B. Use filter-based forwarding.

Answer DescriptionExplanation:

Controlling Traffic Within a Tenant's Network:

The requirement is to limit access to specific traffic types within a tenant’s network without routing all tenant traffic through a firewall. This requires a selective method that can direct specific types of traffic to different paths based on the nature of the traffic.

Filter-Based Forwarding (FBF):

FBF is a technique that allows for routing decisions based on filters applied to the traffic, such as matching on source IP addresses, destination IP addresses, or even specific application types (like HTTP or FTP). This allows specific types of traffic to be forwardedto a specific next hop (e.g., a firewall) without affecting the entire traffic flow within the tenant's network.

Conclusion:

Option B:Correct—Filter-based forwarding allows for granular control of traffic, ensuring that only specific types of traffic within the tenant's network are redirected through a firewall, satisfying the requirement.

A. drop
D. log
E. shutdown

Answer DescriptionExplanation:

MAC Move Limiting:

MAC move limiting is a security feature used in network switches to detect and mitigate rapid changes in MAC address locations, which could indicate a network issue or an attack such as MAC flapping or spoofing.

When a MAC address is learned on a different interface than it was previously learned, the switch can take various actions to prevent potential issues.

Available Actions:

A. drop:This action drops packets from the MAC address if it violates the move limit, effectively blocking communication from the offending MAC address.

D. log:This action logs the MAC move event without disrupting traffic, allowing network administrators to monitor and investigate the event.

E. shutdown:This action shuts down the interface on which the MAC address violation occurred, effectively stopping all traffic on that interface to prevent further issues.

Other Actions (Not Correct):

B. filter:Filtering is not typically associated with MAC move limiting; it generally refers to applying ACLs or other mechanisms to filter traffic.

C. enable:This is not an action related to MAC move limiting, as it does not represent a specific reaction to a MAC move event.

Data Center References:

MAC move limiting is crucial for maintaining network stability and security, particularly in environments with dynamic or large-scale Layer 2 networks where MAC addresses might frequently change locations.

C. Use IRB interfaces with the same IP and MAC address.

Answer DescriptionRedundant Gateways in EVPN-VXLAN:

In an EVPN-VXLAN environment, providing redundant gateway functionality typically involves the use of Anycast Gateway. This allows multiple PEs (Provider Edge devices) to use the same IP address and MAC address for the gateway, enabling seamless failover and redundancy without IP conflicts.

Conserving Address Space:

Using the same IP address across multiple PEs conserves address space because only one IP address is needed for the gateway function, regardless of the number of PEs. The shared MAC address ensures that ARP resolution and forwarding behavior are consistent across all the PEs.

Conclusion:

Option C:Correct—Using IRB interfaces with the same IP and MAC address across all PEs satisfies the need for redundancy while conserving address space.

OptionsA, B,andDintroduce unnecessary complexity or do not fully utilize the efficient Anycast Gateway approach, which is best practice for conserving IP space and providing redundancy.

B. You need to configure a next-hop self policy.
D. You need to configure multipath multiple-as.

Answer DescriptionExplanation:

Issue Overview:

The leaf devices in an IP fabric using eBGP are advertising and receiving all routes, but the routes are not being installed in the routing table and are marked as hidden. Thistypically indicates an issue with the BGP configuration, particularly with next-hop handling or AS path concerns.

Corrective Actions:

B. You need to configure a next-hop self policy:This action ensures that the leaf devices modify the next-hop attribute to their own IP address before advertising routes to their peers. This is particularly important in eBGP setups where the next-hop may not be directly reachable by other peers.

D. You need to configure multipath multiple-as:This setting allows the router to accept multiple paths from different autonomous systems (ASes) and use them for load balancing. Without this, the BGP process might consider only one path and mark others as hidden.

Incorrect Statements:

A. You need to configure as-override:AS-override is used to replace the AS number in the AS-path attribute to prevent loop detection issues in MPLS VPNs, not in a typical eBGP IP fabric setup.

C. You need to configure loops 2:There is no specific BGP command loops 2 relevant to resolving hidden routes in this context. It might be confused with allowas-in, which is used to allow AS path loops under certain conditions.

Data Center References:

Proper BGP configuration is crucial in IP fabrics to ensure route propagation and to prevent routes from being marked as hidden. Configuration parameters like next-hop self and multipath multiple-as are common solutions to ensure optimal route installation and load balancing in a multi-vendor environment.

C. Symmetric routing supports higher scaling numbers.
D. Asymmetric routing routes traffic on the egress switch.

Answer DescriptionExplanation:

Symmetric vs. Asymmetric Routing in EVPN-VXLAN:

Symmetric Routing:Traffic enters and exits the VXLAN network through the same VTEP, regardless of the source or destination. This approach simplifies routing decisions, especially in large networks, and is generally more scalable.

Asymmetric Routing:The routing occurs on the egress VTEP. This method can be simpler to deploy in smaller environments but becomes complex as the network scales, particularly with larger numbers of VNIs and VLANs.

Correct Statements:

C. Symmetric routing supports higher scaling numbers:Symmetric routing is preferred in larger EVPN-VXLAN deployments because it centralizes routing decisions, which can be more easily managed and scaled.

D. Asymmetric routing routes traffic on the egress switch:This is accurate, as asymmetric routing means the routing decision is made at the final hop, i.e., the egress VTEP before the traffic reaches its destination.

Incorrect Statements:

A. Symmetric routing needs an extra VLAN with an IRB interface for each L3 VRF instance:This is not accurate. Symmetric routing does not require an extra VLAN per VRF; rather, it uses the same VLAN/VNI across the network, simplifying routing and VLAN management.

B. Asymmetric routing is easier to monitor because of the transit VNI:Asymmetric routing is not necessarily easier to monitor; in fact, it can add complexity due to the split routing logic between ingress and egress points.

Data Center References:

The choice between symmetric and asymmetric routing in an EVPN-VXLAN environment depends on network size, complexity, and specific operational requirements. Symmetric routing is generally more scalable and easier to manage in large-scale deployments.

B. the MAC address for each OFX5120
D. the management IP address for each OFX5120

Answer DescriptionExplanation:

Zero Touch Provisioning (ZTP):

ZTP allows for the automated configuration of network devices, like QFX Series switches, without manual intervention. During ZTP, a switch will obtain its configuration from a DHCP server and then download the required software and configuration files from a specified server (e.g., FTP, HTTP).

DHCP Server Configuration:

Option B:The DHCP server needs to know theMAC address for each QFX5120to provide a specific configuration based on the device identity. By mapping the MAC address to a particular configuration, the DHCP server can ensure that each switch gets the correct configuration.

Option D:Themanagement IP address for each QFX5120must also be assigned by the DHCP server. This IP address allows the device to communicate on the network and access the configuration files and other required resources during the ZTP process.

Conclusion:

Option B:Correct—MAC addresses allow the DHCP server to identify each QFX5120 and assign the appropriate configuration.

Option D:Correct—Management IP addresses are essential for network communication during ZTP.

B. using UDP
D. using gRPC

Answer DescriptionJunos Telemetry Interface (JTI):

The Junos Telemetry Interface is a framework that allows network operators to collect real-time telemetry data from Juniper devices. This data can be used for monitoring, analytics, and network automation.

Data Export Methods:

Option B:UDP (User Datagram Protocol)is a lightweight, connectionless protocol used for exporting telemetry data quickly with minimal overhead. While it doesn't guarantee delivery, it is suitable for high-speed data transfer where occasional packet loss is acceptable.

Option D:gRPC (gRPC Remote Procedure Call)is a modern, high-performance method for data export that supports streaming and remote procedure calls, making it ideal for more complex telemetry data use cases.

Conclusion:

Option B:Correct—UDP is supported for exporting telemetry data.
Option D:Correct—gRPC is also supported, offering advanced streaming capabilities

C. show interfaces terse vtep.32770 statistics

Answer DescriptionVXLAN Traffic Verification:

To ensure VXLAN traffic from the xe-0/0/12 interface is correctly encapsulated by the logical vtep.32770 and sent to a remote leaf device, it is essential to monitor the relevant interface statistics.

The command show interfaces terse vtep.32770 statistics provides a concise overview of the traffic statistics for the specific VTEP interface, which can help verify whether traffic is being correctly encapsulated and transmitted.

Explanation:

This command is particularly useful for quickly checking the traffic counters and identifying any potential issues with VXLAN encapsulation or transmission.

It allows you to confirm that traffic is flowing as expected, by checking the transmitted and received packet counters.

Data Center References:

Monitoring interface statistics is a crucial step in troubleshooting and validating network traffic, particularly in complex overlay environments like EVPN-VXLAN.