title: Azure Search - 503 Unavailable Alert
body: <p>I would like to understand how to detect <strong>503 - Service Unavailable</strong> errors from Azure Search <strong>via Azure Monitor</strong>.</p>
  
  <p>Sometimes one of our instances is not scaled enough to handle indexing jobs, but it is hard to tell on the application side (we only get a 503 when calling the service directly) and I could not find any metric on Azure Monitor. On the other hand, going to the portal directly, on the "Indexers" tab, we notice many of them failing with the aforementioned exception.</p>