Bitwise Evolution

The mono project, which aims to provide an OSS alternative to the .Net framework, is capable of serving ASP.Net pages (amongst other things). On Friday I sat down to do this, and realized that while there are many pages that describe the process, none that I could find, covered all the info needed to actually get up and running. (I’ve built a Google Notebook of the better links I visited — look here for those.)

The Webserver

ASP.Net pages are served up by a web server called XSP (or XSP2). XSP is a stand alone web server, however it doesn’t have much of the functionality of Apache. XSP is great for testing, and would work well on a dev machine, but it’s not something you’d use directly for a live sever. Generally, you’ll want to run Apache with mod_mono, which is essentially a wrapper around XSP[2].

XSP vs. XSP2 — XSP2 is capable of serving up ASP.Net 2.0 pages, while XSP is only 1.1 capable.

Packages

I work under Ubuntu, but the packages needed should be fairly easy to translate to other distros: (I already had mono installed — that step was trivial apt-get install mono or something similar. If you don’t have mono running, do that first.)

• apache2
• apache2-common
• apache2-mpm-worker
• apache2-utils
• asp.net2-examples
• mono-xsp2
• mono-xsp2-base
• mono-apache-server2
• libapache2-mod-mono

Installing mod_mono will tell you to force-reload apache:

 $ sudo /etc/init.d/apache2 force-reload
 * Forcing reload of apache 2.0 web server... 
apache2: could not open document config file /etc/mono-server/mono-server-hosts.conf   [fail]

In Ubuntu, at least, the default mod_mono.conf is not setup for XSP2. If you see the failure above, then just pop open /etc/apache2/mods-enabled/mod_mono.conf and swap the commented lines to point to the correct mono-server directory. /etc/mono-server2/mono-server2-hosts.conf.

Configuration

(The Ubuntu documentation has the best description of this process I’ve found. Look here for their steps. I’ve included this section anyway because I still had difficulty connecting the problems I had with the solution posted on the Ubuntu page.)

I’ll assume you’ve been able to install and load the mod_mono module. From this point, we need to set the ASP handler, and define mono web applications. The first step is straightforward, at least if you’re familiar with Apache configuration:

 # Enable ASP in /usr/share/asp.net2-demos
 Alias /samples "/usr/share/asp.net2-demos"

      SetHandler mono

The second step is new to me — apparently mono needs an application root of some sort defined in addition to the handler configured above. Most pages suggest using the line:

 MonoApplications "/samples:/usr/share/asp.net2-demos/"

However, that caused ‘mod_mono’ to segfault continuously (the apache logs were horrible:

 Another mod-mono-server with the same arguments is already running
 Another mod-mono-server with the same arguments is already running
 [notice] child pid 7371 exit signal Segmentation fault (11)
 [notice] child pid 7372 exit signal Segmentation fault (11)
 [notice] child pid 7373 exit signal Segmentation fault (11)
 [notice] child pid 7374 exit signal Segmentation fault (11)
 ....
 # (about 1 / second)

It turns out that there is another way to accomplish the same thing. /etc/mono-server2/ can contain .webapp files which define essentially the same thing. The format for these files can be found in ‘man xsp2’:

       {appname}
       {virtual host for application}
       {port for application}
       {virtual directory in apache}
       {physical path to aspx files}
        is true by default -->
       {true|false}

For the asp.net2 samples, I used this webapp config:

       samples
       localhost
       80
       /samples
       /usr/share/asp.net2-demos

After that, starting up apache worked without error and pointing a browser at http://localhost/samples popped up the Mono-project ASP.Net sample page.