Odesílání POST na jinou doménu

Header Set Access-Control-Allow-Origin "https://domena1"

    $.ajax({
        type: 'POST',
        url: 'https://domena2/save-question.php',
        crossDomain: true,
        data: '{"some":"json"}',
        dataType: 'json',
        success: function(responseData, textStatus, jqXHR) {
            var value = responseData.someKey;
        },
        error: function (responseData, textStatus, errorThrown) {
            alert('POST failed.');
        }
    });