[CentOS] Apache wakes-up inactive Exim

Sun Sep 28 20:03:40 UTC 2014
Александр Кириллов <nevis2us at infoline.su>

> I was remotely testing a web page. A web page error condition invoked
> the embedded PHP mail() command.
> 
> To my astonishment something in Centos woke-up Exim. Exim sent the 
> email
> and then became inactive again. The Exim logs does not show any 
> start-up
> lines, just
> 
> 1. input from Apache.
> 2. output to remote server.
> 3. 'completed'.
> 
> Hours later Logwatch, not yet customised, also caused inactive Exim to
> send an email (which got rejected by Exim because it was to local user
> 0).
> 
> What causes Centos to temporarily activate in-active (meaning
> non-running) Exim ?

You don't really need an active smtp daemon to send email or deliver it 
locally.
$ cat /etc/php.ini | grep sendmail