices, access switches, and/or generic systems that are used in rack builds1. The image shows seven racks in the table, but only two rack types: BorderLeaf and ServerRack. Therefore, the statement D is correct in this scenario.
The following three statements are incorrect in this scenario:
- A. six. This is not true, because there are not six rack types in the table, but only two. The number six corresponds to the number of racks that have the same rack type: ServerRack.
- B. three. This is not true, because there are not three rack types in the table, but only two. The number
three does not correspond to any relevant information in the table or the image.
- C. seven. This is not true, because there are not seven rack types in the table, but only two. The number seven corresponds to the total number of racks in the table, not the rack types.
References:
- Rack Types (Datacenter Design)
- Racks (Staged)

Explanation:
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. If you’re using multiple routing zones, external system connections must be from leaf switches in the fabric. Routing between routing zones must be accomplished with external systems. Therefore, the correct answer is D. Use interconnection through an external gateway.
References: Routing Zones

Explanation:
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

Explanation:
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

Explanation:
In Juniper Apstra, a blueprint is a logical representation of the network design and configuration. When you create a new blueprint, you need to commit the changes to apply them to the network devices. However, committing the changes does not mean that the network is immediately updated and operational. It may take some time for the network to converge and reflect the new state of the blueprint. During this time, you may see some anomalies related to BGP in the main dashboard, which indicate that the BGP sessions are not established or stable between the devices. These anomalies are usually temporary and will disappear once the network converges and the BGP sessions are up and running. Therefore, the statement B is the most likely cause of these anomalies in this scenario.
The following three statements are less likely causes of these anomalies in this scenario:
- You have misconfigured ASNs. This is possible, but not very likely, because Juniper Apstra provides ASN pools that can be automatically assigned to the devices based on their roles. You can also manually specify the ASNs for the devices, but you need to ensure that they are unique and consistent with the network design. If you have misconfigured ASNs, you may see some anomalies related to BGP, but they will not disappear after the network converges. You will need to fix the ASNs and commit the changes again to resolve the anomalies.
- Spine-leaf links are incorrectly set. This is possible, but not very likely, because Juniper Apstra provides connectivity templates that can be used to define the spine-leaf links based on the interface maps. You can also manually specify the spine-leaf links, but you need to ensure that they are correct and match the physical cabling. If you have incorrectly set the spine-leaf links, you may see some anomalies related to BGP, but they will not disappear after the network converges. You will need to fix the spine-leaf links and commit the changes again to resolve the anomalies.


A generic system has not been configured. This is not relevant, because a generic system is a device that is not managed by Juniper Apstra, but is connected to the network. A generic system does not affect the BGP sessions between the devices that are managed by Juniper Apstra. If you have a generic system in your network, you need to configure it manually and ensure that it is compatible with the network design. A generic system does not cause any anomalies related to BGP in the main dashboard.
References:
- Blueprint Summaries and Dashboard
- BGP Session Flapping Probe
- Probe: BGP Session Monitoring