lago.providers.libvirt package

Submodules

lago.providers.libvirt.cpu module

class lago.providers.libvirt.cpu.CPU(spec, host_cpu)

Bases: object

cpu_xml

generate_cpu_xml()

Get CPU XML

Returns:cpu node Return type:lxml.etree.Element

generate_custom(cpu, vcpu_num, fill_topology)

Generate custom CPU model. This method attempts to convert the dict to XML, as defined by xmltodict.unparse method.

Parameters:

• cpu (dict) – CPU spec
• vcpu_num (int) – number of virtual cpus
• fill_topology (bool) – if topology is not defined in cpu and vcpu was not set, will add CPU topology to the generated CPU.

Returns:

CPU XML node

Return type:

lxml.etree.Element

Raises:

LagoInitException – when failed to convert dict to XML

generate_exact(model, vcpu_num, host_cpu)

Generate exact CPU model with nested virtualization CPU feature.

Parameters:

• model (str) – libvirt supported CPU model
• vcpu_num (int) – number of virtual cpus
• host_cpu (lxml.etree.Element) – the host CPU model

Returns:

CPU XML node

Return type:

lxml.etree.Element

generate_feature(name, policy='require')

Generate CPU feature element

Parameters:

• name (str) – feature name
• policy (str) – libvirt feature policy

Returns:

feature XML element

Return type:

lxml.etree.Element

generate_host_passthrough(vcpu_num)

Generate host-passthrough XML cpu node

Parameters:vcpu_num (str) – number of virtual CPUs Returns:CPU XML node Return type:lxml.etree.Element

generate_numa(vcpu_num)

Generate guest CPU <numa> XML child Configures 1, 2 or 4 vCPUs per cell.

Parameters:vcpu_num (str) – number of virtual CPUs Returns:numa XML element Return type:lxml.etree.Element

generate_topology(vcpu_num, cores=1, threads=1)

Generate CPU <topology> XML child

Parameters:

• vcpu_num (str) – number of virtual CPUs
• cores (int) – number of cores
• threads (int) – number of threads

Returns:

topology XML element

Return type:

lxml.etree.Element

generate_vcpu(vcpu_num)

Generate <vcpu> domain XML child

Parameters:vcpu_num (str) – number of virtual cpus Returns:vcpu XML element Return type:lxml.etree.Element

generate_vcpu_xml(vcpu_num)

Parameters:vcpu_num (int) – number of virtual cpus Returns:vcpu XML node Return type:lxml.etree.Element

model

validate()

Validate CPU-related VM spec are compatible

Raises:LagoInitException – if both ‘cpu_model’ and ‘cpu_custom’ are defined.

vcpu_xml

vendor

class lago.providers.libvirt.cpu.LibvirtCPU

Bases: object

Query data from /usr/share/libvirt/cpu_map.xml

classmethod get_cpu_props(family, arch='x86')

Get CPU info XML

Parameters:

• family (str) – CPU family
• arch (str) – CPU arch

Returns:

CPU xml

Return type:

lxml.etree.Element

Raises:

LagoException – If no such CPU family exists

classmethod get_cpu_vendor(family, arch='x86')

Get CPU vendor, if vendor is not available will return ‘generic’

Parameters:

• family (str) – CPU family
• arch (str) – CPU arch

Returns:

CPU vendor if found otherwise ‘generic’

Return type:

str

classmethod get_cpus_by_arch(arch)

Get all CPUs info by arch

Parameters:arch (str) – CPU architecture Returns:CPUs by arch XML Return type:lxml.etree.element Raises:LagoException – If no such ARCH is found

lago.providers.libvirt.cpu.create_xml_map(cpu_map_index_xml, cpu_map_dir)

lago.providers.libvirt.network module

class lago.providers.libvirt.network.BridgeNetwork(env, spec, compat)

Bases: lago.providers.libvirt.network.Network

_libvirt_xml()

start()

Start the network, will check if the network is active attempts times, waiting timeout between each attempt.

Parameters:

• attempts (int) – number of attempts to check the network is active
• timeout (int) – timeout for each attempt

Returns:

None

Raises:

• RuntimeError – if network creation failed, or failed to verify it is
• active.

stop()

class lago.providers.libvirt.network.NATNetwork(env, spec, compat)

Bases: lago.providers.libvirt.network.Network

_generate_dns_disable()

_generate_dns_forward(forward_ip)

_generate_main_dns(records, subnet, forward_plain='no')

_ipv6_prefix(subnet, const='fd8f:1391:3a82:')

_libvirt_xml()

class lago.providers.libvirt.network.Network(env, spec, compat)

Bases: object

_libvirt_name()

_libvirt_xml()

add_mapping(name, ip, save=True)

add_mappings(mappings)

alive()

gw()

is_management()

mapping()

mtu()

name()

resolve(name)

save()

spec

start(attempts=5, timeout=2)

Start the network, will check if the network is active attempts times, waiting timeout between each attempt.

Parameters:

• attempts (int) – number of attempts to check the network is active
• timeout (int) – timeout for each attempt

Returns:

None

Raises:

• RuntimeError – if network creation failed, or failed to verify it is
• active.

stop()

lago.providers.libvirt.utils module

lago.providers.libvirt.utils.DOMAIN_STATES = {<sphinx.ext.autodoc.importer._MockObject object>: 'no state', <sphinx.ext.autodoc.importer._MockObject object>: 'running', <sphinx.ext.autodoc.importer._MockObject object>: 'blocked', <sphinx.ext.autodoc.importer._MockObject object>: 'paused', <sphinx.ext.autodoc.importer._MockObject object>: 'begin shut down', <sphinx.ext.autodoc.importer._MockObject object>: 'shut off', <sphinx.ext.autodoc.importer._MockObject object>: 'crashed', <sphinx.ext.autodoc.importer._MockObject object>: 'suspended'}

Mapping of domain statuses values to human readable strings

class lago.providers.libvirt.utils.Domain

Bases: object

Class to namespace libvirt domain related helpers

static resolve_state(state_number)

Get a nice description from a domain state number

Parameters:state_number (list of int) – State number as returned by libvirt.virDomain.state() Returns:

small human readable description of the domain state, unknown

if the state is not in the known list

Return type:str

lago.providers.libvirt.utils.LIBVIRT_CONNECTIONS = {}

Singleton with the cached opened libvirt connections

lago.providers.libvirt.utils.auth_callback(credentials, user_data)

lago.providers.libvirt.utils.dict_to_xml(spec, full_document=False)

Convert dict to XML

Parameters:

• spec (dict) – dict to convert
• full_document (bool) – whether to add XML headers

Returns:

XML tree

Return type:

lxml.etree.Element

lago.providers.libvirt.utils.get_domain_template(distro, libvirt_ver, **kwargs)

Get a rendered Jinja2 domain template

Parameters:

• distro (str) – domain distro
• libvirt_ver (int) – libvirt version
• kwargs (dict) – args for template render

Returns:

rendered template

Return type:

str

lago.providers.libvirt.utils.get_libvirt_connection(name)

lago.providers.libvirt.utils.get_template(basename)

Load a file as a string from the templates directory

Parameters:basename (str) – filename Returns:string representation of the file Return type:str

lago.providers.libvirt.utils.libvirt_callback(userdata, err)

lago.providers.libvirt.vm module

exception lago.providers.libvirt.vm.LagoLocalLibvirtVMProviderException

Bases: lago.utils.LagoException

class lago.providers.libvirt.vm.LocalLibvirtVMProvider(vm)

Bases: lago.plugins.vm.VMProviderPlugin

_createXML(dom_xml, flags=0)

_create_dead_snapshot(name)

_create_live_snapshot(name)

_get_domain()

Return the object representation of this provider VM.

Returns:Libvirt domain object Return type:libvirt.virDomain Raises:exc:`~lago.plugins.vm.LagoFailedToGetVMStateError: If the VM exist, but the query returned an error.

_get_qemu_kvm_path()

_libvirt_name()

_libvirt_xml()

_load_xml()

_reclaim_disk(path)

_reclaim_disks()

_shutdown(libvirt_cmd, ssh_cmd, msg)

Choose the invoking method (using libvirt or ssh) to shutdown / poweroff the domain.

If acpi is defined in the domain use libvirt, otherwise use ssh.

Parameters:

• libvirt_cmd (function) – Libvirt function the invoke
• ssh_cmd (list of str) – Shell command to invoke on the domain
• msg (str) – Name of the command that should be inserted to the log message.

Returns

None

Raises:RuntimeError – If acpi is not configured an ssh isn’t available

alive()

bootstrap()

Does any actions needed to get the domain ready to be used, ran on prefix init. :returns: None

caps

cpu

cpu_model

VM CPU model

Returns:CPU model Return type:str

cpu_vendor

VM CPU Vendor

Returns:CPU vendor Return type:str

create_snapshot(name)

Take any actions needed to create a snapshot :param name: Name for the snapshot, will be used as key to retrieve

it later

Returns:None

export_disks(standalone, dst_dir, compress, collect_only=False, with_threads=True, *args, **kwargs)

Export all the disks of self.

Parameters:

• standalone (bool) – if true, merge the base images and the layered image into a new file (Supported only in qcow2 format)
• dst_dir (str) – dir to place the exported disks
• compress (bool) – if true, compress each disk.
• collect_only (bool) – If true, return only a dict which maps between the name of the vm to the paths of the disks that will be exported (don’t export anything).
• with_threads (bool) – If True, export disks in parallel

Returns:

which maps between the name of the vm to the paths of the disks that will be exported

Return type:

(dict)

extract_paths(paths, ignore_nopath)

Extract the given paths from the domain

Attempt to extract all files defined in paths with the method defined in extract_paths(), if it fails, and guestfs is available it will try extracting the files with guestfs.

Parameters:

• paths (list of tuples) – files to extract in [(src1, dst1), (src2, dst2)…] format.
• ignore_nopath (boolean) – if True will ignore none existing paths.

Returns:

None

Raises:

• ExtractPathNoPathError – if a none existing path was found on the VM, and ignore_nopath is False.
• ExtractPathError – on all other failures.

extract_paths_dead(paths, ignore_nopath)

Extract the given paths from the domain using guestfs. Using guestfs can have side-effects and should be used as a second option, mainly when SSH is not available.

Parameters:

• paths (list of str) – paths to extract
• ignore_nopath (boolean) – if True will ignore none existing paths.

Returns:

None

Raises:

• LagoException – if guestfs is not importable.
• ExtractPathNoPathError – if a none existing path was found on the VM, and ignore_nopath is True.
• ExtractPathError – on failure extracting the files.

interactive_console()

Opens an interactive console

Returns:result of the virsh command execution Return type:lago.utils.CommandStatus

libvirt_ver

raw_state()

Return the state of the domain in Libvirt’s terms

Retruns:

tuple of ints: The state and its reason

Raises:

• LagoVMDoesNotExistError – If the VM of this provider doesn’t exist.
• exc:`~lago.plugins.vm.LagoFailedToGetVMStateError: If the VM exist, but the query returned an error.

reboot(*args, **kwargs)

Reboot a domain :returns: None

revert_snapshot(name)

Take any actions needed to revert/restore a snapshot :param name: Name for the snapshot, same that was set on creation :type name: str

Returns:None

running()

Returns: (bool): True if the VM is running

shutdown(*args, **kwargs)

Shutdown a domain :returns: None

start()

Start a domain :returns: None

state()

Return a small description of the current status of the domain

Returns:small description of the domain status, ‘down’ if it’s not found at all. Return type:str

stop()

Stop a domain :returns: None

lago.providers.libvirt.vm.log_task(task, level='info', propagate_fail=True, uuid=None)

Parameterized decorator to wrap a function in a log task

Example

>>> @log_task('mytask')
... def do_something():
...     pass