Re: [exim] Bad addresses in forwards

On Fri, 8 Jan 2016, Robert Blayzor wrote:

> What is the best way to handle/verify valid forwarding addresses from users.
>
> We have had a problem where old accounts with forwards in them just keep
> accepting email and then trying to deliver them to no longer existent
> remote email accounts.
>
> Is there a way/best practice to verify the forwarding address before
> accepting the message being delivered? This would allow us to reject it
> at SMTP time rather than letting thousands of messages queue up for
> delivery and then ultimately bounce.

There is recipient-verify callout/callforward (chapter 44 onwards).

I used to use callouts, but eventually gave up (I no longer have my notes
but the problem may have been *sender* verify callback).
Yours may be a case that is less problematic.

Looking at the manaul now there are many new options for callouts
since I used it in anger.

--
Dr. Andrew C. Aitchison