Re: [libvirt-users] generate interface MAC addresses in a particular order

On Sun, Jan 31, 2016 at 8:56 AM, Michal Privoznik <mprivozn(a)redhat.com&gt; wrote: > On 29.01.2016 11:24, Andrei Perietanu wrote: >> Hi all, >> >> I am using libvirt to manage VM on my system; after creating a VM > (default >> no NICs are present in the configuration) you can add any number of >> interfaces to it (as long as they exist on the host). >> To do that, I edit the configuration xlm: >> >> vmXml = self.domain.XMLDesc() >> root = ET.fromstring(vmXml) >> devices = root.find('./devices') >> >> intf = ET.SubElement(devices,'interface') >> intf.set('type', 'bridge') >> src = ET.SubElement(intf,'source') >> src.set('bridge', bIntf) >> model = ET.SubElement(intf,'model') >> model.set('type', 'e1000') >> >> xml = ET.tostring(root) >> self.conn.defineXML(xml) >> >> Now the problem I have is that the MAC addresses are auto-generated and >> because of this there is no way to predict which interface number the > newly >> added interface will map to, on the VM. Ideally, the first added > interface >> is mapped to eth0/0, the second one eth0/1...etc. Since the mappings >> depend on the MAC addresses I figured that is the part I need to have >> control over. >> >> Any ideas? >> > > You can provide mac address too. Only if none was given in the XML > libvirt makes up one. > > Michal > Does libvirt offer a way to generate MAC addresses before adding them to the XML? I may have to generate tens of them and I would not want to reinvent the wheel writing my own MAC address generator.