When Microsoft Defender XDR and Sentinel are fully linked, if an incident is changed or closed in Sentinel, how does that change show up in Defender XDR, and what main problem does this solve for security teams?

When Microsoft Defender XDR, which is Microsoft's unified security operations platform providing Extended Detection and Response (XDR) capabilities across endpoints, identity, email, and cloud applications, is fully linked with Microsoft Sentinel, Microsoft's cloud-native Security Information and Event Management (SIEM) and Security Orchestration, Automation, and Response (SOAR) solution, a bi-directional synchronization is established for security incidents. If an incident is changed or closed in Sentinel, these updates are automatically reflected in Defender XDR. Specifically, when an incident originating from Defender XDR is ingested into Sentinel, a linked instance is created in Sentinel. If an analyst then modifies key attributes of this incident in Sentinel, such as its status (e.g., from 'Active' to 'Closed'), its assignment (e.g., to a specific analyst), or its classification (e.g., 'True Positive,' 'False Positive,' 'Benign'), these changes are automatically synchronized back to the corresponding original incident within Defender XDR. This means that the incident in Defender XDR will display the same updated status, owner, and classification as set in Sentinel. For example, if an incident is escalated to Sentinel and subsequently closed by an analyst in Sentinel with a 'True Positive - Resolved' classification, the same incident in Defender XDR will also update its status to 'Closed' and reflect that specific classification without any manual intervention. This process relies on the underlying integration layer facilitating near real-time communication between the two platforms. The main problem this solves for security teams is the elimination of fractured incident management and the establishment of a single source of truth for incident status and context across critical security platforms. Without this bi-directional synchronization, security analysts would be forced to manually update incident details, statuses, and assignments in both Defender XDR and Sentinel independently. This manual duplication of effort would lead to significant operational inefficiencies, inconsistent incident states between the two systems, a higher potential for human error, and analysts potentially wasting time investigating or working on outdated information. By ensuring a consistent state, the integration streamlines incident response workflows, reduces context switching for security personnel who may primarily work in one platform while leveraging the other, and guarantees that all teams have access to the most current and accurate incident information, thereby accelerating response times and improving overall security posture.