backscatter with email Domain Alias

Hi, I know I've read about this sometime ago but can't find the topic anywhere.

I have a small issue,
In latest ispconfig I setup a domain and some mailboxes.
Then add an alias domain.

The problem is, that if I telnet to server port 25 and try to send an email to inexistent account, using the domain of the account the mail isn't accepted by the mailserver, but if I use the virtual domain, email gets accepted, and later generating a bounce email.
This is giving me some headache with several backscatter emails.

Is there a workaround for this?

mysql-virtual_forwardings.cf

Code:

user = ispconfig
password = *******************
dbname = dbispconfig
table = mail_forwarding
select_field = destination
where_field = source
additional_conditions = and active = 'y' and server_id = 1
hosts = 127.0.0.1

 

Hello Till,
I have read this old post because we he have the same problem.
In your actual forwarding.cf you have deactivated the aliasdomain type filter. In this case the mailserver can be used as backscatter server. I try to activate the type filter so no mail for the alias domains will be accepted.

Now I have created my own mysql table mappings. First I have changed forwarding.cf for ignoring aliasdomains but handle catchall purposes. Than l have created another map for testing the existence of the mailbox in the destination domain. I have linked the maps in the main.cf and also added the reject unknown clients in the client restrictions.
For the postfix I can’t find a template. I only found a php script. What about updates? How can I save for updates with this custom settings? For my MySQL maps I’ve used new files, but what about the main.cf?

Greetings Sven