Paloalto Networks SD-WAN-Engineer Dumps Questions Answers

Comprehensive and Detailed Explanation

In the Prisma SD-WAN Data Center (DC) model, the terminology for BGP peers defines their role in the topology and how the system generates route maps.

Core Peer: This peer type is designated for the LAN-side connection (facing the DC Core Switch or internal Routers). Its primary purpose is to learn the subnets/prefixes hosted in the data center so the ION can advertise them to the remote branches. The system automatically creates route maps to facilitate this redistribution into the fabric.

Edge Peer: This peer type is designated for the WAN-side connection (facing the Edge Router or MPLS PE). Its primary purpose is to provide reachability to the underlay network.

Distinction: Selecting the correct type affects the default Route Maps and Prefix Lists generated by the controller. Configuring a Core Peer correctly ensures that the DC's internal subnets are properly learned and propagated to the overlay, whereas an Edge Peer configuration focuses on WAN next-hop reachability.

Comprehensive and Detailed Explanation

Prisma SD-WAN utilizes Link Quality Monitoring (LQM) to maintain a real-time health score for every WAN path.

To ensure the system knows the quality of a path before sending critical user traffic onto it, the ION device uses Active Probing.

Mechanism: The ION sends synthetic probe packets (typically UDP) across the Secure Fabric (VPN tunnels) and Direct Internet paths to its peers. These probes measure Latency, Jitter, and Packet Loss.

Active vs. Passive: While the system does use Passive Monitoring (observing actual user flows) when traffic is present to reduce overhead, Active Probes are essential for idle links or backup paths. Without active probing, the ION would have no data to make an intelligent steering decision for the first packet of a new video call. This ensures that "Real-Time" policies always have up-to-date metrics to select the best path immediately.

In modern enterprise environments, particularly those undergoing Mergers and Acquisitions (M&A), engineers often face the challenge of overlapping IP address space.4 Prisma SD-WAN addresses this by utilizing Virtual Routing and Forwarding (VRF) profiles.5 A VRF creates a separate routing table instance within the ION device, allowing multiple networks to coexist on the same physical hardware even if they use the same IP ranges.

To achieve end-to-end connectivity while maintaining strict segmentation, these VRF profiles must be correctly associated with site bindings.7 When a VRF is "bound" to a site, the ION device ensures that traffic belonging to that specific segment remains isolated not only locally (on the LAN) but also across the secure SD-WAN fabric. Prisma SD-WAN achieves this by encapsulating the traffic within the overlay tunnels and tagging it with a unique VRF identifier.8 This ensures that a "Corporate" VRF at Site A can only communicate with the "Corporate" VRF at Site B, effectively keeping "Guest" or "Acquisition" traffic completely separate.

This architectural approach is superior to traditional underlay segmentation (Option A) or simple interface-based virtual routers (Option D) because it provides a centralized, software-defined method to manage multi-tenancy. By using VRF profiles, administrators can define a global security and routing posture once and push it to all relevant sites.9 This simplifies the integration of new business units with conflicting IP schemes, as the Prisma SD-WAN controller handles the complex orchestration required to maintain path selection and security policies uniquely for each VRF across the entire global network.