NFCT(8)

NAME
nfct - command line tool to interact with the connection tracking system

SYNOPSIS
nfct subsystem command [parameters]

DESCRIPTION
nfct is the command line tool that allows you Netfilter's manipulate Connection Tracking System.

SUBSYS
By the time this manpage has been written, the supported subsystem are timeout

timeout
    The timeout subsystem allows you to define fine-grain timeout policies.

version
    Displays the version information.

help
    Displays the help message.

TIMEOUT SUBSYSTEM

list
    List the existing timeout policies.

add Add new timeout policy.

delete
    Delete timeout policy.

get Get existing timeout policy.

EXAMPLE

nfct timeout add test-tcp inet tcp established 100 close 10 close_wait 10

This creates a timeout policy for tcp using 100 seconds for the ESTABLISHED state, 10 seconds for CLOSE state and 10 seconds for the CLOSE_WAIT state.

Then, you can attach the timeout policy with the iptables CT target:

iptables -I PREROUTING -t raw -p tcp -j CT --timeout test-tcp

iptables -I OUTPUT -t raw -p tcp -j CT --timeout test-tcp

You can test that the timeout policy with:

conntrack -E -p tcp

It should display:

[UPDATE] tcp 6 100 ESTABLISHED src=192.168.39.100 dst=57.126.1.20 sport=56463 dport=80 src=57.126.1.20 dst=192.168.39.100 sport=80 dport=56463 [ASSURED]

SEE ALSO
iptables(8),conntrack(8)

BUGS
Please, report them to netfilter-devel@vger.kernel.org or file a bug in Netfilter's bugzilla (https://bugzilla.netfilter.org).

AUTHORS
Pablo Neira Ayuso wrote and maintains the nfct tool.

Man page written by Pablo Neira Ayuso <pablo@netfilter.org>.