2. What you need to run OpenACS

- AOLserver - A free, Tcl-enabled, multi threaded, powerful web server that is behind huge sites such as aol.com and digitalcity.com. AOLserver is also a complete web development platform being designed from start to have efficient access to databases. We support AOLserver 3. NOTE: In february a fork of the AOLserver project was started to better address user contributions and requests. The project is called OpenNSD and its home page is at http://www.opennsd.org)

(Note: ArsDigita and Robert Thau came up with a mod_aolserver for the Apache web server, which intends to replicate the AOLserver API on Apache. It has performance issues when compared to AOLserver, but Apache fans can use it. http://apache.arsdigita-dev.com)

- PostgreSQL - A free, powerful SQL92-based Relational Database Management System with advanced features including Multi-variant Concurrency Control (unlike in the more common table-locking model, readers don't wait for writers and writers don't wait for readers, very crucial in a high-volume web server environment). Version 7 is the supported version.

- Some flavor of UNIX or Windows. Our development is almost entirely done on GNU/Linux (and when not done in GNU/Linux, it is tested on it) and for now, this is the only operating system we can help you with. Some very big web sites run on GNU/Linux and it has proven itself as a great platform for web servers, plus it is free software. Red Hat Linux and Debian GNU/Linux are the reference distributions for AOLserver and OpenACS, but if you know what you are doing, you can use any GNU/Linux distribution (and many people do).

In fact, Debian GNU/Linux has OpenACS .deb packages all ready to install. Thanks to Brent Fulgham for providing the Debian packages. ArsDigita is providing RPM packages for OpenACS with mod_aolserver on Apache. They are available at the OpenACS software page.

To get OpenACS working on Windows you will have to get PostgreSQL working on it first, which is beyond the scope of this document. Please refer to the PostgreSQL documentation for that information. The OpenACS-specific instructions should need very little adaptation. Please contribute the documentation for Windows if you are going to do it.

- The PostgreSQL driver for AOLserver, available at OpenACS software page..

- The OpenACS distribution, available at OpenACS software page..