Re: Open Proxy - how do I prevent it? (long mail)

From: Thomas Rokamp (
Date: 04/04/03

From: Thomas Rokamp <>
Date: Fri, 04 Apr 2003 15:42:38 +0200

> At a guess, your smtp server is probably accepting mail from and to any
>address on the net - i.e. it's probably acting as a relay usable by
>spammers. Unless you have a good reason to be offering an SMTP service to
>the world at large, you should probably block port 25; if OTOH you're
>running your own MX there should be some way to configure qmail to only
>accept mail destined for your domain.

I am running my own MX, so blocking the port wouldn't help me much.
I have tried setting up Qmail to only accept mail from local hosts,
but I might have misconfigured something.

Do you know any program or web page, that offers to test whether or
not a site "offers" an open STMP relay?

Thomas Rokamp

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