[pve-devel] [PATCH v4 many 00/11] notifications: add SMTP endpoint

[Dietmar Maurer]

> On 11/8/23 16:52, Dietmar Maurer wrote:
> >> This patch series adds support for a new notification endpoint type,
> >> smtp. As the name suggests, this new endpoint allows PVE to talk
> >> to SMTP server directly, without using the system's MTA (postfix).
> > 
> > Isn't this totally unreliable? What if the server responds with a
> > temporary error code? (An MTA retries several times).
> 
> The notification system has no mechanism yet for queuing/retries,
> so yes, at the moment a SMTP endpoint would indeed be less reliable than 
> a 'sendmail' endpoint. I'm not sure though if I would call it
> 'totally unreliable'.

This kind of notification system is quite popular for (PHP) web-sites contact 
form. I have seen many over-simplified implementation overs the years,
and yes, it is totally unreliable.

That is why we always used an MTA to deliver mails...