An application error spike was caused by a Service Account lacking permissions. You fixed it and want to be notified if it recurs. What should you do?

Creating a custom log-based metric for the specific error and using it in an Alerting Policy is the most effective solution. This allows you to define a metric that counts occurrences of the exact error message or pattern related to the Service Account's permission issue. An alerting policy can then be configured to trigger a notification when this metric exceeds a defined threshold within a specified time window, proactively informing you of a recurrence. Filtering logs in Logs Explorer is useful for ad-hoc investigation but doesn't provide proactive alerting. Creating a logs sink to BigQuery and a Data Studio dashboard offers historical analysis and visualization, but not real-time, automated alerting for specific error spikes. Granting the Service Account Project Owner role is a security anti-pattern, providing overly broad permissions and not addressing the need for specific error detection and alerting.