I promised you a horror story about Debian unstable. Here it is.
I was asked to fix a small web application on a remote server. The "deputy sysadmin" (a PC technician) wrote me something like this: «Our SSL certificates expired, so we renewed them and I had my boss re-enter the certificates. Since then we can get to the login page for XXX, but it comes up with a blank screen after you have authenticated. Can you look into that and see if you can fix it or give us some direction on what else we can troubleshoot?»
Wow. That server was an i386 PC with Debian Sid (unstable), kept up-to-date, which can be considered almost a production server: they can afford some downtime, but not that much.
Now, how on Earth could a SSL certificate break a LAMP application?
The issue was not related to the SSL certificate. The issue raised at some unknown point when the MySQL module for PHP became unavailable, due to the sad fact that the server was running Debian Sid, and not Lenny (if not Etch).
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