SMTP runs on a specific port.. it's odd that the port number would change for that standard protocol.
Apparently you use the DAEMON_OPTION
macro to change the listening port in Sendmail.
no_default_msa Don't generate the default MSA daemon, i.e.,
To define a MSA daemon with other parameters, use this
FEATURE and introduce new settings via DAEMON_OPTIONS().
ClientPortOptions and DaemonPortOptions are special cases since multiple
clients/daemons can be defined. This can be done via
Note that multiple CLIENT_OPTIONS() commands (and therefore multiple
ClientPortOptions settings) are allowed in order to give settings for each
protocol family (e.g., one for Family=inet and one for Family=inet6). A
restriction placed on one family only affects outgoing connections on that
If DAEMON_OPTIONS is not used, then the default is
DAEMON_OPTIONS(`Port=587, Name=MSA, M=E')
If you use one DAEMON_OPTIONS macro, it will alter the parameters
of the first of these. The second will still be defaulted; it
represents a "Message Submission Agent" (MSA) as defined by RFC
2476 (see below). To turn off the default definition for the MSA,
use FEATURE(`no_default_msa') (see also FEATURES). If you use
additional DAEMON_OPTIONS macros, they will add additional daemons.
Example 1: To change the port for the SMTP listener, while
still using the MSA default, use
Example 2: To change the port for the MSA daemon, while still
using the default SMTP port, use
DAEMON_OPTIONS(`Port=987, Name=MSA, M=E')
Note that if the first of those DAEMON_OPTIONS lines were omitted, then
there would be no listener on the standard SMTP port.