diff --git a/x-pack/plugins/monitoring/server/lib/errors/known_errors.js b/x-pack/plugins/monitoring/server/lib/errors/known_errors.js
index 6f02d0b0b26c0e..17bcdd0414adfc 100644
--- a/x-pack/plugins/monitoring/server/lib/errors/known_errors.js
+++ b/x-pack/plugins/monitoring/server/lib/errors/known_errors.js
@@ -47,5 +47,7 @@ export function isKnownError(err) {
 
 export function handleKnownError(err) {
   err.message = err.message + ': ' + (err.description || mapTypeMessage[err.constructor.name]);
-  return boomify(err, { statusCode: KNOWN_ERROR_STATUS_CODE });
+  let statusCode = err.statusCode || err.status;
+  statusCode = statusCode !== 500 ? statusCode : KNOWN_ERROR_STATUS_CODE;
+  return boomify(err, { statusCode });
 }
diff --git a/x-pack/plugins/monitoring/server/plugin.ts b/x-pack/plugins/monitoring/server/plugin.ts
index 0fa1a5bf144ac9..a45e80ac71d655 100644
--- a/x-pack/plugins/monitoring/server/plugin.ts
+++ b/x-pack/plugins/monitoring/server/plugin.ts
@@ -10,12 +10,6 @@ import { i18n } from '@kbn/i18n';
 import { has, get } from 'lodash';
 import { UsageCollectionSetup } from 'src/plugins/usage_collection/server';
 import { TelemetryCollectionManagerPluginSetup } from 'src/plugins/telemetry_collection_manager/server';
-import {
-  LOGGING_TAG,
-  KIBANA_MONITORING_LOGGING_TAG,
-  KIBANA_ALERTING_ENABLED,
-  KIBANA_STATS_TYPE_MONITORING,
-} from '../common/constants';
 import {
   Logger,
   PluginInitializerContext,
@@ -27,7 +21,15 @@ import {
   CoreStart,
   IRouter,
   IClusterClient,
-} from '../../../../src/core/server';
+  CustomHttpResponseOptions,
+  ResponseError,
+} from 'kibana/server';
+import {
+  LOGGING_TAG,
+  KIBANA_MONITORING_LOGGING_TAG,
+  KIBANA_ALERTING_ENABLED,
+  KIBANA_STATS_TYPE_MONITORING,
+} from '../common/constants';
 import { MonitoringConfig } from './config';
 // @ts-ignore
 import { requireUIRoutes } from './routes';
@@ -92,6 +94,16 @@ interface IBulkUploader {
 // This is used to test the version of kibana
 const snapshotRegex = /-snapshot/i;
 
+const wrapError = (error: any): CustomHttpResponseOptions<ResponseError> => {
+  const options = { statusCode: error.statusCode ?? 500 };
+  const boom = Boom.isBoom(error) ? error : Boom.boomify(error, options);
+  return {
+    body: boom,
+    headers: boom.output.headers,
+    statusCode: boom.output.statusCode,
+  };
+};
+
 export class Plugin {
   private readonly initializerContext: PluginInitializerContext;
   private readonly log: Logger;
@@ -369,12 +381,16 @@ export class Plugin {
               },
             },
           };
-
-          const result = await options.handler(legacyRequest);
-          if (Boom.isBoom(result)) {
-            return res.customError({ statusCode: result.output.statusCode, body: result });
+          try {
+            const result = await options.handler(legacyRequest);
+            return res.ok({ body: result });
+          } catch (err) {
+            const statusCode: number = err.output?.statusCode || err.statusCode || err.status;
+            if (Boom.isBoom(err) || statusCode !== 500) {
+              return res.customError({ statusCode, body: err });
+            }
+            return res.internalError(wrapError(err));
           }
-          return res.ok({ body: result });
         };
 
         const validate: any = get(options, 'config.validate', false);
diff --git a/x-pack/plugins/monitoring/server/routes/api/v1/cluster/cluster.js b/x-pack/plugins/monitoring/server/routes/api/v1/cluster/cluster.js
index 8d6fe04cdb7bd7..240cb84539dbf8 100644
--- a/x-pack/plugins/monitoring/server/routes/api/v1/cluster/cluster.js
+++ b/x-pack/plugins/monitoring/server/routes/api/v1/cluster/cluster.js
@@ -46,9 +46,13 @@ export function clusterRoute(server) {
         codePaths: req.payload.codePaths,
       };
 
-      return getClustersFromRequest(req, indexPatterns, options).catch(err =>
-        handleError(err, req)
-      );
+      let clusters = [];
+      try {
+        clusters = await getClustersFromRequest(req, indexPatterns, options);
+      } catch (err) {
+        throw handleError(err, req);
+      }
+      return clusters;
     },
   });
 }