管理KVM虚拟机
工具：libvirt
介绍：Libvirt 库是一种实现 Linux 虚拟化功能的 Linux® API，它支持各种虚拟机监控程序，包括 Xen 和 KVM，以及 QEMU 和用于其他操作系统的一些虚拟产品。
工作原理如下图
配置文件
KVM创建的虚拟机配置文件路径: /etc/libvirt/qemu，它是xml后缀文件，如之前我们创建的 CentOS-7-X86_64，它的配置文件是CentOS-7-X86_64.xml
备注：这个文件不能使用vi、vim命令进行修改，可以通过命令virsh edit CentOS-7-X86_64修改。
配置文件样例说明：
1 <domain type='kvm'> 2 <name>CentOS-7-X86_64</name> 名称 3 <uuid>ae53ced4-573c-4de0-9bd9-0852451b8573</uuid> 唯一 4 <memory unit='KiB'>2097152</memory> 内存 5 <currentMemory unit='KiB'>2097152</currentMemory> 当前内存 6 <vcpu placement='static'>1</vcpu> CPU 7 <os> 8 <type arch='x86_64' machine='pc-i440fx-rhel7.0.0'>hvm</type> hvm表示硬件虚拟机 9 <boot dev='hd'/> 启动硬盘 10 </os> 11 <features> 12 <acpi/> 13 <apic/> 14 </features> 15 <cpu mode='custom' match='exact'> 16 <model fallback='allow'>Broadwell-noTSX</model> 17 </cpu> 18 <clock offset='utc'> 19 <timer name='rtc' tickpolicy='catchup'/> 20 <timer name='pit' tickpolicy='delay'/> 21 <timer name='hpet' present='no'/> 22 </clock> 23 <on_poweroff>destroy</on_poweroff> 24 <on_reboot>restart</on_reboot> 25 <on_crash>restart</on_crash> 26 <pm> 27 <suspend-to-mem enabled='no'/> 28 <suspend-to-disk enabled='no'/> 29 </pm> 30 <devices> 31 <emulator>/usr/libexec/qemu-kvm</emulator> 32 <disk type='file' device='disk'> 硬盘 33 <driver name='qemu' type='raw'/> 34 <source file='/opt/CentOS-7-x86_64.raw'/> 35 <target dev='vda' bus='virtio'/> 36 <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/> 37 </disk> 38 <disk type='file' device='cdrom'> 39 <driver name='qemu' type='raw'/> 40 <target dev='hda' bus='ide'/> 41 <readonly/> 42 <address type='drive' controller='0' bus='0' target='0' unit='0'/> 43 </disk> 44 <controller type='usb' index='0' model='ich9-ehci1'> 45 <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x7'/> 46 </controller> 47 <controller type='usb' index='0' model='ich9-uhci1'> 48 <master startport='0'/> 49 <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0' multifunction='on'/> 50 </controller> 51 <controller type='usb' index='0' model='ich9-uhci2'> 52 <master startport='2'/> 53 <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x1'/> 54 </controller> 55 <controller type='usb' index='0' model='ich9-uhci3'> 56 <master startport='4'/> 57 <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x2'/> 58 </controller> 59 <controller type='pci' index='0' model='pci-root'/> 60 <controller type='ide' index='0'> 61 <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/> 62 </controller> 63 <controller type='virtio-serial' index='0'> 64 <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> 65 </controller> 66 <interface type='network'> 网络 67 <mac address='52:54:00:d0:dd:c9'/> 68 <source network='default'/> 69 <model type='virtio'/> 70 <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> 71 </interface> 72 <serial type='pty'> 73 <target port='0'/> 74 </serial> 75 <console type='pty'> 76 <target type='serial' port='0'/> 77 </console> 78 <channel type='unix'> 79 <target type='virtio' name='org.qemu.guest_agent.0'/> 80 <address type='virtio-serial' controller='0' bus='0' port='1'/> 81 </channel> 82 <input type='tablet' bus='usb'> 83 <address type='usb' bus='0' port='1'/> 84 </input> 85 <input type='mouse' bus='ps2'/> 86 <input type='keyboard' bus='ps2'/> 87 <graphics type='vnc' port='-1' autoport='yes' listen='0.0.0.0'> 88 <listen type='address' address='0.0.0.0'/> 89 </graphics> 90 <video> 91 <model type='cirrus' vram='16384' heads='1' primary='yes'/> 92 <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/> 93 </video> 94 <memballoon model='virtio'> 95 <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/> 96 </memballoon> 97 </devices> 98 </domain>