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原创最新推荐文章于 2026-04-03 03:03:25 发布 4.3k 阅读 AI 写同款· GEO 优化 ›

兄弟，还在为调API烧钱？TaoToken Coding Plan双Flash模型，月卡39块管饱

立即获取API key

bty：git 提交需要xwindow的办法
unset SSH_ASKPASS

1.在virsh的xml定义中加入channel指定host的socket映射到guest的dev
用virsh启动虚拟机的时候
注意加channel


 <channel type='unix'>  
      <source mode='bind' path='/var/lib/libvirt/qemu/test.agent'/>  
      <target type='virtio' name='com.haoning.spice.0'/>  
      <alias name='channel0'/>  
      <address type='virtio-serial' controller='0' bus='0' port='1'/>  
 </channel>

2.在guest中启动qemu-ga:
yum install qemu-guest-agent qemu-kvm-tools

qemu-ga -v -p /dev/virtio-ports/com.haoning.spice.0

3.在host上使用python连socket或者socat

socat unix-connect:/var/lib/libvirt/qemu/test.agent readline

具体的control.xml


<domain type='kvm' id='12'>
  <name>control</name>
  <uuid>d07d7290-9b1d-f33e-f54a-70a821252410</uuid>
  <memory unit='KiB'>4194304</memory>
  <currentMemory unit='KiB'>4194304</currentMemory>
  <vcpu placement='static'>1</vcpu>
  <os>
    <type arch='x86_64' machine='rhel6.5.0'>hvm</type>
    <boot dev='hd'/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <pae/>
  </features>
  <clock offset='utc'/>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <devices>
    <emulator>/usr/libexec/qemu-kvm</emulator>
    <disk type='file' device='cdrom'>
      <driver name='qemu' type='raw'/>
      <source file='/home/rhel-server-6.5-x86_64-dvd.iso'/>
      <target dev='hdc' bus='ide'/>
      <readonly/>
      <alias name='ide0-1-0'/>
      <address type='drive' controller='0' bus='1' target='0' unit='0'/>
    </disk>
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2' cache='none'/>
      <source file='/home/control.img'/>
      <target dev='vda' bus='virtio'/>
      <alias name='virtio-disk0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
    </disk>
    <controller type='usb' index='0'>
      <alias name='usb0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
    </controller>
    <controller type='ide' index='0'>
      <alias name='ide0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
    </controller>
    <controller type='virtio-serial' index='0'>
      <alias name='virtio-serial0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
    </controller>
    <interface type='bridge'>
      <mac address='52:54:02:a1:90:81'/>
      <source bridge='br0'/>
      <target dev='vnet0'/>
      <model type='virtio'/>
      <alias name='net0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>
    <serial type='pty'>
      <source path='/dev/pts/1'/>
      <target port='0'/>
      <alias name='serial0'/>
    </serial>
    <console type='pty' tty='/dev/pts/1'>
      <source path='/dev/pts/1'/>
      <target type='serial' port='0'/>
      <alias name='serial0'/>
    </console>
    <channel type='unix'>
      <source mode='bind' path='/var/lib/libvirt/qemu/test.agent'/>
      <target type='virtio' name='com.haoning.spice.0'/>
      <alias name='channel0'/>
      <address type='virtio-serial' controller='0' bus='0' port='1'/>
    </channel>
    <input type='mouse' bus='ps2'/>
    <graphics type='vnc' port='5900' autoport='no' listen='0.0.0.0'>
      <listen type='address' address='0.0.0.0'/>
    </graphics>
    <sound model='ich6'>
      <alias name='sound0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
    </sound>
    <video>
      <model type='cirrus' vram='9216' heads='1'/>
      <alias name='video0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
    </video>
    <memballoon model='virtio'>
      <alias name='balloon0'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
    </memballoon>
  </devices>
  <seclabel type='dynamic' model='selinux' relabel='yes'>
    <label>system_u:system_r:svirt_t:s0:c681,c978</label>
    <imagelabel>system_u:object_r:svirt_image_t:s0:c681,c978</imagelabel>
  </seclabel>
</domain>

virsh define control.xml
virsh start control

在guest中
[code="java"]
# qemu-ga -v -p /dev/virtio-ports/com.haoning.spice.0
1437616495.53279: debug: received EOF
1437616495.153410: debug: received EOF
1437616495.253627: debug: received EOF
1437616495.353849: debug: received EOF
1437616495.454057: debug: received EOF
1437616495.554266: debug: received EOF
1437616495.654507: debug: received EOF
1437616495.754719: debug: received EOF
1437616495.854928: debug: received EOF
1437616495.955151: debug: received EOF
1437616496.55375: debug: received EOF
1437616496.155490: debug: received EOF
^C1437616496.170249: debug: received signal num 2, quitting
#
[/code]

[code="java"]
# ls
poll_qemu_guest_agent.py
# cat poll_qemu_guest_agent.py
#! /usr/bin/python

import base64
import json
import select
import socket

#sock_file = "/tmp/foo.sock"
sock_file = "/var/lib/libvirt/qemu/test.agent"

#import pdb;pdb.set_trace()
READ_LEN = 1024
read_file = "/proc/cpuinfo"
send_cmds = [{"execute": "guest-file-open", "arguments": {"path": read_file, "mode": "r"}},
{"execute": "guest-file-read", "arguments": {"handle": None, "count": READ_LEN}},
{"execute": "guest-file-close", "arguments": {"handle": None}}]

serversocket = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
serversocket.connect(sock_file)
serversocket.setblocking(0)

vm_fileno = serversocket.fileno()
instances = {}
instances[vm_fileno] = "instance-000004e8"

epoll = select.epoll()
epoll.register(vm_fileno, select.EPOLLIN | select.EPOLLOUT | select.EPOLLET)

try:
#import ipdb;ipdb.set_trace()
cmd = 0
stop = False
while True:
print '-'*10 + 'start epoll' + '-'*10
events = epoll.poll(1)
for fileno, event in events:
if fileno in instances.keys():# new client is connecting
print 'instance: ' + instances[fileno]
if event & select.EPOLLIN: # new msg is coming in
print "<<<<<<<<<<<recv"
try:
vm_resp = ''
while True:
vm_resp += serversocket.recv(READ_LEN)
except socket.error:
pass

epoll.modify(fileno, select.EPOLLOUT | select.EPOLLET)

try:
vm_resps = vm_resp.split('\n')
ok_resp = None
for resp in vm_resps:
if 'error' not in resp and 'return' in resp:
ok_resp = resp
break
elif 'error' in resp:
print 'error occurs: ', resp
if ok_resp is not None:
resp = json.loads(ok_resp)
else:
print 'no valid data recv'
break
except ValueError:
print 'response content error: ', vm_resp
break

if len(send_cmds) <= cmd:
stop = True
print resp
break
try:
if cmd == 1:
print('+'*10 + 'receive:' + '+'*10 + '\n' + vm_resp)
handle = resp["return"]
send_cmds[cmd]["arguments"]["handle"] = handle
send_cmds[cmd+1]["arguments"]["handle"] = handle
elif cmd == 2:
decoded_file = base64.decodestring(resp["return"]["buf-b64"])
print 'file content:\n', decoded_file
print resp["return"]["count"]
print 'EOF: ', resp["return"]["eof"]
except (KeyError, ValueError, TypeError):
print 'response content error: ', resp

elif event & select.EPOLLOUT: # new msg need send out
print ">>>>>>>>>send"
if len(send_cmds) <= cmd:
print 'no data to send'
break
try:
byteswritten = 0
data = json.dumps(send_cmds[cmd])
while True:
byteswritten += serversocket.send(data[byteswritten:])
if byteswritten == len(data):
print '*'*10 + 'send over' + '*'*10
break
except socket.error:
pass

epoll.modify(fileno, select.EPOLLIN | select.EPOLLET)
cmd += 1

elif event & select.EPOLLHUP: # connect closed
epoll.unregister(serversocket.fileno())
serversocket.close()

print '-'*10 + 'end epoll' + '-'*10 + '\n'
if stop:
print 'stop now'
break
finally:
epoll.unregister(serversocket.fileno())
epoll.close()
serversocket.close()
#
[/code]

用socat调用


socat unix-connect:/tmp/qga.sock readline
 {"execute":"guest-sync", "arguments":{"id":1234}}
 {"return": 1234}

socat参考
[url]http://wiki.qemu.org/Features/QAPI/GuestAgent[/url]
libvirt配置参考
http://wiki.libvirt.org/page/Qemu_guest_agent
其他参考
http://aspirer2004.blog.163.com/blog/static/1067647201352423628885/

参考
http://www.cloudcraft.cn/use-qemu-guest-agent-to-change-openstack-instance-root-password/

已有功能
http://www.cnblogs.com/biangbiang/p/3222458.html


已有功能



目前qga最新版本为1.5.50，linux已经实现下面的所有功能，windows仅支持加*的那些功能：


复制代码

Ø guest-sync-delimited*：宿主机发送一个int数字给qga，qga返回这个数字，并且在后续返回字符串响应中加入ascii码为0xff的字符，其作用是检查宿主机与qga通信的同步状态，主要用在宿主机上多客户端与qga通信的情况下客户端间切换过程的状态同步检查，比如有两个客户端A、B，qga发送给A的响应，由于A已经退出，目前B连接到qga的socket，所以这个响应可能被B收到，如果B连接到socket之后，立即发送该请求给qga，响应中加入了这个同步码就能区分是A的响应还是B的响应；在qga返回宿主机客户端发送的int数字之前，qga返回的所有响应都要忽略；


Ø guest-sync*：与上面相同，只是不在响应中加入0xff字符；


Ø guest-ping*：Ping the guest agent, a non-error return implies success；


Ø guest-get-time*：获取虚拟机时间（返回值为相对于1970-01-01 in UTC，Time in nanoseconds.）；


Ø guest-set-time*：设置虚拟机时间（输入为相对于1970-01-01 in UTC，Time in nanoseconds.）；


Ø guest-info*：返回qga支持的所有命令；


Ø guest-shutdown*：关闭虚拟机（支持halt、powerdown、reboot，默认动作为powerdown）；


Ø guest-file-open：打开虚拟机内的某个文件（返回文件句柄）；


Ø guest-file-close：关闭打开的虚拟机内的文件；


Ø guest-file-read：根据文件句柄读取虚拟机内的文件内容（返回base64格式的文件内容）；


Ø guest-file-write：根据文件句柄写入文件内容到虚拟机内的文件；


Ø guest-file-seek：Seek to a position in the file, as with fseek(), and return the current file position afterward. Also encapsulates ftell()'s functionality, just Set offset=0, whence=SEEK_CUR；


Ø guest-file-flush：Write file changes bufferred in userspace to disk/kernel buffers；


Ø guest-fsfreeze-status：Get guest fsfreeze state. error state indicates；


Ø guest-fsfreeze-freeze：Sync and freeze all freezable, local guest filesystems；


Ø guest-fsfreeze-thaw：Unfreeze all frozen guest filesystems；


Ø guest-fstrim：Discard (or "trim") blocks which are not in use by the filesystem；


Ø guest-suspend-disk*：Suspend guest to disk；


Ø guest-suspend-ram*：Suspend guest to ram；


Ø guest-suspend-hybrid：Save guest state to disk and suspend to ram（This command requires the pm-utils package to be installed in the guest.）；


Ø guest-network-get-interfaces：Get list of guest IP addresses, MAC addresses and netmasks；


Ø guest-get-vcpus：Retrieve the list of the guest's logical processors；


guest-set-vcpus：Attempt to reconfigure (currently: enable/disable) logical processors inside the guest。

参考
http://wiki.qemu.org/Features/QAPI/GuestAgent


 mdroth@illuin:~$ sudo socat unix-connect:/tmp/qga.sock readline
 {"execute":"guest-sync", "arguments":{"id":1234}}
 {"return": 1234}

 {"execute":"guest-ping"}
 {"return": {}}

 {"execute": "guest-info"}
 {"return": {"version": "1.0"}}

 // write "hello world!\n" to /tmp/testqga
 {"execute":"guest-file-open", "arguments":{"path":"/tmp/testqga","mode":"w+"}}
 {"return": 0}
 {"execute":"guest-file-write", "arguments":{"handle":0,"buf-b64":"aGVsbG8gd29ybGQhCg=="}}
 {"return": {"count": 13, "eof": false}}
 {"execute":"guest-file-close", "arguments":{"handle":0}}
 {"return": {}}

 // read back the "hello world!\n" from /tmp/testqga
 {"execute":"guest-file-open", "arguments":{"path":"/tmp/testqga","mode":"r"}}
 {"return": 1}
 {"execute":"guest-file-read", "arguments":{"handle":1,"count":1024}}
 {"return": {"buf-b64": "aGVsbG8gd29ybGQhCg==", "count": 13, "eof": true}}
 {"execute":"guest-file-close","arguments":{"handle":1}}
 {"return": {}}

 // freeze and unfreeze freezable guest filesystems
 {"execute":"guest-fsfreeze-status"}
 {"return": "thawed"}
 {"execute":"guest-fsfreeze-freeze"}
 {"return": 3}
 {"execute":"guest-fsfreeze-status"}
 {"return": "frozen"}
 {"execute":"guest-fsfreeze-thaw"}
 {"return": 3}
 {"execute":"guest-fsfreeze-status"}
 {"return": "thawed"}