Illustrated introduction to Linux iptables Gee, it's my turn to throw some light on iptables! There are hundreds or even thousands of articles on the topic out there, including introductory ones. I'm not going to put either formal definitions here nor long lists of useful commands. I would rather try to use layman's terms and scribbling as much as possible to give you some insights about the domain before going to all these tables, rules, targets, and policies. Networking
How nftables log to external file Logging traffic blocked by the nftables or iptables firewall rules is necessary for debugging the firewall rules and to be alerted to local software problems. Any packet matching a rule can be logged by using -j LOG target for iptables or log statement for nftables. Logging packet has no effect on the packet's disposition, however. The packet must match an accept or drop rule. Linux Security Networking
