Getting DNS Errors RSS


I'm getting a bunch of DNS errors now for months. I didn't used to get them so was wondering if anyone else has the issue. All are similar to the one below. I have changed the DNS in orf to use external dns servers and our ISP's dns server but getting the same issue. I have increased to time to 15 seconds for timeout and still getting them. DNS is working as the orf server is able to nslookup these urls.
Server: local dns server
Address: 10.0.0.x

Non-authoritative answer:

Server: local dns server
Address: 10.0.0.x

*** local dns server can't find Non
-existent domain
Error in ORF
Time: 4/12/2018 14:18:48 GMT-0400 Eastern Daylight Time
Sender Email:
Recipient Email: lg******@***.org
Related IP:
Action: (not available)
Email Subject: (not available)

DNS error. Test: "DNSBL: HOSTKARMA", built-in DNS resolver, domain: "", record type: A. DNS timeout error.

Filtering Point: Before Arrival
Event Class: System Message
Severity: Warning
Server: *******
Event Source: MSEXCHANGE
HELO Domain:
Message ID: (not available)
Log Mode: Verbose
ORF Version: 5.4.1 REGISTERED

Any help would be helpful. Thanks.

by jean.davis 6 months ago

@jean.davis: Hello jean.davis,

Most online DNSBL services refuse to reply to queries (i.e. the queries time out) that originate from public DNS resolvers, such as ISP DNS resolvers or Google's DNS servers, so you should not use them in ORF - not even as a "fallback" option. If you want to use external servers, make sure that they comply with ORF's DNS requirements:

by Daniel Novak (Vamsoft) 6 months ago
(in reply to this post)


The error is with the builtin btw.

by jean.davis 6 months ago

Found the problem to be DNS Rebinding Attack Prevention on our Sonicwall firewall. Sorry to raise concerns here.

by jean.davis 6 months ago

Thank you for the update Jean. I am glad to hear that you have found the source of the issue.

by Daniel Novak (Vamsoft) 6 months ago

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