Ron Johnson wrote:
If so, then does Postfix, as the default MTA for the debian system,The default MTA is still exim, isn't it?In Debian, yes. In the Unix world in general, it still appears to be sendmail.But since all(?) MTAs provide a /usr/sbin/sendmail, it's irrelevant to the user, no?
It is relevant in that exim can be configured beautifully while configuring sendmail is configuring sendmail.
The functionality is similar; I don't know if there are things that can be done with exim only but not with sendmail, and vice versa.
Thus, the appearance to the user is that he can or can not send and receive mail, provided that a user is someone who doesn't care about mail servers and hence doesn't experience the fun of configuring exim or the configuring of configuring sendmail :)
GH