Re: [SLUG] individual sender email verification on inbound

[Mary Gardiner <mary@xxxxxxxxxxxx>]

On Tue, Jul 29, 2008, Voytek Eymont wrote:
> is there any req on me having an 'apache@' address if I'm sending
> emails as such ?
> 
> (i.e., who misconfigured their server ?)

Sender address verification is a fairly common anti-spam technique.
RFC 2821 allows for mail to be rejected based on local policy, and the
remote end has chosen to implement a policy whereby the return address
must verifiably exist (in the sense of being able to receive the first
part of an SMTP transaction) before accepting mail. So it's not a
configuration that violates the protocol, that I can see.

Whether it's a totally sensible configuration is another question: it
tends to interact badly if the sender address in turn greylists incoming
mail, for example. But it's unlikely to be accidental on their part.

In general, send those mails out with a valid envelope-from address if
you don't want them to fall foul of people's spam filters or otherwise
annoy them, if, for example, one of the addresses is invalid and you
never find out about it because you keep handing it off to a relay and
letting the relay eat the bounce messages.

-Mary