FEATURE(accept_unqualified_senders)
Allow unqualified MAIL From: V8.9 and later
The MAIL From:
command of the SMTP transaction is used to convey
the address of the envelope sender. RFC821 requires
that the envelope sender address always be fully
qualified. That is, it must always have a user part,
an @
character,
and a domain part, in that order.
The normal behavior of sendmail is to reject the envelope sender if it is not fully qualified. For example:
MAIL From: <you> 553 5.5.4 <you>... Domain name required
This rejection is done for network connections only.
When reading the envelope sender via the standard
input under the -bs
command-line switch (-bs on page 236) a missing
@domain part is OK:
%/usr/sbin/sendmail -bs
220 yourhost.domain ESMTP Sendmail 8.14.1/8.14.1; Fri, 14 Dec 2007 14:13:09 −0700HELO yourhost
250 yourhost.domain Hello your@yourhost.domain, pleased to meet youMAIL From: <bob>
250 2.1.0 <bob>... Sender ok
If machines at your site routinely send unqualified envelope sender addresses (addresses without the @domain part), you will find that mail is being rejected.
Your first attempt at a solution should be to fix the
broken software that is sending unqualified
addresses. If that fails, or if you lack the
permission or authority, you can use this accept_unqualified_senders
feature to
force sendmail to accept
unqualified envelope sender addresses:
FEATURE(`accept_unqualified_senders')
Another way to handle this problem is with the (V8.10
and later) DaemonPortOptions
option’s ...
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