EnvironmentError: The environment options "TRAC_ENV" or "TRAC_ENV_PARENT_DIR"
or the mod_python options "TracEnv" or "TracEnvParentDir" are missing.

Yuck. What’s more, if you’re using SuExec (like I am) then your Apache directives are ignored.

Solution: Edit your trac.fcgi and prepend the following code.

# hack for SuExec
import os;
os.environ['TRAC_ENV_PARENT_DIR'] = ‘/var/lib/trac’

But that’s impossible!!

HTTPS is just HTTP encapsulated inside an SSL tunnel. Apache’s virtual hosts are a clever “hack” whereby the Host header in the HTTP packet is verified. This alllows a single apache instance on a single IP/Port combination to serve a (not so) infinite number of differentes sites (aka vhosts).

Problem: The SSL tunnel is created before the first HTTP packet gets sent. Apache needs an SSL certificate but doesn’t have a Host header to match, hence cannot choose a virtual host.

Solution

This trick essentially does the matching of the Host header after the SSL connection has been established. How? Via some mod_rewrite magic!

Caveats

Although I said so, it’s not really that magical. There are a few things this trick does not solve.

• The SSL certificate used will be common to all SSL vhosts.
• Certain Apache directives may be common to all SSL vhosts (example: SuExecUserGroup). Basically anything you can’t override in a .htaccess file will be shared amongst vhosts.

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