Quoting John Levine via Exim-users (exim-users@lists.exim.org): > >That text is obsolete. There is no such text in RFC5321, and > >CNAME-valued mail domains have long been OK. The sending MTA (its DNS > >resolver) is expected to restart the MX lookup at the target of the > >CNAME, and if no MX records are found, use the final A/AAAA records. > > Huh, you're right. In my minor defense, the CNAME code was written in > 1998, RFC 2821 was published in 2001, and as far as I can tell this is > the first time in 20 years that I've sent to a CNAME'd domain that > caused a problem. I'll go patch the code.
Exim has the same CNAME "bug" left over from those times. https://bugs.exim.org/show_bug.cgi?id=1383 Though it works in different mysterious ways routing bounces back as can be seen in the examples in that bug report. ;) -- | 't Gaat om 't spel, niet om de knikkers! | 4096R/20CC6CD2 - 6D40 1A20 B9AA 87D4 84C7 FBD6 F3A9 9442 20CC 6CD2 -- ## subscription configuration (requires account): ## https://lists.exim.org/mailman3/postorius/lists/exim-users.lists.exim.org/ ## unsubscribe (doesn't require an account): ## exim-users-unsubscr...@lists.exim.org ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
