nixpkgs/nixos/doc/manual/configuration/firewall.xml
Eelco Dolstra b0ccd6dd16
Revert "nixos/doc: re-format"
This reverts commit ea6e8775bd. The new
format is not an improvement.
2019-09-19 19:17:30 +02:00

38 lines
1.3 KiB
XML

<section xmlns="http://docbook.org/ns/docbook"
xmlns:xlink="http://www.w3.org/1999/xlink"
xmlns:xi="http://www.w3.org/2001/XInclude"
version="5.0"
xml:id="sec-firewall">
<title>Firewall</title>
<para>
NixOS has a simple stateful firewall that blocks incoming connections and
other unexpected packets. The firewall applies to both IPv4 and IPv6 traffic.
It is enabled by default. It can be disabled as follows:
<programlisting>
<xref linkend="opt-networking.firewall.enable"/> = false;
</programlisting>
If the firewall is enabled, you can open specific TCP ports to the outside
world:
<programlisting>
<xref linkend="opt-networking.firewall.allowedTCPPorts"/> = [ 80 443 ];
</programlisting>
Note that TCP port 22 (ssh) is opened automatically if the SSH daemon is
enabled (<option><xref linkend="opt-services.openssh.enable"/> =
true</option>). UDP ports can be opened through
<xref linkend="opt-networking.firewall.allowedUDPPorts"/>.
</para>
<para>
To open ranges of TCP ports:
<programlisting>
<xref linkend="opt-networking.firewall.allowedTCPPortRanges"/> = [
{ from = 4000; to = 4007; }
{ from = 8000; to = 8010; }
];
</programlisting>
Similarly, UDP port ranges can be opened through
<xref linkend="opt-networking.firewall.allowedUDPPortRanges"/>.
</para>
</section>