Using sendmail, I am trying to setup a catchall address to silently discard spam mail sent to undefined users. I don't want to bounce a reply for "no user" as this often goes back to munged or innocent addresses.

I have a number of domains, so my virtuser table currently looks rather like this:

The last line is the "catchall" which is intended to ensure that any undefined users from either my_domain.com or my_domain.co.uk is forwarded to the non-existent "catchall" user account. Note that all mail sent to my_domain.com is passed across to my_domain.co.uk at the very start so all the following rules should apply to messages received at both domains. (Both of these domains appear in the

Being non-existent, I setup the following rules in the access data table:

This way, if I send an email to 'user1@my_domain.com' it is received and delivered to user1@my_domain.co.uk, but if I send an email to 'rubbish@my_domain.com' it *should* be received and silently discarded.

Unfortunately what actually happens is the server responds with:

Final-Recipient: rfc822; rubbish@my_domain.com
Action: failed
Status: 5.0.0
Diagnostic-Code: X-Postfix; host pbx.check-flight.com[xx.xx.xxx.xx] said: 550
5.1.1 <rubbish@my_domain.com>... User unknown (in reply to RCPT TO
command)

Now, (just for testing), I made "catchall" an alias for the "postmaster" account and the mail was then received and delivered into the postmaster mailbox. So I know the virtuser rule is working. The account "catchall", however, is not being silently dropped as desired in either configuration.

Anybody have any ideas how to make this work as intended?

Thanks.

Andy Woolford

Hi,

Remove the entry from accessdb and create an alias in /etc/mail/aliases
Don't forget to run:
afterwards

Thanks for this Bathory. You seem to be my guardian angel :-)

Unfortunately this didn't work. I get:

550 5.1.1 dev/null... User unknown

Are you sure you didn't missed the initial / in /dev/null
What gives
sendmail -bv catchall

Oops. My mistake. I forgot the leading /.

I now get: /dev/null... deliverable: mailer *file*, user /dev/null

...in response to the code you gave above.

/dev/null works fine when emailing now. Thanks again!

BTW, I use webmin to administrate most of these settings which gives a GUI interface to sendmail. It runs the necessary "assemblers" after the file is edited.

It begs a question though, (which probably underscores my lack of understanding), if all mail is written to this file /dev/null, won't this dump everything to disk, or is /dev/null a dummy file?

It's a special file, like a black hole. Everything written to it, it actually disappears. For more info have a look here

Regards

Just the job. Thanks :-)