[libvirt-users] sttic vnet device for guest

Laine Stump laine at laine.org
Mon Oct 31 13:45:37 UTC 2016

On 10/28/2016 05:30 PM, Michal Privoznik wrote:
> On 28.10.2016 14:17, Anton Gorlov wrote:
>> 28.10.2016 23:32, Michal Privoznik пишет:
>> On my host node i using system created bridge. example
>> brctl show br1
>> bridge name     bridge id               STP enabled     interfaces
>> br1             8000.0025907925d3       no              eth1
>>                                                          vnet0
>>                                                          vnet2
>>                                                          vnet3
>> vnetN - guest net adapter, It added to bridge at guest's node started.
>> bridge defined as
>> ==
>> <network>
>> <name>internal</name>
>> <forward mode="bridge"/>
>> <bridge name="br1"/>
>> </network>
>> ==
>> But in guest config xml vnet[0-3] nod defined
>> ===
>>     <interface type='network'>
>>        <mac address='52:54:00:b3:b0:47'/>
>>        <source network='internal'/>
>>        <model type='virtio'/>
>>        <address type='pci' domain='0x0000' bus='0x00' slot='0x03'
>> function='0x0'/>
>>      </interface>
>> ===
> Sure. As I said - it is allocated at domain start up phase. Because
> that's when we know what's the next free device (or name that we can use
> for the device). If you start the domain, with your configuration
> libvirt will create vnetX and plug it into br1. Essentially, target
> device is runtime information, thus not present in config XML.

... but *is* in the status xml (i.e. the output of "visrh dumpxml 
$domain" while the domain is running, and also the xml provided on stdin 
to the qemu and network hooks when they are called).

(also, what Vincent said in his email - names with the prefix "vnet" are 
assumed to be "leftover" from a previous instance of the domain (for 
better or worse) an replaced with an autogenerated name. But if you 
supply a name that doesn't start with "vnet", it will be used).

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