moderated #misc Issue with bouncing messages (seems as mail from groups.io is sent to wrong mail server) #misc


YT9TP - Pedja
 

I've got message from groups.io that mail sent to me is bouncing. Followed the link to check it out.

In Recent Bounces I found out list of bounce notification from several dates all with similar message like this one:

96.31.72.43: 550 Please turn on SMTP Authentication in your mail client. web01.groups.io [66.175.222.12]:53022 is not permitted to relay through this server without authentication.

I checked logs of my mail server and found out no traces of these connections and bounces.

Then I realized that it seems messages are bounced by mail server at 96.31.72.43. That is IP of server where my domain is hosted. Server does have mail server but for this specific domain, MX record is set for different address, meaning mail server at 96.31.72.43 is not used but other one, as specified in MX for this domain.

It seems to me that groups.io occasionally tries to send mail to me using IP address of a domain instead of IP address as specified in MX, and, as expected, that server refuses to accept mail.

As my email is on several groups at groups.io I receive mail from there regularly. It seems groups.io usually properly sends mail using MX information, but occasionally uses domain address instead and then bounce occurres.

I see no way how can I handle such bounces.


Jim Wilson
 

On Mon, Jun 7, 2021 at 06:03 PM, YT9TP - Pedja wrote:
66.175.222.12
The IP address, 66.175.222.12, is on SORBS Spam list and may play a part in this issue. It would be necessary to supply the domain name in order to investigate the issue. That said, I cannot imagine this would "occasionally" be anything other than some type of DNS configuration issue since it is the sole source of determining where an email is attempted to be sent.
 
--
Jim


Duane
 

On Tue, Jun 8, 2021 at 07:42 AM, Jim Wilson wrote:
SORBS Spam list
SORBS is notorious for false positives (and lack of cooperation), https://beta.groups.io/g/main/message/27122

Duane


 

On Mon, Jun 7, 2021 at 4:03 PM YT9TP - Pedja via groups.io <yt9tp=uzice.net@groups.io> wrote:
I've got message from groups.io that mail sent to me is bouncing. Followed the link to check it out.

In Recent Bounces I found out list of bounce notification from several dates all with similar message like this one:

96.31.72.43: 550 Please turn on SMTP Authentication in your mail client. web01.groups.io [66.175.222.12]:53022 is not permitted to relay through this server without authentication.

I checked logs of my mail server and found out no traces of these connections and bounces.

Then I realized that it seems messages are bounced by mail server at 96.31.72.43. That is IP of server where my domain is hosted. Server does have mail server but for this specific domain, MX record is set for different address, meaning mail server at 96.31.72.43 is not used but other one, as specified in MX for this domain.


Usually what this means is that we had a problem looking up the MX record for your domain and fell back on using the A record. I don't know why we had a problem with the lookup, but it appears to be temporary.

Thanks,
Mark


YT9TP - Pedja
 

Usually what this means is that we had a problem looking up the MX record for
your domain and fell back on using the A record. I don't know why we had a
problem with the lookup, but it appears to be temporary.
I agree. This happens quite rarely but it efficiently and promptly disables me getting email. I follow some pretty important groups and this is problem, that I miss some emails until I found out there is an issue. That is the reason I am trying to resolve this.

One of the solutions may be that groups.io is set to be less rigid on bounces (at least these ones), to avoid these temporary glitches to deactivate emails.

The IP address, 66.175.222.12, is on SORBS Spam list and may play a part in this issue.
It does not get to the point to check SORBS. Mail is sent to server that is not accepting mail for specified domain so it rejects it promptly.

It would be necessary to supply the domain name in order to investigate the issue. That
said, I cannot imagine this would "occasionally" be anything other than some type of DNS
configuration issue since it is the sole source of determining where an email is attempted
to be sent.
Domain is in my email address: uzice.net


YT9TP - Pedja
 

I still have this issue. It seems evident that groups.io occasionally sends mail to wrong server, not following MX records for receiving domain.




6:17pm #22929 [nanovna-users] Nano-F - Did I make a Mistake? 96.31.72.43: 550 Please turn on SMTP Authentication in your mail client. web01.groups.io [66.175.222.12]:38666 is not permitted to relay through this server without authentication.
5:26pm #22925 [nanovna-users] Off topic, but still RF 96.31.72.43: 550 Please turn on SMTP Authentication in your mail client. web01.groups.io [66.175.222.12]:54350 is not permitted to relay through this server without authentication.
Jun 23 #22907 [nanovna-users] Charging LED Operation on NanoVNA-H4 96.31.72.43: 550 Please turn on SMTP Authentication in your mail client. web01.groups.io [66.175.222.12]:43750 is not permitted to relay through this server without authentication.
Jun 21 #22885 [nanovna-users] NanoVNA-Saver on Windows 10 96.31.72.43: 550 Please turn on SMTP Authentication in your mail client. web01.groups.io [66.175.222.12]:52080 is not permitted to relay through this server without authentication.
Jun 21 #22882 [nanovna-users] NanoVnaSaver version 0.3.9 96.31.72.43: 550 Please turn on SMTP Authentication in your mail client. web01.groups.io [66.175.222.12]:56252 is not permitted to relay through this server without authentication.
Jun 20 #22845 [nanovna-users] NanoVNA-saver on Windows 96.31.72.43: 550 Please turn on SMTP Authentication in your mail client. web01.groups.io [66.175.222.12]:51414 is not permitted to relay through this server without authentication.
Jun 20 #22844 [nanovna-users] Opinions about the NanoVNA-F V2 96.31.72.43: 550 Please turn on SMTP Authentication in your mail client. web01.groups.io [66.175.222.12]:38940 is not permitted to relay through this server without authentication.