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plesk 9.0 the source for backscatter!

105547111

Silver Pleskian
How many of you see emails from mailer daemon stuck in your mail queue?

How many are for some non existent dfgsdgd@ user at your domains? (this I can fix do the mod below)

After spending days and days, the postfix users have told me that its the way plesk is handling spam that is causing 'backscatter'.

Bouncing spam instead of deleting it. These bounces then get stuck in the outgoing mailserver queue as they are all spam and undeliverable.

This makes anyone using plesk a source of backscatter and that is really BAD you can get blacklisted for doing this.

This needs to be addressed ASAP. Its something in 9 the way it handles mail has changed since the other versions.

The issue is you don't bounce SPAM - ever.

So far I have minimised it by rejecting spam for users that are NOT on the server by editing /etc/postfix/main.cf:

# REJECTING MAIL FOR UNKNOWN LOCAL USERS
local_recipient_maps = $virtual_mailbox_maps

#smtpd_sender_restrictions = check_sender_access hash:/var/spool/postfix/plesk/blacklists
smtpd_sender_restrictions = check_sender_access hash:/var/spool/postfix/plesk/blacklists, reject_non_fqdn_sender, reject_unauthenticated_sender_login_mismatch

Thanks!

David
 
Thank you. I have implimented your suggestions and will watch to see what happens.
 
It helps, but as I said it wont stop it. But atleast now your not backscattering non existent addresses on your server, I cut back from 50 a day to about 4 to 6 :)

But we need a proper fix from plesk they should not be bouncing bloody spam!

Also now guess what, if you had a mailbox with no redirects or groups and mailbox, it now bloody sends a bounce email so now you cant blackhole email!

Stupid to say the least as if you create a mailbox and dont forward it anywhere it should not bounce!
 
Im sorry if this isnt terribly helpful - I dont use Plesk email becuase it has always sucked, but isnt there an option somewhere to black hole email delivered to non existant domains and addresses instead of bouncing?

Does this help?

Code:
letters sent to a nonexistent mailname, are bounced with this phrase
/usr/local/psa/admin/bin/mailmng --set-bounce --domain-name=<domain> --phrase=<phrase>

You could run it in a script against all your domains
Code:
mysql -Ns -uadmin -p`cat /etc/psa/.psa.shadow` -Dpsa -e  "select name from domains" > /tmp/list 
for domain in `cat /tmp/list` ; do 
/usr/local/psa/admin/bin/mailmng --set-bounce --domain-name=$domain --phrase=<phrase>
done

And then you can setup an event handler to do that to each new domain

Not sure if that really helps you at all
 
Hi,

In Plesk there are several options on what to do with mail to non-existent users:
# Continue returning all such mail back to senders (Bounce option),
# Forward all such mail to the specified e-mail address (Catch to address option),
# Forward all such mail to another mail server with the specified IP address (Redirect to external mail server with IP address option),
# Reject such mail without accepting it and without notifying senders (Discard option).

It is configured on per domain level:
http://download1.parallels.com/Plesk/PPP9/Doc/en-US/plesk-9.0-administrators-guide/toc58805234.htm

Generally recommended configuration is to reject such emails - this prevents excessive load on mail server.

You can change this setting for multiple domains at once by selecting domains on Domains page on clicking on 'Modify' button.
 
Hi,

In Plesk there are several options on what to do with mail to non-existent users:
# Continue returning all such mail back to senders (Bounce option),
# Forward all such mail to the specified e-mail address (Catch to address option),
# Forward all such mail to another mail server with the specified IP address (Redirect to external mail server with IP address option),
# Reject such mail without accepting it and without notifying senders (Discard option).

It is configured on per domain level:
http://download1.parallels.com/Plesk/PPP9/Doc/en-US/plesk-9.0-administrators-guide/toc58805234.htm

Generally recommended configuration is to reject such emails - this prevents excessive load on mail server.

You can change this setting for multiple domains at once by selecting domains on Domains page on clicking on 'Modify' button.


This is all correct... The problem is Plesk 9 is junk and fails to do what it is supposed to do. It does not work correctly.
 
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