openflowd: Update for changes to dpif and netdev.

[ovs.git] / INSTALL.userspace

              Using Open vSwitch without kernel support
              =========================================

Open vSwitch can operate, at a cost in performance, entirely in
userspace, without assistance from a kernel module.  This file
explains how to install Open vSwitch in such a mode.

The userspace-only mode of Open vSwitch is considered experimental.
It has not been thoroughly tested.

This version of Open vSwitch should be built manually with "configure"
and "make".  Debian packaging for Open vSwitch is also included, but
it has not been recently tested, and so Debian packages are not a
recommended way to use this version of Open vSwitch.

Building and Installing
-----------------------

The requirements and procedure for building, installing, and
configuring Open vSwitch are the same as those given in INSTALL.Linux.
You may omit configuring, building, and installing the kernel module,
and the related requirements.

On Linux, the userspace switch additionally requires the kernel
TUN/TAP driver to be available, either built into the kernel or loaded
as a module.  If you are not sure, check for a directory named
/sys/class/misc/tun.  If it does not exist, then attempt to load the
module with "modprobe tun".

The tun device must also exist as /dev/net/tun.  If it does not exist,
then create /dev/net (if necessary) with "mkdir /dev/net", then create
/dev/net/tun with "mknod /dev/net/tun c 10 200".

Using the Userspace Datapath with ovs-vswitchd
----------------------------------------------

To use ovs-vswitchd in userspace mode, give the bridge a name that
begins with "netdev:" in the configuration file.  For example:

    bridge.netdev:br0.port=eth0
    bridge.netdev:br0.port=eth1
    bridge.netdev:br0.port=eth2

ovs-vswitchd will create a TAP device as the bridge's local interface,
named the same as the bridge minus the "netdev:" prefix, as well as
for each configured internal interface.

Using the Userspace Datapath with ovs-openflowd
-----------------------------------------------

To use ovs-openflowd in userspace mode, specify a datapath name that
begins with "netdev:", and specify --ports with the names of the ports
that should be included in the datapath as argument.  For example:

    ovs-openflowd netdev:br0 --ports=eth0,eth1,eth2

ovs-openflowd will create a TAP device as the bridge's local
interface, named the same as the bridge minus the "netdev:" prefix.

Bug Reporting
-------------

Please report problems to bugs@openvswitch.org.