[zz]kvm-libvirt的使用：创建虚拟机与快照

1.创建域(虚拟机)：包括Volume和描述硬件配置的xml

//前端与节点建立连接

Connect conn=new Connect("qemu+ssh://root@192.168.69/system",false);

//根据xml描述创建新虚拟机并启动

SAXReader reader = new SAXReader();

Document docu =<span style="white-space:pre"> </span>reader.read(new File("/domain.xml"));

String xmlDesc=docu.asXML();

Domain domain=conn.domainCreateXML(xmlDesc, 0);

domain.resume();

Connect con=new Connect("");

//根据存储池的名字获得StoragePool

StoragePool pool=con.storagePoolLookupByName("default");

SAXReader reader=new SAXReader();

Document docu=reader.read(new File("/volume.xml"));

StorageVol vol=pool.storageVolCreateXML(docu.asXML(), 0);

Connect con=new Connect("");
//根据存储池的名字获得StoragePool
StoragePool pool=con.storagePoolLookupByName("default");
SAXReader reader=new SAXReader();
Document docu=reader.read(new File("/volume.xml"));
StorageVol vol=pool.storageVolCreateXML(docu.asXML(), 0);

记录下vol的存储地址，赋值到域的配置文件中即可。

删除vol

StorageVol vol=pool.storageVolLookupByName(volName);

vol.delete(0);

//前端与节点建立连接

Connect conn1=new Connect("qemu+ssh://root@192.168.82.70/system",false);

//根据域的uuid-unique id（在生成域时，libvirt自动分配唯一的uuid），返回域。

String uuid="";

Domain domain=conn1.domainLookupByUUIDString(uuid);

Connect conn2=new Connect("qemu+ssh://root@192.168.82.71/system",false);

/*

* 把域从当前主机迁移到目的主机

* Domain migrate(Connect dconn, long flags, String dname, String uri, long bandwidth)

* dconn:目的主机

* dname:可选，重命名域在目的机的名字

* uri:可选，目的机ip

* bandwidth:迁移带宽，Mbps

*/

domain.migrate(conn2, 1, null, null, 5);

//销毁域

domain.destroy();

//前端与节点建立连接
Connect conn1=new Connect("qemu+ssh://root@192.168.82.70/system",false);
//根据域的uuid-unique id（在生成域时，libvirt自动分配唯一的uuid），返回域。
String uuid="";
Domain domain=conn1.domainLookupByUUIDString(uuid);
Connect conn2=new Connect("qemu+ssh://root@192.168.82.71/system",false);
/*
* 把域从当前主机迁移到目的主机
* Domain migrate(Connect dconn, long flags, String dname, String uri, long bandwidth)
* dconn:目的主机
* dname:可选，重命名域在目的机的名字
* uri:可选，目的机ip
* bandwidth:迁移带宽，Mbps
*/
domain.migrate(conn2, 1, null, null, 5);
//销毁域
domain.destroy();

补：域的名字、id等信息都在xml配置描述里定义。对于xml文件的操作使用dom4j。

标准domain.xml

<?xml version="1.0" encoding="UTF-8"?>

<domain type='kvm'>

<name>test</name>

<memory>524288</memory>

<currentMemory>524288</currentMemory>

<vcpu>1</vcpu>

<os>

<type arch='x86_64' machine='pc-0.14'>hvm</type>

<boot dev='hd'/>

<bootmenu enable='no'/>

</os>

<features>

<acpi/>

<apic/>

<pae/>

</features>

<clock offset='localtime'/>

<on_poweroff>destroy</on_poweroff>

<on_reboot>restart</on_reboot>

<on_crash>restart</on_crash>

<devices>

<emulator>/usr/bin/qemu-kvm</emulator>

<disk type='file' device='disk'>

<driver name='qemu' type='qcow2'/>

<source file='/var/lib/libvirt/images/test.img'/><!--运行的镜像-->

<target dev='vda' bus='virtio'/>

<address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>

</disk>

<interface type='network'>

<mac address='52:54:00:19:25:7b'/>

<source network='default'/>

<model type='virtio'/>

<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>

</interface>

<serial type='pty'>

<target port='0'/>

</serial>

<console type='pty'>

<target type='serial' port='0'/>

</console>

<input type='tablet' bus='usb'/>

<input type='mouse' bus='ps2'/>

<graphics type='vnc' port='5910' autoport='no' listen='0.0.0.0'/>

<sound model='ac97'>

<address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>

</sound>

<video>

<model type='cirrus' vram='9216' heads='1'/>

<address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>

</video>

<memballoon model='virtio'>

<address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>

</memballoon>

</devices>

</domain>

<?xml version="1.0" encoding="UTF-8"?>

<volume>

<name></name>

<key>/var/lib/libvirt/images/temp.ss</key>

<source>

</source>

<capacity>8589934592</capacity>

<allocation>139264</allocation>

<target>

<path>/var/lib/libvirt/images/temp.ss</path> <!--新卷的地址-->

<format type='qcow2'/>

<permissions>

<mode>0600</mode>

<owner>0</owner>

<group>0</group>

</permissions>

</target>

<backingStore>

<path>/var/lib/libvirt/images/WinXP.img</path><!--关联的镜像-->

<format type='qcow2'/>

<permissions>

<mode>0600</mode>

<owner>107</owner>

<group>107</group>

</permissions>

</backingStore>

</volume>

<?xml version="1.0" encoding="UTF-8"?>
<volume>
<name></name>
<key>/var/lib/libvirt/images/temp.ss</key>
<source>
</source>
<capacity>8589934592</capacity>
<allocation>139264</allocation>
<target>
<path>/var/lib/libvirt/images/temp.ss</path> <!--新卷的地址-->
<format type='qcow2'/>
<permissions>
<mode>0600</mode>
<owner>0</owner>
<group>0</group>
</permissions>
</target>
<backingStore>
<path>/var/lib/libvirt/images/WinXP.img</path><!--关联的镜像-->
<format type='qcow2'/>
<permissions>
<mode>0600</mode>
<owner>107</owner>
<group>107</group>
</permissions>
</backingStore>
</volume>

补：dom4j使用示例

SAXReader reader = new SAXReader();

Document docu = reader.read(new File("/domain.xml"));

//更改元素的属性值

Element graphics=docu.getRootElement().element("devices").element("graphics");

Attribute attrPort=graphics.attribute("port");

attrPort.setText(getPort());

//更改元素值

Element nameEle=docu.getRootElement().element("name");

nameEle.setText("new name");

//以字符串形式返回xml

String docXmlText=docu.asXML();