Re: How would you provide a 554 rejection notice for spam?

Rick Macdougall wrote:
>
> simscan correctly uses an SMTP REJECT (55x code during the smtp
> conversation) and it is also possible to use custom reject messages
> with simscan so the sender, if any, knows exactly why the message was
> rejected.
>
> I have yet to see a good implementation of this in Postfix or
> Sendmail, and is one of the reasons I stick with Qmail.

running SA at smtp time requires that the client does not timeout. so you'd better scan fast! you're also more subject to DOS (your smtp listeners are busy). compare this to queue and filter...

anyway, you can still do smtp time filtering with postfix and sendmail. google for milter and proxy_filter.

>
> Having to /dev/null spam and/or viruses to the end user is even worse
> IMHO (as an ISP, it might be acceptable in an office env where you can
> train the users to look at spam or virus folders).

Reject (not bounce) is acceptable, but you'd better configure your filter correctly. If I get a reject from you for a legitimate mail I sent, you will just make yourself ridiculous... It also delays legitimate mail (because I have to resend).

delivering to a Junk folder and letting the recipient review this folder maybe annoying, but if the recipient is not too dumb (or too busy), then he can "save ham transparently".

anyway, each site has its own policy for handling spam. What we ask is to avoid bad practices that result in annoying others (backscatter, C/R, ... etc). The rest (discard, reject at smtp time, quarantine, ...) is up to you, your boss, your users, your customers, ... etc. Received on Tue Jul 31 17:38:40 2007