diff --git a/include/maxscale/monitor.h b/include/maxscale/monitor.h
index 4b0b56941..e23cea728 100644
--- a/include/maxscale/monitor.h
+++ b/include/maxscale/monitor.h
@@ -385,14 +385,15 @@ void load_server_journal(MXS_MONITOR *monitor, MXS_MONITORED_SERVER **master);
 MXS_MONITORED_SERVER* mon_get_monitored_server(const MXS_MONITOR* mon, SERVER* search_server);
 
 /**
- * Get an array of monitored servers. All the servers defined in the config setting must be monitored by
- * the given monitor.
+ * Get an array of monitored servers. If a server defined in the config setting is not monitored by
+ * the given monitor, that server is ignored and not inserted into the output array.
  *
  * @param params Config parameters
  * @param key Setting name
  * @param mon Monitor which should monitor the servers
- * @param monitored_servers_out Where to save output. The caller should free the array, but not the elements.
- * @return Output array size if successful, negative value otherwise
+ * @param monitored_servers_out Where to save output array. The caller should free the array, but not the
+ * elements. The output must contain NULL before calling this function.
+ * @return Output array size.
  */
 int mon_config_get_servers(const MXS_CONFIG_PARAMETER* params, const char* key, const MXS_MONITOR* mon,
                            MXS_MONITORED_SERVER*** monitored_array_out);
diff --git a/server/core/monitor.cc b/server/core/monitor.cc
index 67c97656a..113f56b80 100644
--- a/server/core/monitor.cc
+++ b/server/core/monitor.cc
@@ -2444,41 +2444,41 @@ MXS_MONITORED_SERVER* mon_get_monitored_server(const MXS_MONITOR* mon, SERVER* s
 int mon_config_get_servers(const MXS_CONFIG_PARAMETER* params, const char* key, const MXS_MONITOR* mon,
                            MXS_MONITORED_SERVER*** monitored_servers_out)
 {
-    ss_dassert(*monitored_servers_out == NULL);
+    ss_dassert(monitored_servers_out != NULL && *monitored_servers_out == NULL);
     SERVER** servers = NULL;
     int servers_size = config_get_server_list(params, key, &servers);
-    int rval = 0;
+    int found = 0;
     // All servers in the array must be monitored by the given monitor.
     if (servers_size > 0)
     {
         MXS_MONITORED_SERVER** monitored_array =
             (MXS_MONITORED_SERVER**)MXS_CALLOC(servers_size, sizeof(MXS_MONITORED_SERVER*));
-        bool error = false;
-        for (int i = 0; i < servers_size && !error; i++)
+        for (int i = 0; i < servers_size; i++)
         {
             MXS_MONITORED_SERVER* mon_serv = mon_get_monitored_server(mon, servers[i]);
             if (mon_serv != NULL)
             {
-                monitored_array[i] = mon_serv;
+                monitored_array[found++] = mon_serv;
             }
             else
             {
-                MXS_ERROR("Server '%s' is not monitored by monitor '%s'.", servers[i]->unique_name, mon->name);
-                error = true;
+                MXS_WARNING("Server '%s' is not monitored by monitor '%s'.",
+                            servers[i]->unique_name, mon->name);
             }
         }
         MXS_FREE(servers);
 
-        if (error)
+        ss_dassert(found <= servers_size);
+        if (found == 0)
         {
             MXS_FREE(monitored_array);
-            rval = -1;
+            monitored_array = NULL;
         }
-        else
+        else if (found < servers_size)
         {
-            *monitored_servers_out = monitored_array;
-            rval = servers_size;
+            monitored_array = (MXS_MONITORED_SERVER**)MXS_REALLOC(monitored_array, found);
         }
+        *monitored_servers_out = monitored_array;
     }
-    return rval;
-}
\ No newline at end of file
+    return found;
+}
diff --git a/server/modules/monitor/mariadbmon/mysql_mon.cc b/server/modules/monitor/mariadbmon/mysql_mon.cc
index 7a9554d1e..49b0512cf 100644
--- a/server/modules/monitor/mariadbmon/mysql_mon.cc
+++ b/server/modules/monitor/mariadbmon/mysql_mon.cc
@@ -1176,6 +1176,21 @@ static bool stop_monitor(MXS_MONITOR* mon)
     return actually_stopped;
 }
 
+static string monitored_servers_to_string(MXS_MONITORED_SERVER** array, size_t array_size)
+{
+    string rval;
+    if (array_size > 0)
+    {
+        const char* separator = "";
+        for (size_t i = 0; i < array_size; i++)
+        {
+            rval += separator;
+            rval += array[i]->server->unique_name;
+            separator = ",";
+        }
+    }
+    return rval;
+}
 /**
  * Daignostic interface
  *
@@ -1196,8 +1211,14 @@ static void diagnostics(DCB *dcb, const MXS_MONITOR *mon)
                "Enabled" : "Disabled");
     dcb_printf(dcb, "Detect stale master:    %s\n", (handle->detectStaleMaster == 1) ?
                "Enabled" : "Disabled");
-    dcb_printf(dcb, "\nServer information:\n-------------------\n\n");
+    if (handle->n_excluded > 0)
+    {
+        dcb_printf(dcb, "Non-promotable servers (failover): ");
+        dcb_printf(dcb, "%s\n",
+                   monitored_servers_to_string(handle->excluded_servers, handle->n_excluded).c_str());
+    }
 
+    dcb_printf(dcb, "\nServer information:\n-------------------\n\n");
     for (MXS_MONITORED_SERVER *db = mon->monitored_servers; db; db = db->next)
     {
         MySqlServerInfo *serv_info = get_server_info(handle, db);
@@ -1265,7 +1286,11 @@ static json_t* diagnostics_json(const MXS_MONITOR *mon)
     {
         json_object_set_new(rval, "script", json_string(handle->script));
     }
-
+    if (handle->n_excluded > 0)
+    {
+        string list = monitored_servers_to_string(handle->excluded_servers, handle->n_excluded);
+        json_object_set_new(rval, CN_NO_PROMOTE_SERVERS, json_string(list.c_str()));
+    }
     if (mon->monitored_servers)
     {
         json_t* arr = json_array();