Re: [exim] NDN, Mailer-Daemon, DSN - EXIM

On 12/04/18 09:42, Mike Brudenell via Exim-users wrote:
> On 11 April 2018 at 19:43, Jeremy Harris via Exim-users <exim-users@???
>> wrote:
>
>> That would be incorrect per standards. The HELO name should identify
>> the sending system.
>>
>
> Umm… Agreed, but what if this mysterious and obfuscated organisation has
> multiple A records under different domain names pointing at the system Exim
> is running on? Wouldn't it then be valid to use any of those in the
> HELO/EHLO command? E.g.,
>

>    - a.example.com is an A record pointing at ww.xx.yy.zz
>    - b.example.net is an A record pointing at ww.xx.yy.zz

>
> Wouldn't it then be permissible to use a.example.com in the HELO/EHLO when
> sending from an "@a.example.com" address, but b.example.net when sending
> from an "@b.example.net" address?

Yes. Because both cases identify the sending system.
--
Jeremy