Network XML format
This page provides an introduction to the network port XML format. This stores information about the connection between a virtual interface of a virtual domain, and the virtual network it is attached to.
Element and attribute overview ¶
The root element required for all virtual network ports is
named networkport and has no configurable attributes
The network port XML format is available since
5.5.0
General metadata ¶
The first elements provide basic metadata about the virtual network port.
<networkport
<uuid>7ae63b5f-fe96-4af0-a7c3-da04ba1b3f54</uuid>
<owner>
<uuid>06578fc1-c686-46fa-bc2c-220893b466a6</uuid>
<name>myguest<name>
</owner>
<group>webfront<group>
<mac address='52:54:0:7b:35:93'/>
...
-
uuid - The content of the
uuidelement provides a globally unique identifier for the virtual network port. The format must be RFC 4122 compliant, eg3e3fce45-4f53-4fa7-bb32-11f34168b82b. If omitted when defining/creating a new network port, a random UUID is generated. - The
ownernode records the domain object that is the owner of the network port. It contains two child nodes:uuid- The content of the
uuidelement provides a globally unique identifier for the virtual domain. name- The unique name of the virtual domain
-
group - The port group in the virtual network to which the port belongs. Can be omitted if no port groups are defined on the network.
-
mac - The
addressattribute provides the MAC address of the virtual port that will be see by the guest. The MAC address must not start with 0xFE as this byte is reserved for use on the host side of the port.
Common elements ¶
The following elements are common to one or more of the plug types listed later
...
<bandwidth>
<inbound average='1000' peak='5000' floor='200' burst='1024'/>
<outbound average='128' peak='256' burst='256'/>
</bandwidth>
<rxfilters trustGuest='yes'/>
<port isolated='yes'/>
<virtualport type='802.1Qbg'>
<parameters managerid='11' typeid='1193047' typeidversion='2'/>
</virtualport>
...
-
bandwidth - This part of the network port XML provides setting quality of service.
Incoming and outgoing traffic can be shaped independently.
The
bandwidthelement and its child elements are described in the QoS section of the Network XML. In addition theclassIDattribute may exist to provide the ID of the traffic shaping class that is active. -
rxfilters - The
rxfilterselement propertytrustGuestprovides the capability for the host to detect and trust reports from the guest regarding changes to the interface mac address and receive filters by setting the attribute toyes. The default setting for the attribute isnofor security reasons and support depends on the guest network device model as well as the type of connection on the host - currently it is only supported for the virtio device model and for macvtap connections on the host. -
port - Since 6.1.0.
The
portelement propertyisolated, when set toyes(default setting isno) is used to isolate this port's network traffic from other ports on the same network that also have<port isolated='yes'/>. This setting is only supported for emulated network devices connected to a Linux host bridge via a standard tap device. -
virtualport - The
virtualportelement describes metadata that needs to be provided to the underlying network subsystem. It is described in the domain XML interface documentation.
Plugs ¶
The plug element has varying content depending
on the value of the type attribute.
Network ¶
The network plug type refers to a managed virtual
network plug that is based on a traditional software bridge
device privately managed by libvirt.
... <plug type='network' bridge='virbr0'/> ...
The bridge attribute provides the name of the
privately managed bridge device associated with the virtual
network.
Bridge ¶
The bridge plug type refers to an externally
managed traditional software bridge.
... <plug type='bridge' bridge='br2'/> ...
The bridge attribute provides the name of the
externally managed bridge device associated with the virtual
network.
Direct ¶
The direct plug type refers to a connection
directly to a physical network interface.
... <plug type='direct' dev='ens3' mode='vepa'/> ...
The dev attribute provides the name of the
physical network interface to which the port will be
connected. The mode attribute describes
how the connection will be setup and takes the same
values described in the
domain XML.
Host PCI ¶
The hostdev-pci plug type refers to the
passthrough of a physical PCI device rather than emulation.
...
<plug type='hostdev-pci' managed='yes'>
<driver name='vfio'/>
<address domain='0x0001' bus='0x02' slot='0x03' function='0x4'/>
</plug>
...
The managed attribute indicates who is responsible for
managing the PCI device in the host. When set to the value yes
libvirt is responsible for automatically detaching the device from host
drivers and resetting it if needed. If the value is no,
some other party must ensure the device is not attached to any
host drivers.