diff options
Diffstat (limited to 'man/systemd.network.xml')
| -rw-r--r-- | man/systemd.network.xml | 37 |
1 files changed, 18 insertions, 19 deletions
diff --git a/man/systemd.network.xml b/man/systemd.network.xml index 5994869d97..e6dedb027d 100644 --- a/man/systemd.network.xml +++ b/man/systemd.network.xml @@ -363,29 +363,28 @@ </varlistentry> <varlistentry> <term><varname>IPForward=</varname></term> - <listitem><para>Configures IP forwarding for the network - interface. If enabled, incoming packets on the network - interface will be forwarded to other interfaces according to - the routing table. Takes either a boolean argument, or the - values <literal>ipv4</literal> or <literal>ipv6</literal>, - which only enables IP forwarding for the specified address - family, or <literal>kernel</literal>, which preserves existing sysctl settings. - This controls the - <filename>net.ipv4.conf.<interface>.forwarding</filename> - and - <filename>net.ipv6.conf.<interface>.forwarding</filename> - sysctl options of the network interface (see <ulink + <listitem><para>Configures IP packet forwarding for the + system. If enabled, incoming packets on any network + interface will be forwarded to any other interfaces + according to the routing table. Takes either a boolean + argument, or the values <literal>ipv4</literal> or + <literal>ipv6</literal>, which only enable IP packet + forwarding for the specified address family. This controls + the <filename>net.ipv4.ip_forward</filename> and + <filename>net.ipv6.conf.all.forwarding</filename> sysctl + options of the network interface (see <ulink url="https://www.kernel.org/doc/Documentation/networking/ip-sysctl.txt">ip-sysctl.txt</ulink> for details about sysctl options). Defaults to <literal>no</literal>.</para> - <para>Note: unless this option is turned on, or set to <literal>kernel</literal>, - no IP forwarding is done on this interface, even if this is - globally turned on in the kernel, with the - <filename>net.ipv4.ip_forward</filename>, - <filename>net.ipv4.conf.all.forwarding</filename>, and - <filename>net.ipv6.conf.all.forwarding</filename> sysctl - options.</para> + <para>Note: this setting controls a global kernel option, + and does so one way only: if a network that has this setting + enabled is set up the global setting is turned on. However, + it is never turned off again, even after all networks with + this setting enabled are shut down again.</para> + + <para>To allow IP packet forwarding only between specific + network interfaces use a firewall.</para> </listitem> </varlistentry> <varlistentry> |