address literals rejected

[Aza]

MXtoolbox and various mail configuration checkers note that my CentOS7 server with exim from a default DirectAdmin installation has problems with "Acceptance of address literals". Here's the error from MXtoolbox:

Mailserver rejected mail to address literals. Mailservers are technically required by RFC1123 section 5.2.17 to accept mail to domain literals (i.e. IP addresses instead of domains). This ensures backwards compatibility and can help with delivery in certain non-optimal situations, like a DNS server being down/unresponsive.
69.197.159.85 | unexpected response to [RCPT TO: ] | 501 : domain literals not allowed

Do any of the assembled eyes have a suggestion for where one goes to correct this -- and how one corrects this?

 

[wattie]

This is not a problem - just a warning for something that was important in the 90s

It can be eventually enabled through exim.conf (not sure if there is even an option in the new versions of the spamblocker one). It should work only if the domain is on a dedicated IP, not on a shared one.

Dig into that only if you really need to send to [email protected] (eg <name>@<ip> - something that nobody does nowadays).