Configuring sendmail to drop invalid users

[Matt Bullock]

Just a quick opinion regarding catch-all configurations - without one
set up, if someone misspells your name sending you an email, they would
get an almost immediate reply that the address doesn't exist.  With a
catch-all they would never get any notice that the email they sent
didn't arrive as planned.  I like the idea of not having a ton of bogus
return email sitting in the outbound queue, but I think it's a good
tradeoff so an accidental misspelling doesn't end up in limbo.


Regards,

Matt Bullock
Troika Networks, Inc.
Network Administrator
805.367.2728

-----Original Message-----
From: MailScanner mailing list [mailto:MAILSCANNER at JISCMAIL.AC.UK] On
Behalf Of kfliong
Sent: Tuesday, September 28, 2004 1:17 AM
To: MAILSCANNER at JISCMAIL.AC.UK
Subject: Configuring sendmail to drop invalid users

Hi all,

As you know, i was having "joe-job" attack yesterday. I have since fixed
it by adding the script provided by Steve to sendmail.cf file.

I now want to refine script by allowing only mails sent to valid users.
Those mails send to invalid users currently goes to catchall account.
And I have configured catchall to go to /dev/null. But this is not good
enough as these mails are still keep in queues and then processed by
mailscanner. Is there a way to drop these mails directly from MTA level?

I have looked in the link in mailscanner.info that teaches how to check
for valid users but that uses windows active directory users. I am using
ensim pro on the same box with sendmail. Any solution to this?

Thanks in advance.

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