We've just upgraded a machine from 8.04 to 10.04 (yes, long over due) but since the upgrade apache2 will not start.
Nothing shows in the error logs, not in apache's error.log, no console output, nothing in syslog.
We've already narrowed it down to mod_ssl. If I disable mod_ssl (a2dismod ssl), apache starts fine. Re-enable the module and the problem returns.
While debugging, I've already tried using the ssl.conf.dpkg-dist clean configuration file to make sure the problem isn't with an incompatibility in our SSL-config, but this does not change anything.
edit: Update: I took the easy way out and switched to mod_gnutls, so it's no longer that big of a deal. Still curious as to what it may have been, so if you have a possible cause, please do post it.