Q: Why aren't we getting acknowledgement messages from our fax server?\
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Q: Why does mail to
\i user@host
\i0 — where
\i host
\i0 is on the local network — never get delivered, and yet I never get mail back from the Mailer Agent?\
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A: There's a bug in the
\b sendmail.sharedsubsidiary.cf
\b0 file in 1.0, 1.0a, 2.0, and 2.1. This file is used when a machine is configured as a mail client.\
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The fax daemon sends mail to
\i user%host
\i0 (which is, in this case, the same as sending it to
\i user@host
\i0 ). If the fax server is a mail client and the machine from which the user sent the fax is also a mail client then the acknowledgement will not be delivered.\
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To verify that this is the problem, look in the file
This error indicates that the message was sent back-and-forth between machines too many times. It's a symptom of this problem. (Words in
\f1\i\fs24 italics
\f0\i0\fs28 may be different on your system.)\
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The other way to verify: see if
\b sendmail.sharedsubsidiary.cf
\b0 is the
\b sendmail
\b0 configuration file being used (look in
\b /etc/sendmail
\b0 ).\
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Following are the differences between the 2.0
\b sendmail.sharedsubsidiary.cf
\b0 file and a file with the recommended modifications. (Modifications from the 1.0 version are nearly identical, modulo the few small changes made for 2.0 from 1.0.)\
\b0 macro) to indicate that it's no longer what's shipped with the release.\
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Modify the
\b etherl
\b0 mailer definition to remove the
\b C
\b0 flag, which controls sender domain addition.\
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Modify
\i Ruleset 0
\i0 to use the
\b etherl
\b0 mailer (rather than the
\b ether
\b0 mailer) when sending mail to another host on the local network.\
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These modifications must be installed on the machine from which the message is sent. But, the bug only shows up when both the sending and the receiving machine are mail clients. If you're only concerned with fax receipts (since, typically, users in a mail server-client network don't specify a hostname explicitly when sending mail to a local user) simply install the modified configuration file on the fax server.\
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(We recommend making a copy of
\b sendmail.sharedsubsidiary.cf
\b0 , editing that copy, and changing the symbolic link of