Properly Reject Invalid Email Exim
Tired
of seeing your mail queue fill up with bounce messages to non-existant
spammer email addresses? By default, if an email comes into your server
addressed to an invalid recipient, Exim will accept the message from
the delivering agent, and then generate a return email to them
explaining that the address is invalid. With this little tweak, you can
make exim tell the delivering agent that that address is invalid at the
time the message is being delivered, meaning no more spam returns
cluttering up your queue! Can I get an Amen!? Read on!
This is curtesy of cyberspirit in the cpanel forums. Original thread is loacted here.
Method 1)
1. Open WHM and click on Exim Configuration Editor
2. Click on the Switch to Advanced Mode button.
3.
Scroll down until you see the section on ACL's. You'll see three boxes.
In the middle box, locate the section that reads - See Section A:
Method 2) Recommended
1. Login into SSH and su to root
2. pico /etc/exim.conf
3. Ctrl + W and type in: accept domains Notice the two spaces. Look for something like this below.
Section A:
accept domains = +local_domains
accept domains = +relay_domains
accept hosts = +relay_hosts
accept condition = ${perl{checkrelayhost}{$sender_host_address}}
Between
accept domains = +local_domains
and
accept domains = +relay_domains
add the following:
endpass
message = unknown user
verify = recipient
Make sure each line lines up. You might need to add two spaces before each line. The final section will look like this:
accept domains = +local_domains
endpass
message = unknown user
verify = recipient
accept domains = +relay_domains
accept hosts = +relay_hosts
accept condition = ${perl{checkrelayhost}{$sender_host_address}}
Scroll all the way to the bottom and click on Save.
That's it! Welcome to much smaller mail queues!
