hostReachable.js

if (typeof networkTest === 'undefined') {
    var networkTest = {};

    (function() {
        this.hostReachable = function() {
            // Since we are setting the cache ajax option to false, we can take out the Math.random mechanism
            let url = '//' + window.location.hostname;
            let status;
            
            $.ajax({
                type: 'HEAD',
                async: false,
                cache: false,
                url: url
            }).done(function(data, textStatus, jqXHR) {
                status = jqXHR.status;
            }).fail(function(jqXHR, textStatus, errorThrown) {
                status = jqXHR.status;
            });
            
            if(status >= 200 && status < 300 || status === 304) {
                return true;
            } else {
                return false;
            }
        }

    }).call(networkTest);
}

wrote an equivalent function using jQuery ajax