SD-WAN-Engineer Palo Alto Networks SD-WAN Engineer

Comprehensive and Detailed Explanation According to the Prisma SD-WAN Performance Policy Default Behavior documentation, the default action configured for applications (including real-time media) when a path experiences poor performance (violates the SLA thresholds for latency, jitter, or packet loss) is to Move Flows. The Prisma SD-WAN ION device continuously monitorsthe health of all available paths. If the active path for a media application degrades and fails to meet the specified SLA, the default policy dictates that the traffic should be steered (moved) to an alternate, compliant path that meets the performance criteria. While Forward Error Correction (FEC) is a powerful feature available in Prisma SD-WAN to mitigate packet loss for real-time applications, it is an optional action that must be explicitly enabled or configured within the performance policy rules. It is not the default action in the base system configuration; the primary default mechanism for handling performance issues is to leverage the multi-path fabric to switch to a better link. Reference: Prisma SD-WANAdministrator's Guide: Performance Policy Default Behavior.

Comprehensive and Detailed Explanation

The SITE_CONNECTIVITY_DOWN alarm is a high-severity alert indicating a total loss of overlay connectivity for a site.

It does not trigger if just one circuit fails (Option B), provided that other circuits are still up and maintaining VPNs. A single link failure would typically trigger a " Link Down " or " VPN Down " alarm, but the Site connectivity would remain " Up " (degraded).

It does not simply mean the device rebooted (Option A), although a reboot would cause it temporarily; the alarm specifically tracks the state of the VPN fabric.

The SITE_CONNECTIVITY_DOWN alarm specifically generates when all Secure Fabric Links (VPN tunnels) on the device are in the " Down " state. This means the branch is completely isolated from the rest of the SD-WAN network (Data Centers and other branches), even if the device itself might still be powered on and reachable via the controller (management plane). It signifies a " Blackout " of the data plane for that location.