Backend: Set name if create default backend

fixes #7043

modules/monitoring/library/Monitoring/Backend.php

@@ -74,6 +74,9 @@ class Backend implements Selectable, Queryable, ConnectionInterface
         foreach (IcingaConfig::module('monitoring', 'backends') as $name => $config) {
             if (!(bool) $config->get('disabled', false) && $defaultBackend === null) {
                 $defaultBackend = $config;
+                if ($backendName === null) {
+                    $backendName = $name;
+                }
             }
             $allBackends[$name] = $config;
         }

modules/monitoring/test/php/regression/Bug7043Test.php

@@ -0,0 +1,31 @@
+<?php
+
+namespace Tests\Icinga\Module\Monitoring\Regression;
+
+use Icinga\Data\ResourceFactory;
+use Icinga\Module\Monitoring\Backend;
+use Icinga\Test\BaseTestCase;
+
+class Bug7043 extends BaseTestCase
+{
+    public function testBackendDefaultName()
+    {
+        $config = new \Zend_Config(array(
+            'ido' => array(
+                'type' => 'db',
+                'db'        => 'mysql',
+                'host'      => 'localhost',
+                'port'      => '3306',
+                'password'  => 'icinga',
+                'username'  => 'icinga',
+                'dbname'    => 'icinga'
+            )
+        ));
+
+        ResourceFactory::setConfig($config);
+
+        $defaultBackend = Backend::createBackend();
+
+        $this->assertNotNull($defaultBackend->getName(), 'Default backend has a name property set');
+    }
+}