Hi,
Thanks for the response. Two questions:
1) Which variable in main.cf should this lookup table be referenced in?
2) I've read the man page, but it isn't clear in whether I can
reference a database or table which is produced as the output of a
program? For example, whether postfix can read the output of some kind
of generatetable.pl file?
Cheers!
On 26 Sep 2008, at 11:44, Wietse Venema wrote:
Alan Boyd:
Hello,
I'm trying to find a way to reject email which is sent to an unknown
user (determined by an external program) at a virtual domain, such
that the email doesn't even enter the mail queue.
Currently, my set up is as follows:
I use a virtual mapping to send email in the format
[EMAIL PROTECTED] to a localuser.
In my aliases file, email to localuser is piped to an external
program
for delivery.
I can set up my external program to return a sysexit code of 67 so
that a bounce message is sent back to the sender. But since I'm using
a catchall email address, this would result in a very large number of
bounce messages being sent due to the spammer 'shotgun' approach of
trying to find valid addresses. I'd much prefer it if I can find a
way
to query the address early on so that an email to an unknown user is
rejected and doesn't even get in to the mail queue.
Any clues on how this might be accomplished? I can change my external
program as desired and the 'valid' email addresses are variable (and
fairly large) but known.
For Postfix to reject invalid recipients at the SMTP port, this
information must be available as a lookup table. You will have
to use one of the supported database types: file, SQL, LDAP, and
so on, or add your own table lookup mechanism.
See "man 1 postconf", option "-m".
Wietse
