.. SPDX-License-Identifier: GPL-2.0

=======================================
DSA switch configuration from userspace
=======================================

The DSA switch configuration is not integrated into the main userspace
network configuration suites by now and has to be performed manualy.

.. _dsa-config-showcases:

Configuration showcases
-----------------------

To configure a DSA switch a couple of commands need to be executed. In this
documentation some common configuration scenarios are handled as showcases:

*single port*
  Every switch port acts as a different configurable Ethernet port

*bridge*
  Every switch port is part of one configurable Ethernet bridge

*gateway*
  Every switch port except one upstream port is part of a configurable
  Ethernet bridge.
  The upstream port acts as different configurable Ethernet port.

All configurations are performed with tools from iproute2, which is available
at https://www.kernel.org/pub/linux/utils/net/iproute2/

Through DSA every port of a switch is handled like a normal linux Ethernet
interface. The CPU port is the switch port connected to an Ethernet MAC chip.
The corresponding linux Ethernet interface is called the master interface.
All other corresponding linux interfaces are called slave interfaces.

The slave interfaces depend on the master interface. They can only brought up,
when the master interface is up.

In this documentation the following Ethernet interfaces are used:

*eth0*
  the master interface

*lan1*
  a slave interface

*lan2*
  another slave interface

*lan3*
  a third slave interface

*wan*
  A slave interface dedicated for upstream traffic

Further Ethernet interfaces can be configured similar.
The configured IPs and networks are:

*single port*
  * lan1: 192.0.2.1/30 (192.0.2.0 - 192.0.2.3)
  * lan2: 192.0.2.5/30 (192.0.2.4 - 192.0.2.7)
  * lan3: 192.0.2.9/30 (192.0.2.8 - 192.0.2.11)

*bridge*
  * br0: 192.0.2.129/25 (192.0.2.128 - 192.0.2.255)

*gateway*
  * br0: 192.0.2.129/25 (192.0.2.128 - 192.0.2.255)
  * wan: 192.0.2.1/30 (192.0.2.0 - 192.0.2.3)

.. _dsa-tagged-configuration:

Configuration with tagging support
----------------------------------

The tagging based configuration is desired and supported by the majority of
DSA switches. These switches are capable to tag incoming and outgoing traffic
without using a VLAN based configuration.

single port
~~~~~~~~~~~

.. code-block:: sh

  # configure each interface
  ip addr add 192.0.2.1/30 dev lan1
  ip addr add 192.0.2.5/30 dev lan2
  ip addr add 192.0.2.9/30 dev lan3

  # The master interface needs to be brought up before the slave ports.
  ip link set eth0 up

  # bring up the slave interfaces
  ip link set lan1 up
  ip link set lan2 up
  ip link set lan3 up

bridge
~~~~~~

.. code-block:: sh

  # The master interface needs to be brought up before the slave ports.
  ip link set eth0 up

  # bring up the slave interfaces
  ip link set lan1 up
  ip link set lan2 up
  ip link set lan3 up

  # create bridge
  ip link add name br0 type bridge

  # add ports to bridge
  ip link set dev lan1 master br0
  ip link set dev lan2 master br0
  ip link set dev lan3 master br0

  # configure the bridge
  ip addr add 192.0.2.129/25 dev br0

  # bring up the bridge
  ip link set dev br0 up

gateway
~~~~~~~

.. code-block:: sh

  # The master interface needs to be brought up before the slave ports.
  ip link set eth0 up

  # bring up the slave interfaces
  ip link set wan up
  ip link set lan1 up
  ip link set lan2 up

  # configure the upstream port
  ip addr add 192.0.2.1/30 dev wan

  # create bridge
  ip link add name br0 type bridge

  # add ports to bridge
  ip link set dev lan1 master br0
  ip link set dev lan2 master br0

  # configure the bridge
  ip addr add 192.0.2.129/25 dev br0

  # bring up the bridge
  ip link set dev br0 up

.. _dsa-vlan-configuration:

Configuration without tagging support
-------------------------------------

A minority of switches are not capable to use a taging protocol
(DSA_TAG_PROTO_NONE). These switches can be configured by a VLAN based
configuration.

single port
~~~~~~~~~~~
The configuration can only be set up via VLAN tagging and bridge setup.

.. code-block:: sh

  # tag traffic on CPU port
  ip link add link eth0 name eth0.1 type vlan id 1
  ip link add link eth0 name eth0.2 type vlan id 2
  ip link add link eth0 name eth0.3 type vlan id 3

  # The master interface needs to be brought up before the slave ports.
  ip link set eth0 up
  ip link set eth0.1 up
  ip link set eth0.2 up
  ip link set eth0.3 up

  # bring up the slave interfaces
  ip link set lan1 up
  ip link set lan2 up
  ip link set lan3 up

  # create bridge
  ip link add name br0 type bridge

  # activate VLAN filtering
  ip link set dev br0 type bridge vlan_filtering 1

  # add ports to bridges
  ip link set dev lan1 master br0
  ip link set dev lan2 master br0
  ip link set dev lan3 master br0

  # tag traffic on ports
  bridge vlan add dev lan1 vid 1 pvid untagged
  bridge vlan add dev lan2 vid 2 pvid untagged
  bridge vlan add dev lan3 vid 3 pvid untagged

  # configure the VLANs
  ip addr add 192.0.2.1/30 dev eth0.1
  ip addr add 192.0.2.5/30 dev eth0.2
  ip addr add 192.0.2.9/30 dev eth0.3

  # bring up the bridge devices
  ip link set br0 up


bridge
~~~~~~

.. code-block:: sh

  # tag traffic on CPU port
  ip link add link eth0 name eth0.1 type vlan id 1

  # The master interface needs to be brought up before the slave ports.
  ip link set eth0 up
  ip link set eth0.1 up

  # bring up the slave interfaces
  ip link set lan1 up
  ip link set lan2 up
  ip link set lan3 up

  # create bridge
  ip link add name br0 type bridge

  # activate VLAN filtering
  ip link set dev br0 type bridge vlan_filtering 1

  # add ports to bridge
  ip link set dev lan1 master br0
  ip link set dev lan2 master br0
  ip link set dev lan3 master br0
  ip link set eth0.1 master br0

  # tag traffic on ports
  bridge vlan add dev lan1 vid 1 pvid untagged
  bridge vlan add dev lan2 vid 1 pvid untagged
  bridge vlan add dev lan3 vid 1 pvid untagged

  # configure the bridge
  ip addr add 192.0.2.129/25 dev br0

  # bring up the bridge
  ip link set dev br0 up

gateway
~~~~~~~

.. code-block:: sh

  # tag traffic on CPU port
  ip link add link eth0 name eth0.1 type vlan id 1
  ip link add link eth0 name eth0.2 type vlan id 2

  # The master interface needs to be brought up before the slave ports.
  ip link set eth0 up
  ip link set eth0.1 up
  ip link set eth0.2 up

  # bring up the slave interfaces
  ip link set wan up
  ip link set lan1 up
  ip link set lan2 up

  # create bridge
  ip link add name br0 type bridge

  # activate VLAN filtering
  ip link set dev br0 type bridge vlan_filtering 1

  # add ports to bridges
  ip link set dev wan master br0
  ip link set eth0.1 master br0
  ip link set dev lan1 master br0
  ip link set dev lan2 master br0

  # tag traffic on ports
  bridge vlan add dev lan1 vid 1 pvid untagged
  bridge vlan add dev lan2 vid 1 pvid untagged
  bridge vlan add dev wan vid 2 pvid untagged

  # configure the VLANs
  ip addr add 192.0.2.1/30 dev eth0.2
  ip addr add 192.0.2.129/25 dev br0

  # bring up the bridge devices
  ip link set br0 up
