Update:  I've found and documented an ugly hack that works around the problem:

http://vufind.org/wiki/vufind2:installing_multiple_instances#apache_configuration_for_directory-based_multisite

(This involves creating a symbolic link to VuFind's public directory for each instance, and then editing the Apache configurations so that each instance has its own unique <Directory> configuration).

It works, but it's extremely inelegant!  If anybody knows of a better, configuration-driven way of solving this problem, please let me know.

- Demian

From: Demian Katz
Sent: Friday, September 28, 2012 12:58 PM
To: vufind-tech@lists.sourceforge.net
Subject: VF2 multiple configurations: need Apache expert advice

I've been testing and documenting VuFind 2.0's multisite capabilities -- the fact that you can set up multiple configurations for a single instance of VuFind -- and am running into some unexpected problems.

There are ideally two ways to do this -- host-based (site1.vufind.org, site2.vufind.org, etc.) or directory-based configuration (vufind.org/site1, vufind.org/site2, etc.).

I thought the host-based configuration would be the hard part, but that seems to work quite nicely.

I'm having trouble with the directory-based configuration, however.  It appears that if you load multiple instances of VuFind's default httpd-vufind.conf file, the RewriteBase directives conflict with one another, and only the last-loaded configuration works properly.  I've been banging my head against this all day and can't find a good solution.  It probably requires reinventing the mod_rewrite configuration.  I don't want to make the default configuration incredibly complicated just to satisfy this one edge case.

Any brilliant ideas?  You can learn more about the current state of the art here:

http://vufind.org/wiki/vufind2:installing_multiple_instances

thanks,
Demian