Re: disabling certain users from receiving external e-mail messages

In <1153068131.741017.279810@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>, on 16 Jul
2006 09:42:11 -0700, bellutta@xxxxxxxxx wrote:
I'm running my DNS/Mail server (sendmail) on a Fedora Core 3 box. By
default every user I
have in my /etc/passwd can send/receive e-mail messages. Is it
possible to configure sendmail so that e-mail messages that do not
originate from localhost will bounce back?

Yes.

To rephrase: I want to have some users to be able to receive messages
that are local, and only a specific set of users be able to receive
messages from any other hosts.

I want to do it in a way so that from the outside world these users do
not exist:

----- The following addresses had permanent fatal errors -----
<user@domain>
(reason: 550 5.1.1 <user@domain>... User unknown)

----- Transcript of session follows -----
... while talking to domain.:
DATA
<<< 550 5.1.1 <user@domain>... User unknown
550 5.1.1 <user@domain>... User unknown
<<< 503 5.0.0 Need RCPT (recipient)

Put the appropriate entry into your access file. It'll
most likely be at /etc/mail/access.

The first few lines of that file will give you the location
of the pertinent README file. There'll also probably be a
few example lines.
.