开云体育

On Tue, May 10, 2022 at 05:36 AM, Peter Cook wrote:

Any insights / fixes would be appreciated.

My guess would be that the folks that own the mail server (121.200.0.92) have made a change and haven't got it set up correctly.? Sometimes things like that start working after a few people complain to the company and/or they finish the setup.? It looks like it's owned by an Australian company, if that helps any.

Duane
--
Lots of detailed information can be found in the Owners Manual and Members Manual.

Thanks Duane.? The user in question has queried why he only gets this error when he emails to groups.io, and not with other emails he sends to friends etc.? I imagine this may be due to particular (rigorous) configuration requirements of groups.io.

Would you mind offering a (very) brief explanation, so I can pass it on?

With thanks
Peter

no reverse DNS for 121.200.0.92

This has only just started happening to them in past couple of days

The member needs to tell technical support of their ISP to pass following to their sysadmin:

DNSSEC for the reverse zone is invalid: NS lookup with the "checking disabled" flag works but doesn't work normally (without that flag):

~ $ dig +cdflag -x 121.200.0.92 @8.8.8.8
...
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 34526
...
;; ANSWER SECTION:
92.0.200.121.in-addr.arpa. 3600 IN PTR smtp01.aussiebb.com.au.
...
~ $ dig -x 121.200.0.92 @8.8.8.8
...
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 23500