Various Questions

[Somebody1]

Warning, lots of questions ahead!

I'm using CloudLinux 6.5 with Plesk Panel 12. I searched briefly to answer these questions myself, but dind't find any satisfactory answers.

1. Plesk uses fcgi for PHP-processing by default. How safe is this against the shell-shock bug?
   For those not knowing: The shell-shock is the misuse of environment variables. When including them in web-request, you can get a CGI-processor to execute your code. Very dangerous.
2. Where do I disable the sending of ETags in the HTTP Host headers?
3. How do I filter other headers? The Plesk version of NGINX does not seem to be compiled with the more_headers module...
4. My mail is hosted on a different server, so I disabled Plesk's mail functionality. I configured roundcube (/usr/share/psa-roundcube) to use that server, and it works. But to make it work, I needed to edit the template file to include ServerName webmail. Is it possible to enable this on the control panel? See attached screenshot. (Within Custom View Settings > Mail)
5. Is it possible to let external things (like a cache server) add the consumed bandwith/diskspace totals count?

If I have more questions, I will add them later.

Edit: Another question.

Thanks!