I don’t think DH’s Apache config is documented publically anywhere, although it would be helpful at times.
For help setting up Apache VirtualHosts, see the documentation.
If you want CGI to run as you rather than the Apache user, you’ll need to use suEXEC. The only reason you’ll need this is if you need to write to the filesystem, and you can do this a whole lot easier by just making the necessary files/directories writable by the Apache user on your development setup. If it works in this configuration at home, it will work under suexec on the DH server.
That’s really about it. I do my development using the stock Apache 1.3 that comes with OS X, with only the addition of PHP5 and FastCGI. I don’t even bother using PHP-CGI at home; code written for a non-restricted mod_php environment (unlike the one at DH) will usually run under CGI just fine (I have yet to see anything break, anyway).
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