Change DIV background image randomly at regular interval in JavaScript

<div id="main_header_image">
    header
</div>
<div id="main_header_image1">
    header 1
</div>
<div id="main_header_image2">
    header 2
</div>
<script type="text/javascript">
    window.onload = function () {
        document.getElementById('main_header_image').style.backgroundImage = "url('https://static.flickr.com/72/199481203_ad4cdcf109_s.jpg')";
        var rndImages = [
                "https://static.flickr.com/66/199481236_dc98b5abb3_s.jpg",
                "https://static.flickr.com/75/199481072_b4a0d09597_s.jpg",
                "https://static.flickr.com/57/199481087_33ae73a8de_s.jpg",
                "https://static.flickr.com/77/199481108_4359e6b971_s.jpg",
                "https://static.flickr.com/58/199481143_3c148d9dd3_s.jpg",
                "https://static.flickr.com/72/199481203_ad4cdcf109_s.jpg",
                "https://static.flickr.com/58/199481218_264ce20da0_s.jpg",
                "https://static.flickr.com/69/199481255_fdfe885f87_s.jpg",
                "https://static.flickr.com/60/199480111_87d4cb3e38_s.jpg",
                "https://static.flickr.com/70/229228324_08223b70fa_s.jpg"];

        setInterval(function () {
            var i = Math.floor((Math.random() * rndImages.length));
            document.getElementById('main_header_image').style.backgroundImage = "url('" + rndImages[i] + "')";
        }, 2000); // Change 2000 to 10000.
    }
</script>