Logging with IPTables requires the use of an extra IPTables extension called NFLOG (https://manpages.debian.org/experimental/iptables/iptables-extensions.8.en.html#NFLOG) and a separate daemon process, called ulogd2 (https://www.netfilter.org/projects/ulogd/index.html). Ulogd2 reads out the packets sent to the above mentioned extension and stores them in local files or databases. First, install the ulogd2 package (example is based on Debian/ Ubuntu): Example: log and…
