Paloalto Networks SD-WAN-Engineer Dumps

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 supports Dynamic VPNs (Branch-to-Branch) even when both endpoints are behind Source NAT (e.g., typical broadband connections).

To achieve this, the ION devices utilize standard NAT Traversal techniques, specifically leveraging STUN (Session Traversal Utilities for NAT).

Discovery: Each ION communicates with the Cloud Controller (which acts as a STUN server/signaling broker). Through this communication, the controller observes the public IP and Port that the ION's traffic is coming from (the post-NAT address).

Signaling: The controller shares this public reachability information with the peer ION.

Hole Punching: The IONs then attempt to initiate connections to each other's discovered public IP/Port. This "UDP Hole Punching" allows them to establish a direct IPSec tunnel through the NAT devices without requiring static 1:1 NAT mapping or manual port forwarding on the provider routers, enabling mesh connectivity in commodity internet environments.

To ensure the stability and performance of the SD-WAN fabric, Prisma SD-WAN provides granular visibility into the health of each Instant-On Network (ION) appliance. While the solution is primarily application-defined, monitoring the underlying physical and system resources of the hardware or virtual instance is critical for proactive maintenance and troubleshooting.

At the individual device level, administrators can monitor system resource utilization, which includes CPU usage, memory (RAM) consumption, and disk space availability.1 High CPU or memory usage can indicate that the device is reaching its throughput limits or that a specific process (such as deep packet inspection) is overtaxing the system. Disk utilization is monitored to ensure there is sufficient space for local logs and system operations.

Beyond internal system health, interface-level metrics are essential. This includes monitoring interface bandwidth utilization to identify bottlenecks on WAN or LAN ports. Crucially, operational performance is also assessed through error and discard counters on each interface. High error rates or frequent packet discards often signal physical layer issues (like bad cabling), duplex mismatches, or upstream provider congestion. While VPN status and application flows are vital for network-wide visibility, the core health of an ION device is defined by these foundational system and interface metrics.

Monitoring these specific parameters allows network engineers to distinguish between an application performance issue caused by network latency and one caused by a local hardware resource constraint.