You know those same hosts, providers, or whole networks, who get through your spam filter and spam your users with the same content over and over again. By building up your blacklist in Postfix, you can stop them from bothering you and your users. We will explain how local blacklists work in Postfix and how to use them with whitelists to have better control and reduce errors.
Check before you blacklist Blocking other hosts must be a well-thought decision because blocking single hosts, IP addresses, or even whole networks will stop all delivery attempts to your mail servers.
If you use any blacklists for email services, whitelisting important Hosts, single IP Addresses, and even whole networks is an essential task. By whitelisting valuables email services to your users or even customers, you as admin won’t reject important email communication.
Blacklisting in Postfix If you use any blacklist service or has your blacklist in your Postfix setup, you will probably find similar logs:
root@server $ grep "blocked using" /var/log/mail.log Dec 17 4:07:18 server postfix/smtpd[21213]: NOQUEUE: reject: RCPT from unknown[1.
Forward MailMum offers individual services for email administrators to monitor incoming mail traffic and to control it by blocking IP addresses or even IP networks of abusive systems using Real-time Blackhole List (RBL) technology. The admin has full control over the listings by defining parameters, blacklisted (abusive), and whitelisted (trusted) IP addresses. The defined rules may apply for the whole account down to an individual server.
Mail System Today Provided by several sources email traffic is up to 90% or unwanted emails (called spam or junk).
A name, domain, logo, and a draft website - this is the way MailMum was born out of an internal project.
From a necessity to this service MailMum was born out of a need to face problems with unwanted emails called spam or junk. As filters like Spamassassin were good, but spammers are human, their job is to figure out how to bypass them. They will try and will find ways to reach your inbox.