Postfix, after expanding the alias, is not transmitting the original
envelope recipient email address to dovecot and cannot record it in a
Received: header.
The LMTP DSN extension allows postfix to specify an ORCPT= parameter to
the "RCPT TO:" line (in postfix src/smtp/smtp_proto.c). However, dovecot
does not support the DNS extension on the LMTP endpoint. It has
preliminary support of the ORCPT parameter in latest versions but is is
disabled and not working.
The solution taken was to add a sieve script to parse the Received:
header written by postfix and parse the original RCPT TO address from
it. Then add the header through the "editheader" sieve extension. Later
sieve scripts can take this header to perform further filtering.
Allows to use mailu without docker-compose when hostnames are not set up
by docker itself but provided via a separate resolver.
Use case: use mailu using nomad scheduler and consul resolver instead of
docker-compose. Other servers are provided by the DNS resolver that
resolves names like admin.service.consul or webmail.service.consul.
These names needs to be configurable.
See https://www.endpoint.com/blog/2015/05/28/postfix-address-verification
Block client until address verifiction is completed and mail will not be rejected by relaying MTA or smarthost.
If verification fails, mail is rejected.
If verification takes too long, mail is temporaryly rejected and sending client will retry later.
Scott