On Friday 8 February 2019 16:33:24 CET, Ned Freed wrote:
The few customers who have configured
things to return result mixtures involving temporary failures have generally
reported success, although there have been a few cases where it caused
I've seen it in practice, and I don't send that much mail, so I don't think
this is obscure. Postfix has done it since 2.1, released in 2003.
If you enable that on a secondary MX or SMTP-to-LMTP MTA, Postix will
usually issue 250/550 but if the LMTP server or primary MX is unreachable,
Postfix will issue a mixture of 250, 450 and 550.
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