ganeti.hypervisor.hv

module documentation

Xen hypervisors

Class	`XenHvmHypervisor`	Xen HVM hypervisor interface
Class	`XenHypervisor`	Xen generic hypervisor interface
Class	`XenPvmHypervisor`	Xen PVM hypervisor interface
Function	`WriteXenConfigEvents`	Undocumented
Constant	`VIF_BRIDGE_SCRIPT`	Undocumented
Constant	`XEN_COMMAND`	Undocumented
Constant	`XL_CONFIG_FILE`	Undocumented
Exception	`_InstanceCrashed`	Instance has reached a violent ending.
Function	`_ConfigureNIC`	Run the network configuration script for a specified NIC
Function	`_CreateConfigCpus`	Create a CPU config string for Xen's config file.
Function	`_GetAllInstanceList`	Return the list of instances including running and shutdown.
Function	`_GetConfigFileDiskData`	Get disk directives for Xen config file.
Function	`_GetNodeInfo`	Combines `_MergeInstanceInfo` and `_ParseNodeInfo`.
Function	`_GetRunningInstanceList`	Return the list of running instances.
Function	`_GetShutdownInstanceList`	Return the list of shutdown instances.
Function	`_IgnorePaused`	Removes information about whether a Xen state is paused from the state.
Function	`_InstanceDomID`	Get instance domain ID from instance info tuple.
Function	`_InstanceRunning`	Get instance runtime from instance info tuple.
Function	`_InstanceRuntime`	Get instance runtime from instance info tuple.
Function	`_IsCrashed`	Returns whether an instance is in the crashed Xen state.
Function	`_IsInstanceRunning`	Determine whether an instance is running.
Function	`_IsInstanceShutdown`	Determine whether the instance is shutdown.
Function	`_MergeInstanceInfo`	Updates node information from `_ParseNodeInfo` with instance info.
Function	`_ParseInstanceList`	Parses the output of listing instances by xen.
Function	`_ParseNodeInfo`	Return information about the node.
Function	`_QuoteCpuidField`	Add quotes around the CPUID field only if necessary.
Function	`_RunInstanceList`	Helper function for `_GetAllInstanceList` to retrieve the list of instances from xen.
Function	`_XenToHypervisorInstanceState`	Maps Xen states to hypervisor states.
Constant	`_DOM0_NAME`	Undocumented
Constant	`_FILE_DRIVER_MAP`	Undocumented

def WriteXenConfigEvents(config, hvp): ¶

Undocumented

VIF_BRIDGE_SCRIPT = ¶

Undocumented

Value

utils.PathJoin(pathutils.XEN_CONFIG_DIR, 'scripts/vif-bridge')

XEN_COMMAND: str = ¶

Undocumented

Value

'xl'

XL_CONFIG_FILE = ¶

Undocumented

Value

utils.PathJoin(pathutils.XEN_CONFIG_DIR, 'xen/xl.conf')

def _ConfigureNIC(instance, seq, nic, tap): ¶

Run the network configuration script for a specified NIC

See hv_base.ConfigureNIC.

Parameters
instance:instance object	instance we're acting on
seq:int	nic sequence number
nic:nic object	nic we're acting on
tap:str	the host's tap interface this NIC corresponds to

def _CreateConfigCpus(cpu_mask): ¶

Create a CPU config string for Xen's config file.

def _GetAllInstanceList(fn, include_node, delays, timeout): ¶

Return the list of instances including running and shutdown.

See _RunInstanceList and _ParseInstanceList for parameter details.

def _GetConfigFileDiskData(block_devices, blockdev_prefix, _letters=_DISK_LETTERS): ¶

Get disk directives for Xen config file.

This method builds the xen config disk directive according to the given disk_template and block_devices.

Parameters
block_devices	list of tuples (cfdev, rldev): cfdev: dict containing ganeti config disk part rldev: ganeti.block.bdev.BlockDev object
blockdev_prefix	a string containing blockdevice prefix, e.g. "sd" for /dev/sda
_letters	Undocumented
Returns
string containing disk directive for xen instance config file

def _GetNodeInfo(info, instance_list): ¶

Combines _MergeInstanceInfo and _ParseNodeInfo.

Parameters
info	Undocumented
instance_list:list of tuples	list of instance information; one tuple per instance

def _GetRunningInstanceList(fn, include_node, delays, timeout): ¶

Return the list of running instances.

See _GetAllInstanceList for parameter details.

def _GetShutdownInstanceList(fn, include_node, delays, timeout): ¶

Return the list of shutdown instances.

See _GetAllInstanceList for parameter details.

def _IgnorePaused(instance_info): ¶

Removes information about whether a Xen state is paused from the state.

As it turns out, an instance can be reported as paused in almost any condition. Paused instances can be paused, running instances can be paused for scheduling, and any other condition can appear to be paused as a result of races or improbable conditions in Xen's status reporting. As we do not use Xen's pause commands in any way at the time, we can simply ignore the paused field and save ourselves a lot of trouble.

Should we ever use the pause commands, several samples would be needed before we could confirm the domain as paused.

def _InstanceDomID(info): ¶

Get instance domain ID from instance info tuple.

Parameters
info:tuple	instance info as parsed by _ParseInstanceList()
Returns
int, instance domain ID

def _InstanceRunning(info): ¶

Get instance runtime from instance info tuple.

Parameters
info:tuple	instance info as parsed by _ParseInstanceList()
Returns
bool

def _InstanceRuntime(info): ¶

Get instance runtime from instance info tuple.

Parameters
info:tuple	instance info as parsed by _ParseInstanceList()
Returns
float value of instance runtime

def _IsCrashed(instance_info): ¶

Returns whether an instance is in the crashed Xen state.

When a horrible misconfiguration happens to a Xen domain, it can crash, meaning that it encounters a violent ending. While this state usually flashes only temporarily before the domain is restarted, being able to check for it allows Ganeti not to act confused and do something about it.

def _IsInstanceRunning(instance_info): ¶

Determine whether an instance is running.

An instance is running if it is in the following Xen states: running, blocked, paused, or dying (about to be destroyed / shutdown).

For some strange reason, Xen once printed 'rb----' which does not make any sense because an instance cannot be both running and blocked. Fortunately, for Ganeti 'running' or 'blocked' is the same as 'running'.

A state of nothing '------' means that the domain is runnable but it is not currently running. That means it is in the queue behind other domains waiting to be scheduled to run. http://old-list-archives.xenproject.org/xen-users/2007-06/msg00849.html

A dying instance is about to be removed, but it is still consuming resources, and counts as running.

Parameters
instance_info:string	Information about instance, as supplied by Xen.
Returns
bool	Whether an instance is running.

def _IsInstanceShutdown(instance_info): ¶

Determine whether the instance is shutdown.

An instance is shutdown when a user shuts it down from within, and we do not remove domains to be able to detect that.

The dying state has been added as a precaution, as Xen's status reporting is weird.

def _MergeInstanceInfo(info, instance_list): ¶

Updates node information from _ParseNodeInfo with instance info.

Parameters
info:dict	Result from `_ParseNodeInfo`
instance_list:list of tuples	list of instance information; one tuple per instance
Returns
dict	Undocumented

def _ParseInstanceList(lines, include_node): ¶

Parses the output of listing instances by xen.

Parameters
lines:list	Result of retrieving the instance list from xen
include_node:boolean	If True, return information for Dom0
Returns
list of tuple containing (name, id, memory, vcpus, state, time spent)

def _ParseNodeInfo(info): ¶

Return information about the node.

Returns

a dict with the following keys (memory values in MiB):

memory_total: the total memory size on the node
memory_free: the available memory on the node for instances
nr_cpus: total number of CPUs
nr_nodes: in a NUMA system, the number of domains
nr_sockets: the number of physical CPU sockets in the node
hv_version: the hypervisor version in the form (major, minor)

def _QuoteCpuidField(data): ¶

Add quotes around the CPUID field only if necessary.

Xen CPUID fields come in two shapes: LIBXL strings, which need quotes around them, and lists of XEND strings, which don't.

Parameters
data	Either type of parameter.
Returns
The quoted version thereof.

def _RunInstanceList(fn, instance_list_errors): ¶

Helper function for _GetAllInstanceList to retrieve the list of instances from xen.

Parameters
fn:callable	Function to query xen for the list of instances
instance_list_errors:list	Error list
Returns
list	Undocumented

def _XenToHypervisorInstanceState(instance_info): ¶

Maps Xen states to hypervisor states.

Parameters
instance_info:string	Information about instance, as supplied by Xen.
Returns
`hv_base.HvInstanceState`	Undocumented

_DOM0_NAME: str = ¶

Undocumented

Value

'Domain-0'

_FILE_DRIVER_MAP = ¶

Undocumented

Value

{constants.FD_LOOP: 'file',
 constants.FD_BLKTAP: 'tap:aio',
 constants.FD_BLKTAP2: 'tap2:tapdisk:aio'}

ganeti.hypervisor.hv_xen

`ganeti.hypervisor.hv_xen`