[SOLVED] DNSBL wrong detection

[hoanv9]

Hi all,
I am newbie with Proxmox mailgw. I used the DNSBL in setting with zen.spamhaus.org, threshold 1.
But i found that lots of messages were rejected, such as bellow but in spamhaus it clean ip

RCPT from [192.174.81.114]:34373: 550 5.7.1 Service unavailable; client [192.174.81.114] blocked using zen.spamhaus.org

 

[Stoiko Ivanov]

But i found that lots of messages were rejected, such as bellow but in spamhaus it clean ip

hmm - that usually means that the IP was listed when it tried to send mail to you - or that your dns-setup has an issue.

try querying for the ips from your PMG using dig/drill (you might need to install the 'dnsutils' or 'ldnsutils' packages) - see
https://www.spamhaus.org/faq/section/DNSBL Usage

I hope this helps!

 

[hoanv9]

I found that if the DNS is 8.8.8.8, many wrong spam detection. Once changed to OpenDNS, the issue was resolved.

 

[Stoiko Ivanov]

Glad you found the issue (although usually 8.8.8.8 does not give wrong answers (but some DNSBL are rate-limited and this usually means 8.8.8.8 is over limit - however then it still does not lead to a false positive, but to no blocking/hit at all)

please mark the thread as 'SOLVED' - Thanks!