Using Open vSwitch Bridges

Virtuozzo 6 comes with support for Open vSwitch 1.6 (http://openvswitch.org), multi-layer network switches that function as virtual switches, providing virtual machines and containers with network connectivity. By default, support for Open vSwitch is disabled and Linux bridges are used instead. To start using Open vSwitch bridges on your server, complete these steps:

1. Install the openvswitch package on the server. This package is available in the remote Virtuozzo repository, so you can use the yum install command to install it:

   # yum install openvswitch

2. Configure the openvswitch service to start automatically when the server boots:

   # chkconfig openvswitch on

3. Create a configuration file for the Open vSwitch bridge. Name the file ifcfg-BRIDGE_NAME-NIC_NAME and save it to the /etc/sysconfig/network-scripts directory. For example, the command below creates the configuration file for the br-eth0 bridge that will be attached to the eth0 network card. The easiest way of creating the ifcfg-br-eth0 configuration file is by copying the ifcfg-eth0 file with all its contents:

   # cp /etc/sysconfig/network-scripts/ifcfg-eth0 /etc/sysconfig/network-scripts/ifcfg-br-eth0

4. Configure the parameters in the ifcfg-br-eth0 file:
   • Set the value of the DEVICE parameter to br-eth0.
   • Set the value of the TYPE parameter to OVSBridge.
   • Make sure the SLAVE parameter is present in the file and set to yes.
   • Remove the HWADDR parameter from the file.

   An example of the ifcfg-br-eth0 file is given below:

   DEVICE="br-eth0"

   TYPE="OVSBridge"

   SLAVE="yes"

   BOOTPROTO="dhcp"

   IPV6INIT="no"

   NM_CONTROLLED="yes"

   ONBOOT="yes"

   DEFROUTE="yes"

   PEERDNS="yes"

   PEERROUTES="yes"

   IPV4_FAILURE_FATAL="yes"

5. Configure the /etc/sysconfig/network-scripts/ifcfg-eth0 file:
   • Remove all parameters from the file, except for the following: DEVICE, ONBOOT, TYPE, HWADDR, DEVICETYPE.
   • Set the value of the TYPE parameter to OVSPort.
   • Set the value of the DEVICETYPE parameter to ovs.
   • Add the OVS_BRIDGE parameter to the file and set its value to br-eth0.

   An example of the ifcfg-eth0 file is given below:

   DEVICE="eth0"

   ONBOOT="yes"

   HWADDR="XX:XX:XX:XX:XX:XX"

   TYPE="OVSPort"

   DEVICETYPE="ovs"

   OVS_BRIDGE="br-eth0"

6. Restart the server for the changes to take effect.

After restart, you can check that the br-eth0 bridge has been successfully attached to the eth0 network card by running this command:

# vznetcfg if list

Name Type Network ID Addresses

br-eth0 bridge 10.30.23.246/16,fe80::21c:42ff:fe74:dacf/64,dhcp

veth-eth0.0 veth fe80::a465:a3ff:fe0e:57a6/64

veth-eth0.1 veth Bridged fe80::c79:efff:fe34:301f/64

br1 bridge Bridged fe80::74ef:5dff:fe18:a044/64

br0 bridge Host-Only 10.37.130.2/24,fdb2:2c26:f4e4::1/64

eth0 nic Bridged 10.30.23.246/16,fe80::21c:42ff:fe74:dacf/64

Open vSwitch Restrictions and Limitations

Listed below are Open vSwitch restrictions and limitations:

• It is impossible to use the iptables functionality on physical servers with Open vSwitch bridges enabled.
• Creating and managing private networks with Open vSwitch bridges is not supported. For more information on private networks, see Managing Private Networks.
• Odin Automation for Cloud Infrastructure does not support the "Basic Firewall" feature for servers using Open vSwitch bridges.