ganeti.hypervisor.hv_kvm.monitor.QmpConnection

class documentation

class QmpConnection(QemuMonitorSocket):

Constructor: QmpConnection(socket_path)

Connection to the QEMU Monitor using the QEMU Monitor Protocol (QMP).

Method	`__enter__`	Undocumented
Method	`__exit__`	Undocumented
Method	`__init__`	Undocumented
Method	`CheckDiskHotAddSupport`	Check if disk hotplug is possible
Method	`CheckNicHotAddSupport`	Check if NIC hotplug is possible
Method	`connect`	Connects to the QMP monitor.
Method	`ContinueGuestEmulation`	Continue the previously paused guest
Method	`execute_qmp`	Undocumented
Method	`GetCpuInformation`	Retrieve CPU/thread information uses the query-cpus-fast which does not interrupt the guest
Method	`GetFreePCISlot`	Get the first available PCI slot of a running instance.
Method	`GetMigrationStatus`	Retrieve the current migration status
Method	`GetVersion`	Return the QMP/qemu version field
Method	`HasDevice`	Check if a specific device exists or not on a running instance.
Method	`HasDynamicAutoReadOnly`	Check if QEMU uses dynamic auto-read-only for block devices
Method	`HotAddDisk`	Hot-add a disk
Method	`HotAddNic`	Hot-add a NIC
Method	`HotDelDisk`	Hot-del a Disk
Method	`HotDelNic`	Hot-del a NIC
Method	`Powerdown`	Undocumented
Method	`ResizeBlockDevice`	Notify the guest about a disk change.
Method	`SetBalloonMemory`	Undocumented
Method	`SetMigrationCapabilities`	Configure live migration capabilities
Method	`SetMigrationParameters`	Configute live migration parameters
Method	`SetSpicePassword`	Set Spice password of an instance
Method	`SetVNCPassword`	Set VNC password of an instance
Method	`StartMigration`	Start migration of an instance
Method	`StartPostcopyMigration`	Start postcopy-ram migration
Method	`StopGuestEmulation`	Pause the running guest
Constant	`ACTUAL_KEY`	Undocumented
Instance Variable	`package`	Undocumented
Instance Variable	`supported_commands`	Undocumented
Instance Variable	`version`	Undocumented
Method	`_AddFd`	Wrapper around add-fd qmp command
Method	`_filter_hvinfo`	Filter non valid keys of the device's hvinfo (if any).
Method	`_GetBlockDevices`	Get the block devices of a running instance.
Method	`_GetFd`	Wrapper around the getfd qmp command
Method	`_GetPCIDevices`	Get the devices of the first PCI bus of a running instance.
Method	`_GetSupportedCommands`	Update the list of supported commands.
Method	`_HasBlockDevice`	Check if a specific device ID exists among block devices.
Method	`_HasPCIDevice`	Check if a specific device ID exists on the PCI bus.
Method	`_RemoveFdset`	Wrapper around remove-fd qmp command
Constant	`_ACTUAL_KEY`	Undocumented
Constant	`_CAPABILITIES_COMMAND`	Undocumented
Constant	`_DEVICE_ATTRIBUTES`	Undocumented
Constant	`_FIRST_MESSAGE_KEY`	Undocumented
Constant	`_MESSAGE_END_TOKEN`	Undocumented
Constant	`_PACKAGE_KEY`	Undocumented
Constant	`_QEMU_KEY`	Undocumented
Constant	`_QMP_TIMEOUT`	Undocumented
Constant	`_QUERY_COMMANDS`	Undocumented
Constant	`_RETURN_KEY`	Undocumented
Constant	`_VERSION_KEY`	Undocumented
Instance Variable	`_buffer`	Undocumented

Inherited from QemuMonitorSocket:

Method	`get_qmp_response`	Undocumented
Method	`recv_qmp`	Undocumented
Method	`send_qmp`	Undocumented
Method	`wait_for_qmp_event`	Waits for one of the specified events and returns it. If the timeout is reached, returns None.
Method	`_read_buffer`	Undocumented
Constant	`_ARGUMENTS_KEY`	Undocumented
Constant	`_ERROR_CLASS_KEY`	Undocumented
Constant	`_ERROR_DESC_KEY`	Undocumented
Constant	`_ERROR_KEY`	Undocumented
Constant	`_EVENT_KEY`	Undocumented
Constant	`_EXECUTE_KEY`	Undocumented
Constant	`_SEND_END_TOKEN`	Undocumented

Inherited from UnixFileSocketConnection (via QemuMonitorSocket):

Method	`close`	Undocumented
Method	`is_connected`	Undocumented
Method	`recv`	Undocumented
Method	`reset_timeout`	Reset the timeout to self.timeout
Method	`send`	Undocumented
Instance Variable	`sock`	Undocumented
Instance Variable	`socket_path`	Undocumented
Instance Variable	`timeout`	Undocumented
Instance Variable	`_connected`	Undocumented

def __enter__(self): ¶

overrides ganeti.hypervisor.hv_kvm.monitor.UnixFileSocketConnection.__enter__

Undocumented

def __exit__(self, exc_type, exc_value, tb): ¶

overrides ganeti.hypervisor.hv_kvm.monitor.UnixFileSocketConnection.__exit__

Undocumented

def __init__(self, socket_path: str): ¶

overrides ganeti.hypervisor.hv_kvm.monitor.QemuMonitorSocket.__init__

Undocumented

@_ensure_connection
def CheckDiskHotAddSupport(self): ¶

Check if disk hotplug is possible

Hotplug is *not* supported in case the add-fd and blockdev-add qmp commands are not supported

@_ensure_connection
def CheckNicHotAddSupport(self): ¶

Check if NIC hotplug is possible

Hotplug is *not* supported in case the getfd and netdev_add qmp commands are not supported

def connect(self): ¶

overrides ganeti.hypervisor.hv_kvm.monitor.UnixFileSocketConnection.connect

Connects to the QMP monitor.

Connects to the UNIX socket and makes sure that we can actually send and receive data to the kvm instance via QMP.

Raises
`errors.HypervisorError`	when there are communication errors
`errors.ProgrammerError`	when there are data serialization errors

@_ensure_connection
def ContinueGuestEmulation(self): ¶

Continue the previously paused guest

def execute_qmp(self, command: str, arguments: dict = None) -> QmpMessage: ¶

overrides ganeti.hypervisor.hv_kvm.monitor.QemuMonitorSocket.execute_qmp

Undocumented

@_ensure_connection
def GetCpuInformation(self): ¶

Retrieve CPU/thread information uses the query-cpus-fast which does not interrupt the guest

@_ensure_connection
def GetFreePCISlot(self): ¶

Get the first available PCI slot of a running instance.

@_ensure_connection
def GetMigrationStatus(self): ¶

Retrieve the current migration status

@_ensure_connection
def GetVersion(self): ¶

Return the QMP/qemu version field

Accessing the version attribute directly might result in an error since the socket might not be yet connected. This getter method uses the @_ensure_connection decorator to work around this problem.

@_ensure_connection
def HasDevice(self, devid): ¶

Check if a specific device exists or not on a running instance.

It first checks the PCI devices and then the block devices.

@_ensure_connection
def HasDynamicAutoReadOnly(self): ¶

Check if QEMU uses dynamic auto-read-only for block devices

Use QMP schema introspection (QEMU 2.5+) to check for the dynamic-auto-read-only feature.

@_ensure_connection
def HotAddDisk(self, disk, access_mode, cache_writeback, direct, blockdevice): ¶

Hot-add a disk

@_ensure_connection
def HotAddNic(self, nic, devid, tapfds=None, vhostfds=None, features=None, is_chrooted=False): ¶

Hot-add a NIC

First pass the tapfds, then netdev_add and then device_add

@_ensure_connection
def HotDelDisk(self, devid): ¶

Hot-del a Disk

@_ensure_connection
def HotDelNic(self, devid): ¶

Hot-del a NIC

@_ensure_connection
def Powerdown(self): ¶

Undocumented

@_ensure_connection
def ResizeBlockDevice(self, disk_id: str, new_size: int): ¶

Notify the guest about a disk change.

@_ensure_connection
def SetBalloonMemory(self, memory): ¶

Undocumented

@_ensure_connection
def SetMigrationCapabilities(self, capabilities, state): ¶

Configure live migration capabilities

@_ensure_connection
def SetMigrationParameters(self, max_bandwidth, downtime_limit): ¶

Configute live migration parameters

@_ensure_connection
def SetSpicePassword(self, spice_pwd): ¶

Set Spice password of an instance

@_ensure_connection
def SetVNCPassword(self, vnc_pwd): ¶

Set VNC password of an instance

@_ensure_connection
def StartMigration(self, target, port): ¶

Start migration of an instance

@_ensure_connection
def StartPostcopyMigration(self): ¶

Start postcopy-ram migration

@_ensure_connection
def StopGuestEmulation(self): ¶

Pause the running guest

ACTUAL_KEY: str = ¶

Undocumented

Value

'actual'

package = ¶

Undocumented

supported_commands = ¶

Undocumented

version = ¶

Undocumented

def _AddFd(self, fd): ¶

Wrapper around add-fd qmp command

Send fd to a running process via SCM_RIGHTS and then add-fd qmp command to add it to an fdset so that it can be used later by disk hotplugging.

Parameters
fd:int	The file descriptor to pass
Returns
The fdset ID that the fd has been added to
Raises
`errors.HypervisorError`	If add-fd fails for some reason

def _filter_hvinfo(self, hvinfo): ¶

Filter non valid keys of the device's hvinfo (if any).

def _GetBlockDevices(self): ¶

Get the block devices of a running instance.

The query-block QMP command returns a list of dictionaries including information for each virtual disk. For example:

[{"device": "disk-049f140d", "inserted": {"file": ..., "image": ...}}]

Returns
list of dicts	Info about the virtual disks of the instance.

def _GetFd(self, fd, fdname): ¶

Wrapper around the getfd qmp command

Send an fd to a running process via SCM_RIGHTS and then use the getfd qmp command to name it properly so that it can be used later by NIC hotplugging.

Parameters
fd:int	The file descriptor to pass
fdname	Undocumented
Raises
`errors.HypervisorError`	If getfd fails for some reason

def _GetPCIDevices(self): ¶

Get the devices of the first PCI bus of a running instance.

def _GetSupportedCommands(self): ¶

Update the list of supported commands.

def _HasBlockDevice(self, devid): ¶

Check if a specific device ID exists among block devices.

def _HasPCIDevice(self, devid): ¶

Check if a specific device ID exists on the PCI bus.

def _RemoveFdset(self, fdset): ¶

Wrapper around remove-fd qmp command

Remove the file descriptor previously passed. After qemu has dup'd the fd (e.g. during disk hotplug), it can be safely removed.

_ACTUAL_KEY: str = ¶

Undocumented

Value

'actual'

_CAPABILITIES_COMMAND: str = ¶

Undocumented

Value

'qmp_capabilities'

_DEVICE_ATTRIBUTES: list[str] = ¶

Undocumented

Value

['driver', 'id', 'bus', 'addr', 'channel', 'scsi-id', 'lun']

_FIRST_MESSAGE_KEY: str = ¶

Undocumented

Value

'QMP'

_MESSAGE_END_TOKEN: bytes = ¶

overrides ganeti.hypervisor.hv_kvm.monitor.QemuMonitorSocket._MESSAGE_END_TOKEN

Undocumented

Value

b'''\r
'''

_PACKAGE_KEY: str = ¶

Undocumented

Value

'package'

_QEMU_KEY: str = ¶

Undocumented

Value

'qemu'

_QMP_TIMEOUT: int = ¶

Undocumented

Value

_QUERY_COMMANDS: str = ¶

Undocumented

Value

'query-commands'

_RETURN_KEY: str = ¶

overrides ganeti.hypervisor.hv_kvm.monitor.QemuMonitorSocket._RETURN_KEY

Undocumented

Value

'return'

_VERSION_KEY: str = ¶

Undocumented

Value

'version'

_buffer: bytes = ¶

overrides ganeti.hypervisor.hv_kvm.monitor.QemuMonitorSocket._buffer

Undocumented