Blocking large amount of spam domains

Rodrigo Gomes

Well-Known Member
Apr 6, 2016
126
29
28
Brazil
cPanel Access Level
Root Administrator
Hello,
I am using this suggestion below from a forum member on how to block spam domains.

Specifically this rule:
Imagine you are seeing a lot of Spam mails originating from a domain say example.com in your server logs. We can blacklist the domain example.com from sending mails through Exim mail server.

Create a file named /etc/eximblacklist and add the entry "example.com" (without quotes). That is, add the domains you need to blacklist one per line.

Now go to WHM >> Exim configuration editor >> Advanced Editor.

Add the below lines in the first section just below the line "#!!# cPanel Exim 4 Config"

domainlist exim_blacklist = /etc/eximblacklist

Now add inside the section under "ROUTERSTART"

reject_domains:

driver = redirect
# RBL Blacklist incoming hosts
domains = +exim_blacklist
allow_fail
data = :fail: Connection rejected: Host domain is banned

Save the configuration and see the exim error log. You can see the domain blocked.
But in my country we have received a very large amount of spam!
So much so that this list of domains currently has 2000 lines.

We have already used all other methods available in the cpanel against spam.
And we also block a large number of IP numbers.

My doubt is the following: this blacklist of domains will be a very heavy job for the server to process in each email?
 
Last edited:

Rodrigo Gomes

Well-Known Member
Apr 6, 2016
126
29
28
Brazil
cPanel Access Level
Root Administrator
Hello,
I don't feel so that will be a heavy job for the server to block those domains listed in eximblacklist file.. So don't worry about that, it should not affect your server performance.
Thank you webhostuk! The performance of a large list really worries me about using this method.

Hello,

You may also find the following thread helpful when seeking out additional solutions for blocking SPAM:

New anti-spam DNSBL in the works -- looking for testers

Thank you.
Hello Michael!

In fact I do not have spam issues with new domains "yet."
But I'll consider using it in the future if it turns out to be a problem. Thank you!

My problem is very specific: regional spam

In my country (Brazil) there are no RBLs for spam in our region.
And the international RBLs do not catch the majority of Brazilian spammers.

And the spammers here are very aggressive, they send a huge amount of traffic every day.
You see, I have a list of 2000 confirmed spam domains that I created myself. That in a few months!

The best way I found was to block domains, beyond the IP ranges.
 
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