docs/reference/cmdreference/interface/create_interface.rst

.. _interface:

.. toctree::

Create Interfaces Commands
===========================
This section contains those interface commands that are associated to creating an interface:

* `Create Host-Interface`_
* `Create Interface Memif`_
* `Create Loopback Interface`_
* `Create Sub-Interfaces`_

.. note:: For a complete list of CLI Debug commands refer to the Debug CLI section of the `Source Code Documents <https://docs.fd.io/vpp/18.07/clicmd.html>`_ .

Create Host-Interface
++++++++++++++++++++++
Summary/Usage
-------------

create host-interface name <*ifname*> [*hw-addr <*mac-addr*>]

Description
------------

Create a host interface that will attach to a linux AF_PACKET interface, one side of a veth pair.
The veth pair must already exist. Once created, a new host interface will exist in VPP with the name
'host-<*ifname*>', where '<*ifname*>' is the name of the specified veth pair.
Use the `show interface` command to display host interface details.

This command has the following optional parameters:

    hw-addr <*mac-addr*> - Optional ethernet address, can be in either X:X:X:X:X:X unix or X.X.X cisco format

Example Usage
-------------

Example of how to create a host interface tied to one side of an existing linux veth pair named vpp1:

	.. code-block:: console

		vpp# create host-interface name vpp1

		host-vpp1

Once the host interface is created, enable the interface using:

	.. code-block:: console

		vpp# set interface state host-vpp1 up

Declaration and Implementation
-------------------------------

**Declaration:** af_packet_create_command (src/vnet/devices/af_packet/cli.c line 133)

**Implementation:** af_packet_create_command_fn

Create Interface Memif
+++++++++++++++++++++++

Summary/Usage
-------------

create interface memif [id <*id*>] [socket-id <*socket-id*>] [ring-size <*size*>] [buffer-size <*size*>] [hw-addr <*mac-address*>] <master|slave> [rx-queues <*number*>] [tx-queues <*number*>] [mode ip] [secret <*string*>]

Declaration and Implementation
-------------------------------

**Declaration:** memif_create_command (src/plugins/memif/cli.c line 258)

**Implementation:** memif_create_command_fn


Create Loopback Interface
++++++++++++++++++++++++++

Summary/Usage
--------------

create loopback interface [mac <*mac-addr*>] [instance <*instance*>]

Description
------------

Create a loopback interface. Optionally, a MAC Address can be provided. If not provided, de:ad:00:00:00:<*loopId*> will be used.

Example Usage
--------------
The following two command syntaxes are equivalent:

	.. code-block:: console

		vpp# loopback create-interface [mac <*mac-addr*>] [instance <*instance*>]

		vpp# create loopback interface [mac <*mac-addr*>] [instance <*instance*>]

Example of how to create a loopback interface:

	.. code-block:: console

		vpp# create loopback interface

Declaration and Implementation
-------------------------------

**Declaration:** create_loopback_interface_command (src/vnet/ethernet/interface.c line 879)

**Implementation:** create_simulated_ethernet_interfaces


Create Sub-Interfaces
++++++++++++++++++++++

This command is used to add VLAN IDs to interfaces, also known as
subinterfaces. The primary input to this command is the *interface*
and *subId* (subinterface Id) parameters. If no additional VLAN ID is
provide, the VLAN ID is assumed to be the *subId*. The VLAN ID and
*subId* can be different, but this is not recommended.

This command has several variations: 

-  **create sub-interfaces** <*interface*> <*subId*> - Create a subinterface
   to process packets with a given 802.1q VLAN ID (same value as the
   *subId*).
-  **create sub-interfaces** <*interface*> <*subId*> default - Adding the
   *default* parameter indicates that packets with VLAN IDs that do
   not match any other subinterfaces should be sent to this
   subinterface.
-  **create sub-interfaces** <*interface*> <*subId*> untagged - Adding the
   *untagged* parameter indicates that packets no VLAN IDs should be
   sent to this subinterface.
-  **create sub-interfaces** <*interface*> <*subId*>-<*subId*> - Create a
   range of subinterfaces to handle a range of VLAN IDs.
-  **create sub-interfaces** <*interface*> <*subId*> dot1q|dot1ad <*vlanId*>|any
   [exact-match] - Use this command to explicitly specify the outer VLAN ID,
   or to make the VLAN ID different from the *subId*.
-  **create sub-interfaces** <*interface*> <*subId*> dot1q|dot1ad <*vlanId*>|any
   inner-dot1q <*vlanId*>|any [exact-match] - Use this command to
   specify the outer VLAN ID and the inner VLAN ID.

When *dot1q* or *dot1ad* is explicitly entered, subinterfaces can be
configured as either *exact-match* or *non-exact match*. *Non-exact match* is
the CLI default. If *exact-match* is specified, packets must have the
same number of VLAN tags as the configuration. For *non-exact-match*,
packets must at least that number of tags. L3 (routed) interfaces must
be configured as exact-match. L2 interfaces are typically configured as
non-exact-match. If *dot1q* or *dot1ad* is NOT entered, then the
default behavior is *exact-match*.

Use the **show interface** command to display all subinterfaces.

Summary/Usage
-------------

.. code-block:: shell

    create sub-interfaces <interface> {<subId> [default|untagged]} | {<subId>-<subId>} | {<subId> dot1q|dot1ad <vlanId>|any [inner-dot1q <vlanId>|any] [exact-match]}

Example Usage
--------------

Example of how to create a VLAN subinterface 11 to process packets on 802.1q VLAN ID 11:

.. code-block:: console

    vpp# create sub-interfaces GigabitEthernet2/0/0 11

The previous example is shorthand and is equivalent to:

.. code-block:: console

    vpp# create sub-interfaces GigabitEthernet2/0/0 11 dot1q 11 exact-match

Example of how to create a subinterface number that is different from the VLAN ID:

.. code-block:: console

    vpp# create sub-interfaces GigabitEthernet2/0/0 11 dot1q 100

Examples of how to create q-in-q and q-in-any subinterfaces:

.. code-block:: console

    vpp# create sub-interfaces GigabitEthernet2/0/0 11 dot1q 100 inner-dot1q 200
    vpp# create sub-interfaces GigabitEthernet2/0/0 12 dot1q 100 inner-dot1q any

Examples of how to create dot1ad interfaces:

.. code-block:: console

    vpp# create sub-interfaces GigabitEthernet2/0/0 11 dot1ad 11
    vpp# create sub-interfaces GigabitEthernet2/0/0 12 dot1ad 100 inner-dot1q 200

Examples of *exact-match* versus non-exact match. A packet with outer VLAN 100 and inner VLAN 200 would match this interface, because the default is non-exact match:

.. code-block:: console

    vpp# create sub-interfaces GigabitEthernet2/0/0 5 dot1q 100

However, the same packet would NOT match this interface because *exact-match* is specified and only one VLAN is configured, but packet contains two VLANs:

.. code-block:: console

    vpp# create sub-interfaces GigabitEthernet2/0/0 5 dot1q 100 exact-match

Example of how to created a subinterface to process untagged packets:

.. code-block:: console

   vpp# create sub-interfaces GigabitEthernet2/0/0 5 untagged

Example of how to created a subinterface to process any packet with a VLAN ID that does not match any other subinterface:

.. code-block:: console

    vpp# create sub-interfaces GigabitEthernet2/0/0 7 default

When subinterfaces are created, they are in the down state. Example of how to enable a newly created subinterface:

.. code-block:: console

    vpp# set interface GigabitEthernet2/0/0.7 up