How to Display Server Uptime with ASP and ASP.NET

Learn how to display the server's uptime using a mix of ASP Classic, ASP.NET and AJAX

Posted by Hüseyin Sekmenoğlu on June 02, 2013 Backend Development

📝 Introduction

Sometimes you want to display how long your web server has been running. In the early days, you might think of launching a background process at system startup to record the time and then calculate the difference in your ASP code. But there is a more elegant and dynamic solution using ASP.NET and AJAX together. This article explains both approaches and shows you how to implement a modern version.

🧪 The Old-School Approach

Before diving into ASP.NET, let’s look at the original workaround used to calculate server uptime:

  1. A small executable runs once at system startup.

  2. This app writes the current date and time to a file and exits.

  3. The ASP page reads that file.

  4. It subtracts the recorded startup time from the current time and displays the difference.

Although functional, this method requires file system access and startup configuration, which may not be ideal in all hosting environments.

🚀 A Smarter Way Using ASP.NET and AJAX

You can leverage the power of the System.Diagnostics namespace in ASP.NET to get the server's uptime directly using a performance counter. Then, you can display this information inside your classic ASP page using AJAX.

🛠️ Step 1: Create an ASPX Page (uptime.aspx)

Save the following code as uptime.aspx in your web directory:

<%@ Page Language="C#" %>
<%@ Import Namespace="System.Diagnostics" %>

<script runat="server">
    protected void Page_Load(object sender, EventArgs e)
    {
        PerformanceCounter pc = new PerformanceCounter("System", "System Up Time");
        pc.NextValue(); // discard the first value
        TimeSpan ts = TimeSpan.FromSeconds(pc.NextValue());

        Response.Write($"This system {Environment.MachineName} has been up for {ts.Days} days {ts.Hours} hours {ts.Minutes} minutes and {ts.Seconds} seconds.");
    }
</script>

This page returns plain text indicating how long the server has been running.

🧩 Step 2: Create the Classic ASP Page

Here is how to fetch and display the uptime from your uptime.aspx file using AJAX inside a classic ASP file.

<div id="result"></div>

<script>
    GetUptime();

    function GetUptime() {
        var xmlHttp = GetXmlHttpObject();
        if (xmlHttp == null) return;

        xmlHttp.onreadystatechange = stateChangedForUptime;
        xmlHttp.open("GET", "uptime.aspx", true);
        xmlHttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded; charset=iso-8859-1");
        xmlHttp.send(null);
    }

    function stateChangedForUptime() {
        if (xmlHttp.readyState === 4 || xmlHttp.readyState === "complete") {
            document.getElementById("result").innerHTML = xmlHttp.responseText;
        }
    }

    function GetXmlHttpObject() {
        var objXMLHttp = null;
        if (window.XMLHttpRequest) {
            objXMLHttp = new XMLHttpRequest();
        } else if (window.ActiveXObject) {
            objXMLHttp = new ActiveXObject("Microsoft.XMLHTTP");
        }
        return objXMLHttp;
    }
</script>

When the ASP page loads, it automatically calls GetUptime() which sends an AJAX request to uptime.aspx. The response is then displayed in the result container. This is a lightweight and interactive way to show real-time server uptime.

🧠 Summary

  • The old method relies on a startup log file to calculate uptime.

  • The improved method uses System.Diagnostics.PerformanceCounter in an ASPX file.

  • You can use AJAX in classic ASP to fetch and display the uptime.

  • This method works well even if your site is a mix of ASP and ASP.NET.

✅ Tips

  • Ensure uptime.aspx is deployed to a location accessible by your ASP pages.

  • AJAX is a better choice than iframes due to its flexibility and control.

  • This technique avoids the need for file I/O or additional programs at system startup.