Chapter 18. Virtual Networking
This chapter introduces the concepts needed to create, start, stop, remove, and modify virtual networks with libvirt.
Additional information can be found in the libvirt reference chapter
18.1. Virtual Network Switches
Libvirt virtual networking uses the concept of a virtual network switch. A virtual network switch is a software construct that operates on a host physical machine server, to which virtual machines (guests) connect. The network traffic for a guest is directed through this switch:
Figure 18.1. Virtual network switch with two guests
Linux host physical machine servers represent a virtual network switch as a network interface. When the libvirtd daemon (
libvirtd
) is first installed and started, the default network interface representing the virtual network switch is virbr0
.
This
virbr0
interface can be viewed with the ip
command like any other interface:
$ ip addr show virbr0 3: virbr0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN link/ether 1b:c4:94:cf:fd:17 brd ff:ff:ff:ff:ff:ff inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0