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CentOS: Setup DNSBL with DNS (named)

Hi All,

I Have a VPS server running CentOS 6.5

Two of my domains a being email spammed, all of the source IP's are listed in DNSBL

Can someone help me configure my DNS server (named) to use DNSBL so it drops requests from these IP's?


Many thanks
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detox1978
Asked:
detox1978
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1 Solution
 
Daniel HelgenbergerCommented:
Hello,

you can only configure your MTA (eg. postfix) to use DNSBL. Your named (if you have it running on your server) has nothing to do with it (though it may be configured as a forwarder)

Postfix will lookup the entries (IP-addresses) in DNSBL by DNS resolves. It uses the name servers configured in /etc/hosts. The DNSBL will return a return code if you have a match and nothing if the IP is not listed. Please see: http://www.spamhaus.org/zen/
You can test it yourself:
$ dig +short 0.210.73.208.sbl.spamhaus.org
127.0.0.2

Open in new window

This IP is (by whois) part of Oversee.net, which has blacklisted this IP manually by submitting it to spamhaus. The return code tells you it is in the 'Directly added' list.
Another example, if your ISP is operating by the books:
$ dig +short 139.83.64.91.zen.spamhaus.org
127.0.0.11

Open in new window

This is the current IP of my router at home, my ISP (kabeldeutschland.de) has done a good thing by submitting it to spamhaus as
End-user Non-MTA IP addresses set by ISP outbound mail policy

This is practically the same thing postfix would do. If these simple tests result in these return codes, your entries in reject_rbl_client are working.

Kindly continue on your other thread:
http://www.experts-exchange.com/OS/Linux/Q_28383789.html
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SandyCommented:
Configure the postifx with DNSBL to avoid further block

TY/SA
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detox1978Author Commented:
Sorry I didnt relise DNSBL couldnt be used on DNS.  I was struggling to get it setup on postfix, so thought I'd try named in tandem.

I will go back to the postfix thread.

Thanks
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detox1978Author Commented:
I've requested that this question be deleted for the following reason:

DNSBL cant be setup with named.   So this question isnt needed.
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Daniel HelgenbergerCommented:
Hello detox1978.

IMHO this question should be closed or an accepted rather than deleted, since I consider even a negative ( = it is not possible) an answer, at least it helped you ruling out an approach.
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SandyCommented:
Agree
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detox1978Author Commented:
Sure no prob.
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