xtables-compat.8

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.TH XTABLES-COMPAT 8 "Mar 4, 2016"

.SH NAME
xtables-compat \- compat tools to migrate from iptables to nftables

.SH DESCRIPTION
\fBxtables-compat\fP is set of tools to help the system administrator migrate the
ruleset from \fBiptables(8)\fP, \fBip6tables(8)\fP, \fBarptables(8)\fP, and
\fBebtables(8)\fP to \fBnftables(8)\fP.

The \fBxtables-compat\fP set is composed of several commands:
.IP \[bu] 2
iptables-compat
.IP \[bu]
iptables-compat-save
.IP \[bu]
iptables-compat-restore
.IP \[bu]
ip6tables-compat
.IP \[bu]
ip6tables-compat-save
.IP \[bu]
ip6tables-compat-restore
.IP \[bu]
arptables-compat
.IP \[bu]
ebtables-compat

These tools use the libxtables framework extensions and hook to the nf_tables
kernel subsystem using the \fBnft_compat\fP module.

.SH USAGE
The compat tools set allows you to manage the nf_tables backend using the
native syntax of \fBiptables(8)\fP, \fBip6tables(8)\fP, \fBarptables(8)\fP, and
\fBebtables(8)\fP.

You should use the compat tools exactly the same way as you would use the
corresponding original tool.

Adding a rule will result in that rule being added to the nf_tables kernel
subsystem instead.
Listing the ruleset will use the nf_tables backend as well.

When these tools were designed, the main idea was to replace each legacy binary
with a symlink to the corresponding compat tool, for example:

.nf
	/sbin/iptables  --> /usr/sbin/iptables-compat
	/sbin/ip6tables --> /usr/sbin/ip6tables-compat
	/sbin/arptables --> /usr/sbin/arptables-compat
	/sbin/ebtables  --> /usr/sbin/ebtables-compat
.fi

.SH EXAMPLES
One basic example is creating the skeleton ruleset in nf_tables from the
compat tools, in a fresh machine:

.nf
	root@machine:~# iptables-compat -L
	[...]
	root@machine:~# ip6tables-compat -L
	[...]
	root@machine:~# arptables-compat -L
	[...]
	root@machine:~# ebtables-compat -L
	[...]
	root@machine:~# nft list ruleset
	table ip filter {
		chain INPUT {
			type filter hook input priority 0; policy accept;
		}

		chain FORWARD {
			type filter hook forward priority 0; policy accept;
		}

		chain OUTPUT {
			type filter hook output priority 0; policy accept;
		}
	}
	table ip6 filter {
		chain INPUT {
			type filter hook input priority 0; policy accept;
		}

		chain FORWARD {
			type filter hook forward priority 0; policy accept;
		}

		chain OUTPUT {
			type filter hook output priority 0; policy accept;
		}
	}
	table bridge filter {
		chain INPUT {
			type filter hook input priority -200; policy accept;
		}

		chain FORWARD {
			type filter hook forward priority -200; policy accept;
		}

		chain OUTPUT {
			type filter hook output priority -200; policy accept;
		}
	}
	table arp filter {
		chain INPUT {
			type filter hook input priority 0; policy accept;
		}

		chain FORWARD {
			type filter hook forward priority 0; policy accept;
		}

		chain OUTPUT {
			type filter hook output priority 0; policy accept;
		}
	}
.fi

(please note that in fresh machines, listing the ruleset for the first time
results in all tables an chain being created).

To migrate your complete filter ruleset, in the case of \fBiptables(8)\fP,
you would use:

.nf
	root@machine:~# iptables-save > myruleset		# reads from x_tables
	root@machine:~# iptables-compat-restore myruleset	# writes to nf_tables
.fi


.SH LIMITATIONS
You should use \fBLinux kernel >= 4.2\fP.

Some (few) extensions may be not supported (or fully-supported) for whatever
reason (for example, they were considered obsolete).

To get up-to-date information about this, please head to
\fBhttp://wiki.nftables.org/\fP.

.SH AUTHORS
The nftables framework was written by Patrick McHardy <kaber@trash.net> and
Pablo Neira Ayuso <pablo@netfilter.og>.

This manual page was written by Arturo Borrero Gonzalez
<arturo@debian.org> for the Debian project.

This documentation is free/libre under the terms of the GPLv2+.