As I already told before, I love the Mono project. It enables to run the powerful Microsoft .Net Framework on UNIX/Linux/BSD systems.

I recently wanted to test a very cool feature of ASP.Net on a mono server. So I did a little

apt-get install lighttpd mono-fastcgi-server2 -y

The feature I wanted to try was a web scripting method ( with the [WebMethod] attribute) exporting some JSON directly from your method return value.

Here is the web scripting method declaration :

public partial class _Default:Page {
    [ScriptMethod( ResponseFormat = ResponseFormat.Json, UseHttpGet = false )]
    public static String TestMethod() {
        return DateTime.Now.ToString();

And here is the javascript / JQuery code that gets the data :

<div id="toto"></div>
<script type="text/javascript">
    function doIt() {
        $(document).ready(function() {
                type: "POST",
                url: "/Default.aspx/TestMethod",
                contentType: "application/json; charset=utf-8",
                data: "{}",
                dataType: "json",
                success: AjaxSucceeded,
                error: AjaxFailed
        function AjaxSucceeded(result) {
            document.getElementById("toto").innerHTML = result.d;
        function AjaxFailed(result) {
           document.getElementById("toto").innerHTML = "Error : "+result.status + ' ' + result.statusText;
        setTimeout("doIt()", 1000);

In my /etc/lighttpd/conf-enabled/10-fastcgi.conf file, I had this :

server.modules   += ( "mod_fastcgi" )
fastcgi.server    = (
        "" => ((
                "socket" => mono_shared_dir + "fastcgi-mono-server",
                "bin-path" => mono_fastcgi_server,
                "bin-environment" => (
                        "PATH" => "/bin:/usr/bin:" + mono_dir + "bin",
                        "LD_LIBRARY_PATH" => mono_dir + "lib:",
                        "MONO_SHARED_DIR" => mono_shared_dir,
                        "MONO_FCGI_LOGLEVELS" => "Standard",
                        "MONO_FCGI_LOGFILE" => "/var/log/lighttpd/mono.log",
                        "MONO_FCGI_ROOT" => mono_fcgi_root,
                        "MONO_FCGI_APPLICATIONS" => mono_fcgi_applications
                "max-procs" => 1,
                "check-local" => "disable"

Everytime I launched a call from javascript, I got (with JS) I got a “405 Method not allowed”. Well, that was pretty disturbing. Mostly because a google search on this didn’t give me anything.

My first thought was that mono didn’t react the same way the .Net framework does. But this isn’t it. It came from my crappy lighttpd config file. It didn’t search for the Default.aspx file but for the Default.aspx/TesMethod.

What you need to do is set :

fastcgi.server    = (
        ".aspx" => ((
            # Everything you have in your file (like my file above)
        ) = (
        ".asmx"   => ".aspx",
        ".ashx"   => ".aspx",
        ".asax"   => ".aspx",
        ".ascx"   => ".aspx",
        ".soap"   => ".aspx",
        ".rem"    => ".aspx",
        ".axd"    => ".aspx",
        ".cs"     => ".aspx",
        ".config" => ".aspx",
        ".dll"    => ".aspx"

And that will even improve your performances because any other file will be handled directly by lighttpd.

One quick note : There’s something weird with VS2008 WebDev.WebServer.Exe, the WebMethod request takes at least 1.0s to complete. On the same host with XSP, it’s around 15 ms. And on the Celeron 2.6Ghz linux server with lighttpd it’s around 12 ms. And on a IIS 7 server (bundled with Windows 7), it takes 12 ms. So why is the Visual Studio’s WebDev.WebServer so slow ?

By the way, why should we use a Linux + lighttpd + Mono server when we can use a Windows + IIS + ASP.Net server ? The reason is mainly that for the same usage, Linux consumes less resources and it’s easier to customize to suit your needs.

An other question you might have : Why use JQuery + JSON when you can use everything in the Microsoft AJAX Framework ? The main reason is that I really have the feeling to lose control with Microsoft AJAX Framework, I don’t like the huge automatically generated code. And it doesn’t make really fast web interfaces. With JQuery, everything goes faster and it’s way simpler to understand (and debug).

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