5.5. Network Bridges

5.5. Network Bridges

When creating a network with the virtual machine role, a bridge is
created automatically on the port or bond added to the network for
each Oracle VM Server participating in this network. All network packets
generated by the virtual machines are sent to the bridge
configured for the virtual machines’ network. The bridge acts as a
Layer 2 switch, and directs packets to other virtual machines
running on the Oracle VM Server, or to the port or bond, if the packets’
destination is outside of the Oracle VM Server.

Though each virtual machine deployed within a network is usually
assigned an IP address, either static or assigned using DHCP,
there is no need to configure an IP address for the bridge on the
Oracle VM Servers. When configuring your Virtual Machine network, if you
specify an IP address for the port or bond you selected for this
network, it is assigned to the bridge. You can choose not to
assign an IP address to the selected port or bond. In this case,
the bridge does not acquire an address but still functions as a
Layer 2 switch.

Figure 5.3. Network bridge

In Figure 5.3, “Network bridge”, two network ports
are specified for the network with the virtual machine role.
Therefore, these ports should be configured as a bonded interface.
Since this network is configured with the virtual machine role, a
bridge is automatically created on each Oracle VM Server in the network.
Neither the bridge nor the ports in the virtual machine network,
have IP addresses assigned to them, though you may assign IP
addresses if you wish during network creation.

Bridges are only created for networks with the virtual machine
role.