mxallowd

Anti-Spam-Daemon using nolisting/iptables

Install

All systems
curl cmd.cat/mxallowd.sh
Debian Debian
apt-get install mxallowd
Ubuntu
apt-get install mxallowd
Windows (WSL2)
sudo apt-get update sudo apt-get install mxallowd
Raspbian
apt-get install mxallowd

mxallowd

Anti-Spam-Daemon using nolisting/iptables

mxallowd is a daemon for linux/netfilter(iptables) which uses nolisting (http://nolisting.org). That means, you define two MX-servers in your nameserver and mxallowd will block the access to any of these mailservers if the client did not try the other one. This blocks non-RFC-compliant mailers, which are often in use by spammers and so-called direct-to-second-mx which is also a technique mainly used by spammers.