[rt-users] sendmail error (exited with code 75) - RHEL6

[Thomas Sibley]

On 09/12/2012 07:05 AM, Raphaël Berlamont wrote:
> Issue still running, and I don't have an idea where to look at...
> 
> To refresh your memory : sometime, RT can't send any mail piped into
> sendmail binary. To make it working again, I have to restart apache. It
> work for a few minutes, then stop working again.

This is very strange, and it's especially strange that you're seeing
this under the prefork MPM.  I expected you used a threaded MPM and were
running into weird threading bugs.

> To make this bad behavior almost unnoticeable by the user, I've set a
> cron that restart apache every five minutes, but of course, this is not
> a final solution...
> 
> For now, I changed the "MailCommand" to "smtp", and it works. I hope
> there is no limitation using this method instead of "sendmailpipe".

Setting MailCommand to 'smtp' is dangerous, and will likely be removed
in the next major version of RT (4.2).  It can result in dropped mail if
the SMTP server isn't responding since RT isn't queueing mail like an
MTA does.