KVM--QEMU Guest Agent（十七）

QEMU Guest Agent概述

QEMU Guest Agent是运行在虚拟机内部的一个守护程序（qemu-guest-agent.service），用它来辅助Hypervisor实现对Guest 虚拟机的管理。QEMU为宿主机和虚拟机提供了一个数据通道（channel），这个通道的两端分别是在虚拟机内看到的串口和在宿主机上看到的unix socket文件。宿主机与虚拟机内的qga通讯就扩展了对虚拟机的控制能力，例如在宿主机上获取虚拟机的ip地址等。

libvrit提供了专门的 virDomainQemuAgentCommand API（对应virsh qemu-agent-command命令）来和qemu-guest-agent通讯，另外libvirt内置api也可以支持qga，例如reboot、shutdown等。

1，编辑虚拟机

virsh edit vm01

2，宿主机上虚拟机xml添加channel

<channel type='unix'>
 <source mode='bind' path='/var/lib/libvirt/qemu/org.qemu.guest_agent.0'/>
 <target type='virtio' name='org.qemu.guest_agent.0'/>
</channel>

3，开启虚拟机

virsh start vm01

4，Linux虚拟机安装qemu-guest-agent

yum install qemu-guest-agent
setenforce 0
systemctl restart qemu-guest-agent.service

5，宿主机上测试

virsh qemu-agent-command vm01 '{"execute":"guest-info"}'
virsh qemu-agent-command vm01 '{"execute":"guest-network-get-interfaces"}'
virsh qemu-agent-command vm01 '{"execute":"guest-ping"}'
virsh  reboot --mode agent vm01
virsh  shutdown --mode agent vm01

Windows virtio-win iso 下载

https://fedorapeople.org/groups/virt/virtio-win/direct-downloads/latest-virtio/

Windows qemu-ga 安装包下载

https://fedorapeople.org/groups/virt/virtio-win/direct-downloads/latest-qemu-ga/

qemu-guest-agent 修改虚拟机用户密码

1.guest-set-user-password

（1）Windows虚拟机安装qemu-ga-x86_64.msi程序

（2）qemu-agent-command 密码必须是base64编码格式

[root@kvm-node1 ~]#  python
Python 2.7.5 (default, Oct 14 2020, 14:45:30) 
[GCC 4.8.5 20150623 (Red Hat 4.8.5-44)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import base64
>>> print base64.b64encode('password') 
cGFzc3dvcmQ=

（3）关闭虚拟机

virsh  destroy win10

（4）修改win10 xml文件添加如下配置

<channel type='unix'>
 <source mode='bind' path='/var/lib/libvirt/qemu/org.qemu.guest_agent.0'/>
 <target type='virtio' name='org.qemu.guest_agent.0'/>
</channel>

（5）启动虚拟机

virsh start win10

（6）qemu-agent-command命令guest-set-user-password修改密码

virsh qemu-agent-command win10 \

'{"execute":"guest-set-user-password","arguments":{"username":"admin","password":"cGFzc3dvcmQ=","crypted":false}}' {"return":{}}

2. virsh set-user-password

virsh set-user-password 修改

virsh set-user-password --domain 6 --user root --password password       
Password set successfully for root in 6

QEMU Guest Agent 支持指令

• guest-exec
• guest-exec-status
• guest-file-close
• guest-file-flush
• guest-file-open
• guest-file-read
• guest-file-seek
• guest-file-write
• guest-fsfreeze-freeze
• guest-fsfreeze-freeze-list
• guest-fsfreeze-status
• guest-fsfreeze-thaw
• guest-fstrim
• guest-get-fsinfo
• guest-get-host-name
• guest-get-memory-block-info
• guest-get-memory-blocks
• guest-get-osinfo
• guest-get-time
• guest-get-timezone
• guest-get-users
• guest-get-vcpus
• guest-info
• guest-network-get-interfaces
• guest-ping
• guest-set-memory-blocks
• guest-set-time
• guest-set-user-password
• guest-set-vcpus
• guest-shutdown
• guest-suspend-disk
• guest-suspend-hybrid
• guest-suspend-ram
• guest-sync
• guest-sync-delimited