I think it is time to rebuild my server from scratch. But I don't want to have to rebuild the ISPConfig side of it. Would it be possible to back the entire system up, rebuild a debian perfect Server, then restore the relevant directories? I guess it would be /var/lib/mysql for the databases and /home and /root for ISPConfig and the websites. Or would that not work? Right now the system is not running properly: it seems to have lost the ability to run php on the production web server, though ISPConfig admin's php is fine.