On 17/04/2023 14:08, Bill Cole via Exim-users wrote:
There's a rational basis for an exception for 5xx before MAIL FROM, when the target only has the connection parameters and HELO name to use as a basis for rejection. Re-routing via a fallback path isn't entirely unjustifiable in that case, as it changes those elements of the transaction.
Exim treats what you're talking of as a "host error" rather than a "message error", and goes on to try the next host in the list of possibles determined by the routing stage. Commonly that would be a lower-priority MX for the domain. -- Cheers, Jeremy -- ## List details at https://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/
