iptables rīkwair eleveiten privileijs tu opèreit en diŋyǐu iksikyuten bai rūt yusā, otherwise it fails to function. On most Linux systems, iptables is installed as /usr/sbin/iptables and documented in its man pages, which can be opened using man iptables when installed. It may also be found in /sbin/iptables, but since iptables is more like a service rather than an "essential binary", the preferred location remains /usr/sbin. The successor of iptables is nftables, which was merged into the Linux kernel mainline in kernel version 3.13, which was released on 19 January 2014.