Avoiding Mail Server Inconvenience

Question

We run our own web server (Apache on Ubuntu) for a bunch of non-commercial websites, but there was no mail transfer agent installed on it, since they are complex to configure and maintain. You need to take care of spams, viruses, other attacks and authentication (for not being classified as spam by other servers). And you should always keep an eye on it.

Thus, we have been using free Google Apps and Yandex services for email.

But we need to have some contact forms on our websites and receive important warnings from cron scripts.

I installed Postfix yesterday and I have already started seeing spam warnings in my log file.

I know I can use a mail service on another server over SMTP for web forms. But, I don't know what can I do to get the necessary messages from cron scripts.

Is there an easy way of avoiding all this extra work?

Answer 1

Do either or both of

• Configure postfix to ignore incoming SMTP connections that originate outside your LAN (or outside computer itself)
• Configure Ubuntu firewall to block incoming SMTP connections.

---

/etc/postfix/main.cf:
    # Allow connections from trusted networks only.
    smtpd_client_restrictions = permit_mynetworks, reject