iptables(8) - Linux man page
https://linux.die.net/man/8/iptables
Iptables is used to set up, maintain, and inspect the tables of IP packet filter rules in the Linux kernel. iptables - administration tool for IPv4 packet filtering and NAT.
iptables - Wikipedia
https://en.wikipedia.org/wiki/Iptables
iptables is a user-space utility program that allows a system administrator to configure the IP packet filter rules of the Linux kernel firewall, implemented as different Netfilter modules. The filters are organized in different tables, which contain chains of rules for how to treat network traffic packets.
netfilter/iptables project homepage - The netfilter.org project
https://iptables.org/
iptables is a generic firewalling software that allows you to define rulesets. nftables is the successor of iptables, it allows for much more flexible, scalable and performance packet classification.
Iptables for beginners - Linux Hint
https://linuxhint.com/iptables_for_beginners/
Iptables is basically the main firewall used for Linux systems, allows you to instruct your system to accept, refuse or forward a connection depending on chosen parameters.
IptablesHowTo - Community Help Wiki | Saving iptables
https://help.ubuntu.com/community/IptablesHowTo
Basic iptables howto. Iptables is a firewall, installed by default on all official Ubuntu distributions Editing iptables. The only problem with our setup so far is that even the loopback port is blocked.
Manpage of IPTABLES
https://www.opennet.ru/docs/RUS/iptables/misc/iptables-tutorial/other/iptables.html
iptables -[ADC] chain rule-specification [options] iptables -[RI] chain rulenum rule-specification Several different tables may be defined. Each table contains a number of built-in chains and may...
iptables - ArchWiki
https://wiki.archlinux.org/index.php/iptables
iptables is a command line utility for configuring Linux kernel firewall implemented within the Netfilter project. The term iptables is also commonly used to refer to this kernel-level firewall. It can be configured directly with iptables...