core-bundle/src/Resources/contao/models/PageModel.php
public static function findPublishedFallbackByHostname($strHost, array $arrOptions=array())
	{
		// Try to load from the registry (see #8544)
		if (empty($arrOptions))
		{
			$objModel = Registry::getInstance()->fetch(static::$strTable, $strHost, 'contao.dns-fallback');

			if ($objModel !== null)
			{
				return $objModel;
			}
		}

		$t = static::$strTable;
		$arrColumns = array("$t.dns=? AND $t.fallback='1'");

		if (!static::isPreviewMode($arrOptions))
		{
			$time = Date::floorToMinute();
			$arrColumns[] = "($t.start='' OR $t.start<='$time') AND ($t.stop='' OR $t.stop>'" . ($time + 60) . "') AND $t.published='1'";
		}

		return static::findOneBy($arrColumns, $strHost, $arrOptions);
	}
public static function findPublishedFallbackByHostname($strHost, array $arrOptions=array())
	{
		// Try to load from the registry (see #8544)
		if (empty($arrOptions))
		{
			$objModel = Registry::getInstance()->fetch(static::$strTable, $strHost, 'contao.dns-fallback');

			if ($objModel !== null)
			{
				return $objModel;
			}
		}

		$t = static::$strTable;
		$arrColumns = array("$t.dns=? AND $t.fallback='1'");

		if (!static::isPreviewMode($arrOptions))
		{
			$time = Date::floorToMinute();
			$arrColumns[] = "($t.start='' OR $t.start<='$time') AND ($t.stop='' OR $t.stop>'" . ($time + 60) . "') AND $t.published='1'";
		}

		return static::findOneBy($arrColumns, $strHost, $arrOptions);
	}
Find the language fallback page by hostname

@param string $strHost    The hostname
@param array  $arrOptions An optional options array

@return PageModel|Model|null The model or null if there is not fallback page