KVM 介绍：libvirt 介绍

dir

fs

netfs

disk

iscsi

logical

scsi

mpath

rbd

sheepdog

gluster
或者

zfs。

<disk type='**' device='**'>。其中：

<disk type='volume' device='disk'>
<driver name='qemu' type='raw'/>
<source pool='blk-pool0' volume='blk-pool0-vol0'/>
<target dev='hdk' bus='ide'/>
</disk>

<disk type='file' snapshot='external'>
<driver name="tap" type="aio" cache="default"/>
<source file='/var/lib/xen/images/fv0' startupPolicy='optional' />
<target dev='hda' bus='ide'/>
</disk>

<disk type='block' device='cdrom'>
<driver name='qemu' type='raw'/>
<target dev='hdd' bus='ide' tray='open'/>
<readonly/>
</disk>

<disk type='network' device='cdrom'>
<driver name='qemu' type='raw'/>
<source protocol="http" name="url_path">
<host name="hostname" port="80"/>
</source>
<target dev='hde' bus='ide' tray='open'/>
<readonly/>
</disk>

<hostdev mode='subsystem' type='usb'> #USB 设备直接分配
<source startupPolicy='optional'>
<vendor id='0x1234'/>
<product id='0xbeef'/>
</source>
<boot order='2'/>
</hostdev>
<hostdev mode='subsystem' type='pci' managed='yes'> #PCI 设备直接分配
<source>
<address domain='0x0000' bus='0x06' slot='0x02' function='0x0'/>
</source>
<boot order='1'/>
<rom bar='on' file='/etc/fake/boot.bin'/>
</hostdev>

有几种 interface 类型：

（1）type = ‘network’ 定义一个连接 Virtual network 的 interface

<devices>
<interface type='network'>
<source network='default'/> #虚拟网络的名称为 ‘default’
</interface>
...
<interface type='network'>
<source network='default' portgroup='engineering'/>
<target dev='vnet7'/>
<mac address="00:11:22:33:44:55"/>
<virtualport>
<parameters instanceid='09b11c53-8b5c-4eeb-8f00-d84eaa0aaa4f'/>
</virtualport>

</interface>
</devices>

#virsh：attach-interface --domain d-2 --type network --source isolatednet1 --mac 52:53:00:4b:75:6f --config

（2）type=‘birdge’ 定义一个 Bridge to LAN（桥接到物理网络）的interface：前提是主机上存在一个 bridge，该 bridge 已经连到物理LAN。

<interface type='bridge'> #连接到 br0
<source bridge='br0'/>
</interface>
<interface type='bridge'> #连接到br1
<source bridge='br1'/>
<target dev='vnet7'/>
<mac address="00:11:22:33:44:55"/>
</interface>
<interface type='bridge'> #连接到 Open vSwithc bridge ovsbr
<source bridge='ovsbr'/>
<virtualport type='openvswitch'>
<parameters profileid='menial' interfaceid='09b11c53-8b5c-4eeb-8f00-d84eaa0aaa4f'/>
</virtualport>
</interface>

#virsh：attach-interface --domain d-2 --type bridge --source virbr0 --mac 52:22:33:44:55:66 --config

（3）type=‘ethernet’ 定义一个使用指定脚本连接到 LAN 的 interface

<devices>
<interface type='ethernet'>
<target dev='vnet7'/>
<script path='/etc/qemu-ifup-mynet'/>
</interface>
</devices>

（4）type=‘direct’ 定义一个直接连到物理网卡（Direct attachment to physical interface）的 interface：需要 Linux macvtap 驱动支持

<interface type='direct' trustGuestRxFilters='no'>
<source dev='eth0' mode='vepa'/>
</interface>

（5）type=‘hostdev’ 定义一个由主机PCI 网卡直接分配（PCI Passthrough）的 interface： 分配主机上的网卡给虚机

<devices>
<interface type='hostdev' managed='yes'>
<driver name='vfio'/>
<source>
<address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
</source>
<mac address='52:54:00:6d:90:02'/>
<virtualport type='802.1Qbh'>
<parameters profileid='finance'/>
</virtualport>
</interface>
</devices>

<bridge name="virbr0" stp="on" delay="5" macTableManager="libvirt"/>
<domain name="example.com" localOnly="no"/>
<forward mode="nat" dev="eth0"/>

<network>
<name>default</name>
<bridge name="virbr0" />
<forward mode="nat"/>
<ip address="192.168.122.1" netmask="255.255.255.0">
<dhcp>
<range start="192.168.122.2" end="192.168.122.254" />
</dhcp>
</ip>
<ip family="ipv6" address="2001:db8:ca2:2::1" prefix="64" />
</network>

<forward mode='nat'><nat><address start='1.2.3.4' end='1.2.3.10'/> </nat> </forward>
<forward mode='nat'><nat><port start='500' end='1000'/></nat></forward>

<network>
<name>local</name>
<bridge name="virbr1" />
<forward mode="route" dev="eth1"/>
<ip address="192.168.122.1" netmask="255.255.255.0">
<dhcp>
<range start="192.168.122.2" end="192.168.122.254" />
</dhcp>
</ip>
<ip family="ipv6" address="2001:db8:ca2:2::1" prefix="64" />
</network>

<network>
<name>host-bridge</name>
<forward mode="bridge"/>
<bridge name="br0"/>
</network>

<forward mode='passthrough'>
<interface dev='eth10'/>
<interface dev='eth11'/>
<interface dev='eth12'/>
<interface dev='eth13'/>
<interface dev='eth14'/>
</forward>

<forward mode='hostdev' managed='yes'>
<driver name='vfio'/>
<address type='pci' domain='0' bus='4' slot='0' function='1'/>
<address type='pci' domain='0' bus='4' slot='0' function='2'/>
<address type='pci' domain='0' bus='4' slot='0' function='3'/>
</forward>