Re: Securing Sendmail 8.11.6-23 from spammers

Hi Kevin,

> Running RedHat 7.2, with sendmail version 8.11.6-23.72.  Need to secure
> the mail server; so only our group of users
> could send and receive e-mails, and anybody else to get bounced out.
> How do set it up.  Please lead me in the right
> direction. Thanks -- Kevin

To start out with, follow the directions on the recent CERT advisory
regarding sendmail, or switch smtp servers.

You need to specify if you're users are on a private network or if you
want them to be able to relay from remote connections. Relaying from
remote connectins is not advised, and can be a problem with some ISPs. The
practice is getting standardized to having remote users use the local ISP
smtp services and to recieve mail via your server. However, if you insist,
look up SMTP-Auth.

OTOH, I dunno about sendmail, but for postfix the setup for relaying only
for the local network is a matter of editing one line in the conf.

HTH

-- 
Keith Mastin
BeechTree Information Technology Services Inc.
Toronto, Canada
(416)696-6070