Mod_Mono & Apache: Failed to create shared memory segment for backend

Question

Hi

I have successfully installed mod_mono 2.4 and httpd on Fedora 11 and got httpd to start.

But when I add:

<VirtualHost XXX.XXX.XXX.XXX:80>
  ServerName mydomain.com
  ServerAlias www.mydomain.com
  ServerAdmin [email protected]
  DocumentRoot /usr/lib64/xsp/test/

  MonoServerPath mydomain.com "/usr/lib64/mono/2.0/mod-mono-server2.exe"

  # To obtain line numbers in stack traces you need to do two things: 
  # 1) Enable Debug code generation in your page by using the Debug="true" 
  #    page directive, or by setting <compilation debug="true" /> in the 
  #    application's Web.config
  # 2) Uncomment the MonoDebug true directive below to enable mod_mono debugging
  MonoDebug mydomain.com true

  # The MONO_IOMAP environment variable can be configured to provide 
  # platform abstraction
  # for file access in Linux.  Valid values for MONO_IOMAP are:
  #    case
  #    drive
  #    all
  # Uncomment the line below to alter file access behavior for the 
  # configured application
  MonoSetEnv mydomain.com MONO_IOMAP=all

  MonoApplications mydomain.com "/:/usr/lib64/xsp/test/"
  <Location "/">
    Allow from all
    Order allow,deny
    MonoSetServerAlias mydomain.com
    SetHandler mono
  </Location>
</VirtualHost>

And then try to restart:

# sudo service restart http

I get this error:

Starting httpd: [Fri Jun 12 06:43:18 2009] [crit] (17)File exists: Failed to create
shared memory segment for backend 'XXGLOBAL' at '/var/run/mod_mono
/mod_mono_dashboard_XXGLOBAL_1'.

Please help!

Thanks.

Answer 1

There is a know issue with using "restart" with Apache2 and mod_mono. The Mono website recommends using "reload" with Apache2 instead. From what I can tell they're blaming it on a bug in Apache2 (pure speculation on my part though).

Either way, it isn't actually a critical issue. I've been running an ASP.NET site on Mono for over a year now, and even though I always get that error on restart, I've never actually experienced any side effects from it.