JN0-480 Exam Dumps - Juniper Certification Questions and 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

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

BGP is the protocol used to advertise EVPN routes. EVPN routes are a new type of BGP network layer reachability information (NLRI) that carry MAC address and IP prefix information for Ethernet VPNs. EVPN routes are exchanged between PEs using BGP multiprotocol extensions (MP-BGP) over MPLS, VXLAN, SR, or SRv6 tunnels. EVPN routes enable PEs to learn the reachability of MAC addresses and IP prefixes of different sites within the same EVPN instance. EVPN routes also support various features such as fast convergence, redundancy, aliasing, and inter-subnet routing. The other options are incorrect because:

• A. OSPF is wrong because OSPF is an interior gateway protocol (IGP) that is used to advertise IP routes within an autonomous system. OSPF is not used to advertise EVPN routes, which are a type of BGP NLRI that carry MAC address and IP prefix information for Ethernet VPNs.
• C. IS-IS is wrong because IS-IS is an interior gateway protocol (IGP) that is used to advertise IP routes and MPLS labels within an autonomous system. IS-IS is not used to advertise EVPN routes, which are a type of BGP NLRI that carry MAC address and IP prefix information for Ethernet VPNs.
• D. RIP is wrong because RIP is an interior gateway protocol (IGP) that is used to advertise IP routes within an autonomous system. RIP is not used to advertise EVPN routes, which are a type of BGP NLRI that carry MAC address and IP prefix information for Ethernet VPNs. References:
• EVPN Fundamentals
• RFC 9136 - IP Prefix Advertisement in Ethernet VPN (EVPN)
• EVPN Type-5 Routes: IP Prefix Advertisement
• Understanding EVPN Pure Type 5 Routes

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