libvirt笔记network

虚拟网络可以使用networkLookupByName,networkLookupByUUID,networkLookupByUUIDString和listNetworks这几种方法来发现，可以用下面几种例子展示。

import sys
​import libvirt
​
​conn = None
​try:
​    conn = libvirt.open("qemu:///system")
​except libvirt.libvirtError as e:
​    print(repr(e), file=sys.stderr)
​    exit(1)
​
​# discover all the virtual networks
​networks = conn.listNetworks()
​print('Virtual networks:')
​for network in networks:
​    print('  '+network)
​print()
​
​# lookup the default network by name
​network = conn.networkLookupByName('default')
​print('Virtual network default:')
​print('  name: '+network.name())
​uuid = network.UUIDString()
​print('  UUID: '+uuid)
​print('  bridge: '+network.bridgeName())
​print()
​
​# lookup the default network by name
​network = conn.networkLookupByUUIDString(uuid)
​print('Virtual network default:')
​print('  name: '+network.name())
​print('  UUID: '+network.UUIDString())
​print('  bridge: '+network.bridgeName())
​
​conn.close()
​exit(0)

​import sys
​import libvirt
​
​xml = """
​
​  mynetwork
​  
​  
​  
​    
​      
​    
​  
​"""
​
​conn = None
​try:
​    conn = libvirt.open("qemu:///system")
​except libvirt.libvirtError as e:
​    print(repr(e), file=sys.stderr)
​    exit(1)
​
​# create a persistent virtual network
​network = conn.networkDefineXML(xml)
​if network == None:
​    print('Failed to create a virtual network', file=sys.stderr)
​    exit(1)
​active = network.isActive()
​if active == 1:
​    print('The new persistent virtual network is active')
​else:
​    print('The new persistent virtual network is not active')
​
​network.create() # set the network active
​active = network.isActive()
​if active == 1:
​    print('The new transient virtual network is active')
​else:
​    print('The new transient virtual network is not active')
​
​# now destroy the persistent virtual network
​network.destroy()
​
​# erase the persistent virtual network
​network.undefine()
​
​print()
​
​# create a transient virtual network
​network = conn.networkCreateXML(xml)
​if network == None:
​    print('Failed to define a virtual network', file=sys.stderr)
​    exit(1)
​active = network.isActive()
​if active == 1:
​    print('The new transient virtual network is active')
​else:
​    print('The new transient virtual network is not active')
​
​# now destroy the transient virtual network
​network.destroy()
​
​conn.close()
​exit(0)

在这里插入代码片
```​import sys
​import libvirt
​
​conn = None
​try:
​    conn = libvirt.open("qemu:///system")
​except libvirt.libvirtError as e:
​    print(repr(e), file=sys.stderr)
​    exit(1)
​
​# lookup the default network by name
​network = conn.networkLookupByName('default')
​print('Virtual network default:')
​print('  name: '+network.name())
​print('  UUID: '+network.UUIDString())
​print('  bridge: '+network.bridgeName())
​print('  autostart: '+str(network.autostart()))
​print('  is active: '+str(network.isActive()))
​print('  is persistent: '+str(network.isPersistent()))
​print()
​
​print('Unsetting autostart')
​network.setAutostart(0)
​print('  autostart: '+str(network.autostart()))
​print('Setting autostart')
​network.setAutostart(1)
​print('  autostart: '+str(network.autostart()))
​print()
​
​xml = network.XMLDesc(0)
​print('XML description:')
​print(xml)
​
​conn.close()
​exit(0)