MH-MTS(8)MH-MTS(8)NAMEmh-mts - the nmh interface to the message transport system
SYNOPSIS
SendMail
Zmailer
MMDF (any release)
stand-alone
DESCRIPTION
THIS IS OUT OF DATE AND NEEDS REWORKING.
nmh can use a wide range of message transport systems to
deliver mail. Although the nmh administrator usually
doesn't get to choose which MTS to use (since it's already
in place), this document briefly describes the interfaces.
When communicating with SendMail, nmh always uses the SMTP
to post mail. Depending on the nmh configuration, Send-
Mail may be invoked directly (via a fork and an exec), or
nmh may open a TCP/IP connection to the SMTP server on the
localhost.
When communicating with zmailer, the SendMail compatibil-
ity program is required to be installed in /usr/lib. nmh
communicates with zmailer by using the SMTP. It does this
by invoking the /usr/lib/sendmail compatibility program
directly, with the `-bs' option.
When communicating with MMDF, normally nmh uses the "mm_"
routines to post mail. However, depending on the nmh con-
figuration, nmh instead may open a TCP/IP connection to
the SMTP server on the localhost.
If you are running a UNIX system with TCP/IP networking,
then it is felt that the best interface is achieved by
using either SendMail or MMDF with the SMTP option. This
gives greater flexibility. To enable this option you
append the /smtp suffix to the mts option in the nmh con-
figuration. This yields two primary advantages: First,
you don't have to know where submit or SendMail live.
This means that nmh binaries (e.g., post ) don't have to
have this information hard-coded, or can run different
programs altogether; and, second, you can post mail with
the server on different systems, so you don't need either
MMDF or SendMail on your local host. Big win in conserv-
ing cycles and disk space. Since nmh supports the notion
of a server search-list in this respect, this approach can
be tolerant of faults. Be sure to set "servers:" as
described in mh-tailor(8) if you use this option.
[nmh-1.0.4] MH.6.8 1
MH-MTS(8)MH-MTS(8)
There are four disadvantages to using the SMTP option:
First, only UNIX systems with TCP/IP are supported. Sec-
ond, you need to have an SMTP server running somewhere on
any network your local host can reach. Third, this
bypasses any authentication mechanisms in MMDF or Send-
Mail. Fourth, the file /etc/hosts is used for hostname
lookups (although there is an exception file). In
response to these disadvantages though: First, there's got
to be an SMTP server somewhere around if you're in the
Internet or have a local network. Since the server
search-list is very general, a wide-range of options are
possible. Second, SMTP should be fixed to have authenti-
cation mechanisms in it, like POP. Third, nmh won't choke
on mail to hosts whose official names it can't verify,
it'll just plug along (and besides if you enable the DUMB
configuration options, nmh ignores the hosts file alto-
gether).
FILES
/usr/contrib/mh/etc/mts.conf nmh mts configuration file
PROFILE COMPONENTS
None
SEE ALSO
MMDF-II: A Technical Review, Proceedings, Usenix Summer
'84 Conference
SENDMAIL -- An Internetwork Mail Router
mh-tailor(8), post(8)DEFAULTS
None
CONTEXT
None
BUGS
The /usr/contrib/mh/etc/mts.conf file ignores the informa-
tion in the MMDF-II tailoring file.
[nmh-1.0.4] MH.6.8 2
