ganeti.hypervisor.hv_xen.XenHypervisor

class documentation

class XenHypervisor(hv_base.BaseHypervisor):

Known subclasses: ganeti.hypervisor.hv_xen.XenHvmHypervisor, ganeti.hypervisor.hv_xen.XenPvmHypervisor

Xen generic hypervisor interface

This is the Xen base class used for both Xen PVM and HVM. It contains all the functionality that is identical for both.

Class Method	`GetInstanceConsole`	Return a command for connecting to the console of an instance.
Static Method	`VersionsSafeForMigration`	Decide if migration is likely to suceed for hypervisor versions.
Method	`__init__`	Undocumented
Method	`AcceptInstance`	Prepare to accept an instance.
Method	`BalloonInstanceMemory`	Balloon an instance memory to a certain value.
Method	`FinalizeMigrationDst`	Finalize an instance migration.
Method	`FinalizeMigrationSource`	Finalize the instance migration on the source node.
Method	`GetAllInstancesInfo`	Get properties of all instances.
Method	`GetInstanceInfo`	Get instance properties.
Method	`GetMigrationStatus`	Get the migration status
Method	`GetNodeInfo`	Return information about the node.
Method	`ListInstances`	Get the list of running instances.
Method	`MigrateInstance`	Migrate an instance to a target node.
Method	`MigrationInfo`	Get instance information to perform a migration.
Method	`PowercycleNode`	Xen-specific powercycle.
Method	`RebootInstance`	Reboot an instance.
Method	`RestoreInstance`	Fixup running instance's state.
Method	`StartInstance`	Start an instance.
Method	`StopInstance`	Stop an instance.
Method	`Verify`	Verify the hypervisor.
Method	`VerifyInstance`	Verify if running instance (configuration) is in correct state.
Constant	`ANCILLARY_FILES`	Undocumented
Constant	`ANCILLARY_FILES_OPT`	Undocumented
Constant	`CAN_MIGRATE`	Undocumented
Constant	`REBOOT_RETRY_COUNT`	Undocumented
Constant	`REBOOT_RETRY_INTERVAL`	Undocumented
Class Method	`_EnsureDirs`	Makes sure that the directories needed by the hypervisor exist.
Class Method	`_GetConfig`	Build Xen configuration for an instance.
Class Method	`_InstanceMigrationPidfile`	Returns the name of the pid file for a socat process used to migrate.
Class Method	`_InstanceNICDir`	Returns the directory holding the tap device files for a given instance.
Class Method	`_InstanceNICFile`	Returns the name of the file containing the tap device for a given NIC
Class Method	`_KillMigrationDaemon`	Kills the migration daemon if present.
Class Method	`_WriteNICInfoFile`	Write the Xen config file for the instance.
Method	`_CheckToolstackXlConfigured`	Checks whether xl is enabled on an xl-capable node.
Method	`_ConfigFileName`	Get the config file name for an instance.
Method	`_DestroyInstance`	Destroy an instance if the instance exists.
Method	`_DestroyInstanceIfAlive`	Undocumented
Method	`_GetInstanceList`	Wrapper around module level `_GetAllInstanceList`.
Method	`_MakeConfigFile`	Gather configuration details and write to disk.
Method	`_MigrateInstance`	Migrate an instance to a target node.
Method	`_ReadConfigFile`	Returns the contents of the instance config file.
Method	`_RemoveConfigFile`	Remove the xen configuration file.
Method	`_RenameInstance`	Rename an instance (domain).
Method	`_RunXen`	Wrapper around `utils.process.RunCmd` to run Xen command.
Method	`_ShutdownInstance`	Shutdown an instance if the instance is running.
Method	`_StashConfigFile`	Move the Xen config file to the log directory and return its new path.
Method	`_StopInstance`	Stop an instance.
Method	`_WriteConfigFile`	Write the Xen config file for the instance.
Method	`_WriteNicConfig`	Undocumented
Constant	`_DIRS`	Undocumented
Constant	`_INSTANCE_LIST_DELAYS`	Undocumented
Constant	`_INSTANCE_LIST_TIMEOUT`	Undocumented
Constant	`_MIGRATION_DIR`	Undocumented
Constant	`_NICS_DIR`	Undocumented
Constant	`_ROOT_DIR`	Undocumented
Instance Variable	`_cfgdir`	Undocumented
Instance Variable	`_cmd`	Undocumented
Instance Variable	`_run_cmd_fn`	Undocumented

Inherited from BaseHypervisor:

Class Method	`CheckParameterSyntax`	Check the given parameters for validity.
Class Method	`GetAncillaryFiles`	Return a list of ancillary files to be copied to all nodes as ancillary configuration files.
Class Method	`LinuxPowercycle`	Linux-specific powercycle method.
Class Method	`ValidateParameters`	Check the given parameters for validity.
Static Method	`GetLinuxNodeInfo`	For linux systems, return actual OS information.
Method	`CleanupInstance`	Cleanup after a stopped instance
Method	`HotAddDevice`	Hot-add a device.
Method	`HotDelDevice`	Hot-del a device.
Method	`HotModDevice`	Hot-mod a device.
Method	`HotplugSupported`	Checks if hotplug is supported.
Method	`VerifyHotplugSupport`	Verifies that hotplug is supported.
Constant	`PARAMETERS`	a dict of parameter name: check type; the check type is a five-tuple containing:
Class Method	`_IsParamValueUnspecified`	Check if the parameter value is a kind of value meaning unspecified.
Static Method	`_FormatVerifyResults`	Formats the verification results, given a list of errors.
Method	`_InstanceStartupMemory`	Get the correct startup memory for an instance

@classmethod
def GetInstanceConsole(cls, instance, primary_node, node_group, hvparams, beparams): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.GetInstanceConsole

Return a command for connecting to the console of an instance.

@staticmethod
def VersionsSafeForMigration(src, target): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.VersionsSafeForMigration

Decide if migration is likely to suceed for hypervisor versions.

Given two versions of a hypervisor, give a guess whether live migration from the one version to the other version is likely to succeed. For Xen, the heuristics is, that an increase by one on the second digit is OK. This fits with the current numbering scheme.

Parameters
src:list or tuple	Undocumented
target:list or tuple	Undocumented
Returns
bool	Undocumented

def __init__(self, _cfgdir=None, _run_cmd_fn=None, _cmd=None): ¶

Undocumented

def AcceptInstance(self, instance, info, target): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.AcceptInstance

Prepare to accept an instance.

Parameters
instance:`objects.Instance`	instance to be accepted
info:string	content of the xen config file on the source node
target:string	target host (usually ip), on this node

def BalloonInstanceMemory(self, instance, mem): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.BalloonInstanceMemory

Balloon an instance memory to a certain value.

Parameters
instance:`objects.Instance`	instance to be accepted
mem:int	actual memory size to use for instance runtime

def FinalizeMigrationDst(self, instance, config, success): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.FinalizeMigrationDst

Finalize an instance migration.

Write a config file if the instance is running on the destination node regardles if we think the migration succeeded or not. This will cover cases, when the migration succeeded but due to a timeout on the source node we think it failed. If we think the migration failed and there is an unstarted domain, clean it up.

Parameters
instance:`objects.Instance`	instance whose migration is being finalized
config:string	content of the xen config file from the source node
success:boolean	whether the master node thinks the migration succeeded

def FinalizeMigrationSource(self, instance, success, _): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.FinalizeMigrationSource

Finalize the instance migration on the source node.

Parameters
instance:`objects.Instance`	the instance that was migrated
success:bool	whether the master thinks the migration succeeded
_	Undocumented

def GetAllInstancesInfo(self, hvparams=None): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.GetAllInstancesInfo

Get properties of all instances.

Parameters
hvparams:dict of strings	hypervisor parameters
Returns
(string, string, int, int, HypervisorInstanceState, int)	list of tuples (name, id, memory, vcpus, state, times)

def GetInstanceInfo(self, instance_name, hvparams=None): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.GetInstanceInfo

Get instance properties.

Parameters
instance_name:string	the instance name
hvparams:dict of strings	the instance's hypervisor params
Returns
tuple (name, id, memory, vcpus, stat, times)

def GetMigrationStatus(self, instance): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.GetMigrationStatus

Get the migration status

As MigrateInstance for Xen is still blocking, if this method is called it means that MigrateInstance has completed successfully. So we can safely assume that the migration was successful and notify this fact to the client.

Parameters
instance:`objects.Instance`	the instance that is being migrated
Returns
`objects.MigrationStatus`	the status of the current migration (one of `constants.HV_MIGRATION_VALID_STATUSES`), plus any additional progress info that can be retrieved from the hypervisor

def GetNodeInfo(self, hvparams=None): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.GetNodeInfo

Return information about the node.

See Also
`_GetNodeInfo` and `_ParseNodeInfo`

def ListInstances(self, hvparams=None): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.ListInstances

Get the list of running instances.

Parameters
hvparams:dict of strings	the instance's hypervisor params
Returns
list of strings	names of running instances

def MigrateInstance(self, _cluster_name, instance, target, live): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.MigrateInstance

Migrate an instance to a target node.

The migration will not be attempted if the instance is not currently running.

Parameters
_cluster_name	Undocumented
instance:`objects.Instance`	the instance to be migrated
target:string	ip address of the target node
live:boolean	perform a live migration

def MigrationInfo(self, instance): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.MigrationInfo

Get instance information to perform a migration.

Parameters
instance:`objects.Instance`	instance to be migrated
Returns
string	content of the xen config file

def PowercycleNode(self, hvparams=None): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.PowercycleNode

Xen-specific powercycle.

This first does a Linux reboot (which triggers automatically a Xen reboot), and if that fails it tries to do a Xen reboot. The reason we don't try a Xen reboot first is that the xen reboot launches an external command which connects to the Xen hypervisor, and that won't work in case the root filesystem is broken and/or the xend daemon is not working.

Parameters
hvparams:dict of strings	hypervisor params to be used on this node

def RebootInstance(self, instance): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.RebootInstance

Reboot an instance.

def RestoreInstance(self, instance, block_devices): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.RestoreInstance

Fixup running instance's state.

Parameters
instance:`objects.Instance`	instance to restore
block_devices:list of tuples (disk_object, link_name, drive_uri)	blockdevices assigned to this instance

def StartInstance(self, instance, block_devices, startup_paused): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.StartInstance

Start an instance.

Parameters
instance:`objects.Instance`	instance to start
block_devices: list of tuples (cfdev, rldev) cfdev: dict containing ganeti config disk part rldev: ganeti.block.bdev.BlockDev object	blockdevices assigned to this instance
startup_paused:bool	if instance should be paused at startup

def StopInstance(self, instance, force=False, retry=False, name=None, timeout=None): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.StopInstance

Stop an instance.

A soft shutdown can be interrupted. A hard shutdown tries forever.

def Verify(self, hvparams=None): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.Verify

Verify the hypervisor.

For Xen, this verifies that the XL toolstack is present and functional

Parameters
hvparams:dict of strings	hypervisor parameters to be verified against
Returns
Problem description if something is wrong, `None` otherwise

def VerifyInstance(self, instance): ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.VerifyInstance

Verify if running instance (configuration) is in correct state.

Parameters
instance:`objects.Instance`	instance to verify
Returns
bool, if instance in correct state

ANCILLARY_FILES = ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.ANCILLARY_FILES

overridden in ganeti.hypervisor.hv_xen.XenHvmHypervisor

Undocumented

Value

[XL_CONFIG_FILE, VIF_BRIDGE_SCRIPT]

ANCILLARY_FILES_OPT = ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.ANCILLARY_FILES_OPT

overridden in ganeti.hypervisor.hv_xen.XenHvmHypervisor

Undocumented

Value

[XL_CONFIG_FILE]

CAN_MIGRATE: bool = ¶

overrides ganeti.hypervisor.hv_base.BaseHypervisor.CAN_MIGRATE

Undocumented

Value

True

REBOOT_RETRY_COUNT: int = ¶

Undocumented

Value

REBOOT_RETRY_INTERVAL: int = ¶

Undocumented

Value

@classmethod
def _EnsureDirs(cls, extra_dirs=None): ¶

Makes sure that the directories needed by the hypervisor exist.

Parameters
extra_dirs:list of string or None	Additional directories which ought to exist.

@classmethod
def _GetConfig(cls, instance, startup_memory, block_devices): ¶

overridden in ganeti.hypervisor.hv_xen.XenHvmHypervisor, ganeti.hypervisor.hv_xen.XenPvmHypervisor

Build Xen configuration for an instance.

@classmethod
def _InstanceMigrationPidfile(cls, _instance_name): ¶

Returns the name of the pid file for a socat process used to migrate.

@classmethod
def _InstanceNICDir(cls, instance_name): ¶

Returns the directory holding the tap device files for a given instance.

@classmethod
def _InstanceNICFile(cls, instance_name, seq): ¶

Returns the name of the file containing the tap device for a given NIC

@classmethod
def _KillMigrationDaemon(cls, instance): ¶

Kills the migration daemon if present.

@classmethod
def _WriteNICInfoFile(cls, instance, idx, nic): ¶

Write the Xen config file for the instance.

This version of the function just writes the config file from static data.

def _CheckToolstackXlConfigured(self): ¶

Checks whether xl is enabled on an xl-capable node.

Returns
bool	`True` if 'xl' is enabled, `False` otherwise

def _ConfigFileName(self, instance_name): ¶

Get the config file name for an instance.

Parameters
instance_name:str	instance name
Returns
str	fully qualified path to instance config file

def _DestroyInstance(self, name, hvparams): ¶

Destroy an instance if the instance exists.

Parameters
name:string	name of the instance to destroy
hvparams:dict of string	hypervisor parameters of the instance

def _DestroyInstanceIfAlive(self, name, hvparams): ¶

Undocumented

def _GetInstanceList(self, include_node): ¶

Wrapper around module level _GetAllInstanceList.

def _MakeConfigFile(self, instance, startup_memory, block_devices): ¶

Gather configuration details and write to disk.

See _GetConfig for arguments.

def _MigrateInstance(self, instance_name, target, port, hvparams, _ping_fn=netutils.TcpPing): ¶

Migrate an instance to a target node.

See Also
`MigrateInstance` for details

def _ReadConfigFile(self, instance_name): ¶

Returns the contents of the instance config file.

def _RemoveConfigFile(self, instance_name): ¶

Remove the xen configuration file.

def _RenameInstance(self, old_name, new_name): ¶

Rename an instance (domain).

Parameters
old_name:string	current name of the instance
new_name:string	future (requested) name of the instace

def _RunXen(self, args, timeout=None): ¶

Wrapper around utils.process.RunCmd to run Xen command.

Parameters
args	Undocumented
timeout:int or None	if a timeout (in seconds) is specified, the command will be terminated after that number of seconds.
See Also
`utils.process.RunCmd`

def _ShutdownInstance(self, name, hvparams, timeout): ¶

Shutdown an instance if the instance is running.

The '-w' flag waits for shutdown to complete which avoids the need to poll in the case where we want to destroy the domain immediately after shutdown.

Parameters
name:string	name of the instance to stop
hvparams:dict of string	hypervisor parameters of the instance
timeout:int or None	a timeout after which the shutdown command should be killed, or None for no timeout

def _StashConfigFile(self, instance_name): ¶

Move the Xen config file to the log directory and return its new path.

def _StopInstance(self, name, force, hvparams, timeout): ¶

Stop an instance.

Parameters
name:string	name of the instance to destroy
force:boolean	whether to do a "hard" stop (destroy)
hvparams:dict of string	hypervisor parameters of the instance
timeout:int or None	a timeout after which the shutdown command should be killed, or None for no timeout

def _WriteConfigFile(self, instance_name, data): ¶

Write the Xen config file for the instance.

This version of the function just writes the config file from static data.

def _WriteNicConfig(self, config, instance, hvp): ¶

Undocumented

_DIRS = ¶

Undocumented

Value

[_ROOT_DIR, _NICS_DIR, _MIGRATION_DIR]

_INSTANCE_LIST_DELAYS: tuple[float, ...] = ¶

Undocumented

Value

(0.3, 1.5, 1.0)

_INSTANCE_LIST_TIMEOUT: int = ¶

Undocumented

Value

_MIGRATION_DIR = ¶

Undocumented

Value

_ROOT_DIR+'/migration'

_NICS_DIR = ¶

Undocumented

Value

_ROOT_DIR+'/nic'

_ROOT_DIR = ¶

Undocumented

Value

pathutils.RUN_DIR+'/xen-hypervisor'

_cfgdir = ¶

Undocumented

_cmd = ¶

Undocumented

_run_cmd_fn = ¶

Undocumented