https://www.nocentino.com/tags/failover/ Recent content in Failover on Anthony Nocentino's Blog Hugo en-us Sun, 19 Apr 2026 00:00:00 -0500 https://www.nocentino.com/posts/2026-04-19-planned-failover-walkthrough-sql-server-kubernetes-operator/ Sun, 19 Apr 2026 00:00:00 -0500 https://www.nocentino.com/posts/2026-04-19-planned-failover-walkthrough-sql-server-kubernetes-operator/ <p>When building the <a href="https://github.com/nocentino/sql-on-k8s-operator" target="_blank" rel="noopener external">sql-on-k8s-operator</a>, I wanted to make sure it could handle both planned and unplanned failovers. The easy case is a planned failover, where you deliberately move the primary role to another replica. The harder case is an unplanned failover, where the primary pod just disappears. The operator needs to handle both.</p> <p>I recently ran a full planned failover rotation on a three-replica SQL Server Availability Group managed by <a href="https://github.com/nocentino/sql-on-k8s-operator" target="_blank" rel="noopener external">sql-on-k8s-operator</a>, and I want to show you exactly what happens inside SQL Server and the operator during each hop. If you&rsquo;ve been following my <a href="https://www.nocentino.com/posts/2026-04-12-introducing-sql-on-k8s-operator/">Introducing the SQL Server on Kubernetes Operator</a> post, this is the logical next step: what does the error log actually look like during a planned failover, what does the operator do in response, and how long does the whole thing take?</p>