mirror of
https://github.com/retspen/webvirtcloud
synced 2026-11-08 11:16:47 +00:00
d3e4ef9132
The move copies the VM's NVRAM file to the destination with libvirt streams (unless both hosts share the NVRAM directory) and removes the copy if the move fails; the source's file goes with the existing cleanup. The undefine keeps the file, as libvirt refuses to undefine a VM with NVRAM otherwise. A VM with TPM state is still refused.
473 lines
21 KiB
Python
473 lines
21 KiB
Python
"""Migration: the source definition never stays behind; a shut-off VM's
|
|
definition is moved by the app, not by libvirt's offline migration."""
|
|
|
|
import contextlib
|
|
import unittest
|
|
from unittest import mock
|
|
|
|
import libvirt
|
|
from django.conf import settings
|
|
|
|
if not settings.configured:
|
|
settings.configure(MAC_OUI="52:54:10")
|
|
|
|
from vrtManager import util
|
|
from vrtManager.instance import wvmInstances
|
|
|
|
|
|
def no_domain():
|
|
error = libvirt.libvirtError("Domain not found")
|
|
error.err = (libvirt.VIR_ERR_NO_DOMAIN,)
|
|
return error
|
|
|
|
|
|
class FakeDomain:
|
|
def __init__(self, xml="<domain/>", snapshots=0, saved=False, undefine_fails=False, undefine_lost=False,
|
|
started=False):
|
|
self.calls = []
|
|
self.xml = xml
|
|
self.snapshots = snapshots
|
|
self.saved = saved
|
|
self.undefine_fails = undefine_fails
|
|
self.undefine_lost = undefine_lost # undefined, but the reply is lost
|
|
self.started = started # started by another client during the move
|
|
self.undefined = None
|
|
self.redefined = []
|
|
self.restored_autostart = None
|
|
|
|
def migrate(self, dconn, flags, dname, uri, bandwidth):
|
|
self.calls.append((flags, uri))
|
|
|
|
def name(self):
|
|
return "vm"
|
|
|
|
def UUIDString(self):
|
|
return "u-1"
|
|
|
|
inactive_xml = None # the persistent definition, when it differs
|
|
|
|
def XMLDesc(self, flags):
|
|
if flags & libvirt.VIR_DOMAIN_XML_INACTIVE and self.inactive_xml:
|
|
return self.inactive_xml
|
|
return self.xml
|
|
|
|
def snapshotNum(self, flags=0):
|
|
return self.snapshots
|
|
|
|
def hasManagedSaveImage(self, flags=0):
|
|
return self.saved
|
|
|
|
def undefineFlags(self, flags):
|
|
if self.undefine_fails:
|
|
raise libvirt.libvirtError("undefine failed")
|
|
self.undefined = flags
|
|
if self.undefine_lost:
|
|
raise libvirt.libvirtError("Cannot recv data")
|
|
|
|
def isPersistent(self):
|
|
return self.undefined is None or bool(self.redefined)
|
|
|
|
def isActive(self):
|
|
if not self.started and self.undefined is not None:
|
|
raise no_domain() # libvirt: an undefined shut-off VM is gone
|
|
return self.started
|
|
|
|
def autostart(self):
|
|
return 1
|
|
|
|
def setAutostart(self, value):
|
|
self.restored_autostart = value
|
|
|
|
def connect(self):
|
|
return self
|
|
|
|
def defineXML(self, xml):
|
|
self.redefined.append(xml)
|
|
return self
|
|
|
|
|
|
def no_volume():
|
|
error = libvirt.libvirtError("Storage volume not found")
|
|
error.err = (libvirt.VIR_ERR_NO_STORAGE_VOL,)
|
|
return error
|
|
|
|
|
|
class FakeVolume:
|
|
def __init__(self, backing):
|
|
self.backing = backing
|
|
|
|
def XMLDesc(self, flags=0):
|
|
if self.backing is None:
|
|
return "<volume><target><path>x</path></target></volume>"
|
|
return f"<volume><backingStore><path>{self.backing}</path></backingStore></volume>"
|
|
|
|
|
|
class FakePool:
|
|
def __init__(self, host, active=True):
|
|
self.host = host
|
|
self.active = active
|
|
|
|
def isActive(self):
|
|
return self.active
|
|
|
|
def refresh(self, flags=0):
|
|
self.host.refreshes += 1
|
|
self.host.volumes |= self.host.unlisted
|
|
self.host.unlisted = set()
|
|
|
|
def storageVolLookupByName(self, name):
|
|
return self.host.storageVolLookupByPath(name)
|
|
|
|
|
|
class FakeHost:
|
|
"""The destination's libvirt connection. volumes: the paths its pools
|
|
list; unlisted: files its pools show after a refresh."""
|
|
|
|
def __init__(self, existing=(), volumes=(), unlisted=(), backing=None, inactive_pools=()):
|
|
self.existing = set(existing)
|
|
self.defined = []
|
|
self.new = []
|
|
self.volumes = set(volumes)
|
|
self.unlisted = set(unlisted)
|
|
self.backing = backing or {} # path: the path of its backing file
|
|
self.inactive_pools = set(inactive_pools)
|
|
self.refreshes = 0
|
|
|
|
def storageVolLookupByPath(self, path):
|
|
if path not in self.volumes:
|
|
raise no_volume()
|
|
return FakeVolume(self.backing.get(path))
|
|
|
|
def storagePoolLookupByName(self, name):
|
|
return FakePool(self, active=name not in self.inactive_pools)
|
|
|
|
def listAllStoragePools(self, flags=0):
|
|
return [FakePool(self)]
|
|
|
|
def lookup(self, key):
|
|
if key in self.existing:
|
|
return FakeDomain()
|
|
raise no_domain()
|
|
|
|
lookupByName = lookupByUUIDString = lookup
|
|
|
|
def defineXML(self, xml):
|
|
self.defined.append(xml)
|
|
self.new.append(FakeDomain())
|
|
return self.new[-1]
|
|
|
|
|
|
class FakeSource:
|
|
def __init__(self, state, nvram=None, **domain):
|
|
self.state = state
|
|
self.nvram = nvram
|
|
self.instance = FakeDomain(**domain)
|
|
|
|
def get_nvram(self):
|
|
return self.nvram
|
|
|
|
reads = 0
|
|
|
|
def get_status(self):
|
|
self.reads += 1
|
|
return self.state
|
|
|
|
def get_arch(self):
|
|
return "x86_64"
|
|
|
|
def get_dom_emulator(self):
|
|
return "/usr/bin/qemu-system-x86_64"
|
|
|
|
|
|
def destination(host=None):
|
|
dest = wvmInstances.__new__(wvmInstances)
|
|
dest.wvm = host or FakeHost()
|
|
dest.get_emulator = lambda arch: "/usr/bin/qemu-system-x86_64"
|
|
return dest
|
|
|
|
|
|
class MigrationFlagsTestCase(unittest.TestCase):
|
|
def test_the_source_definition_is_always_removed(self):
|
|
for state, live, offline in ((1, True, False), (3, False, False)):
|
|
with self.subTest(state=state):
|
|
source = FakeSource(state)
|
|
destination().moveto(source, "vm", live=live, unsafe=False, offline=offline)
|
|
flags = source.instance.calls[0][0]
|
|
self.assertTrue(flags & libvirt.VIR_MIGRATE_UNDEFINE_SOURCE)
|
|
self.assertTrue(flags & libvirt.VIR_MIGRATE_PERSIST_DEST)
|
|
|
|
def test_the_migration_uri_is_passed_on(self):
|
|
source = FakeSource(1)
|
|
destination().moveto(source, "vm", live=True, unsafe=False, offline=False, uri="tcp://192.0.2.12")
|
|
self.assertEqual(source.instance.calls[0][1], "tcp://192.0.2.12")
|
|
source = FakeSource(1)
|
|
destination().moveto(source, "vm", live=True, unsafe=False, offline=False)
|
|
self.assertIsNone(source.instance.calls[0][1])
|
|
|
|
|
|
class ShutOffMigrationTestCase(unittest.TestCase):
|
|
"""libvirt's offline migration fails on some builds (RHEL-156800); a
|
|
shut-off VM is only its definition, so the app moves that itself."""
|
|
|
|
def test_the_definition_moves_to_the_destination(self):
|
|
host = FakeHost()
|
|
source = FakeSource(5, xml="<domain><name>vm</name></domain>")
|
|
destination(host).moveto(source, "vm", live=False, unsafe=False, offline=True)
|
|
self.assertEqual(host.defined, ["<domain><name>vm</name></domain>"])
|
|
self.assertEqual(source.instance.calls, [])
|
|
self.assertEqual(source.instance.undefined, libvirt.VIR_DOMAIN_UNDEFINE_KEEP_NVRAM)
|
|
|
|
def test_a_vm_with_tpm_state_is_refused(self):
|
|
"""That state stays on the source host: the VM would start on the
|
|
destination with a new TPM."""
|
|
host = FakeHost()
|
|
xml = "<domain><devices><tpm model='tpm-crb'><backend type='emulator' version='2.0'/></tpm></devices></domain>"
|
|
source = FakeSource(5, xml=xml)
|
|
with self.assertRaisesRegex(util.OperationError, "migrate it live"):
|
|
destination(host).moveto(source, "vm", live=False, unsafe=False, offline=True)
|
|
self.assertEqual(host.defined, [])
|
|
self.assertIsNone(source.instance.undefined)
|
|
|
|
def test_a_tpm_without_local_state_moves(self):
|
|
xml = "<domain><devices><tpm model='tpm-tis'><backend type='passthrough'/></tpm></devices></domain>"
|
|
host = FakeHost()
|
|
destination(host).moveto(FakeSource(5, xml=xml), "vm", live=False, unsafe=False, offline=True)
|
|
self.assertEqual(host.defined, [xml])
|
|
|
|
def test_refused_before_anything_changes(self):
|
|
cases = {
|
|
"saved state": (FakeHost(), {"saved": True}),
|
|
"same uuid on the destination": (FakeHost(existing={"u-1"}), {}),
|
|
"same name on the destination": (FakeHost(existing={"vm"}), {}),
|
|
}
|
|
for case, (host, domain) in cases.items():
|
|
with self.subTest(case=case):
|
|
source = FakeSource(5, **domain)
|
|
with self.assertRaises(util.OperationError):
|
|
destination(host).moveto(source, "vm", live=False, unsafe=False, offline=True)
|
|
self.assertEqual(host.defined, [])
|
|
self.assertIsNone(source.instance.undefined)
|
|
|
|
def test_a_failed_source_undefine_removes_the_new_definition(self):
|
|
host = FakeHost()
|
|
source = FakeSource(5, undefine_fails=True)
|
|
with self.assertRaises(libvirt.libvirtError):
|
|
destination(host).moveto(source, "vm", live=False, unsafe=False, offline=True)
|
|
self.assertIsNotNone(host.new[0].undefined)
|
|
|
|
def test_the_destination_definition_stays_when_the_source_has_none(self):
|
|
host = FakeHost()
|
|
source = FakeSource(5, undefine_lost=True)
|
|
with self.assertRaisesRegex(util.OperationError, "only on the destination"):
|
|
destination(host).moveto(source, "vm", live=False, unsafe=False, offline=True)
|
|
self.assertIsNone(host.new[0].undefined)
|
|
|
|
def test_a_failed_rollback_is_reported(self):
|
|
host = FakeHost()
|
|
source = FakeSource(5, undefine_fails=True)
|
|
host.defineXML = lambda xml: host.new.append(FakeDomain(undefine_fails=True)) or host.new[-1]
|
|
with self.assertRaisesRegex(util.OperationError, "undefine failed; the VM is now defined on both hosts"):
|
|
destination(host).moveto(source, "vm", live=False, unsafe=False, offline=True)
|
|
|
|
def test_a_vm_started_meanwhile_stays_on_the_source(self):
|
|
host = FakeHost()
|
|
source = FakeSource(5, xml="<domain><name>vm</name></domain>", started=True)
|
|
with self.assertRaisesRegex(util.OperationError, "started on the source"):
|
|
destination(host).moveto(source, "vm", live=False, unsafe=False, offline=True)
|
|
self.assertEqual(source.instance.redefined, ["<domain><name>vm</name></domain>"])
|
|
self.assertEqual(source.instance.restored_autostart, 1)
|
|
self.assertIsNotNone(host.new[0].undefined)
|
|
|
|
|
|
class MigrationModeTestCase(unittest.TestCase):
|
|
"""The state is read once; a request that does not fit it is refused
|
|
before anything changes, and moveto names the mode it used."""
|
|
|
|
def migrate(self, state, **request):
|
|
source = FakeSource(state)
|
|
options = {"live": False, "unsafe": False, "offline": False, **request}
|
|
mode = destination().moveto(source, "vm", **options)
|
|
return mode, source.instance.calls[0][0] if source.instance.calls else None
|
|
|
|
def test_refused_requests(self):
|
|
for state, request in ((5, {"live": True}), (1, {"offline": True}), (3, {"offline": True}),
|
|
(1, {"live": True, "offline": True}), (6, {}), (4, {}), (7, {}), (0, {})):
|
|
with self.subTest(state=state, request=request):
|
|
source = FakeSource(state)
|
|
with self.assertRaises(util.OperationError):
|
|
destination().moveto(source, "vm", unsafe=False, **{"live": False, "offline": False, **request})
|
|
self.assertEqual(source.instance.calls, [])
|
|
|
|
def test_a_vm_with_snapshots_is_refused_in_every_state(self):
|
|
"""libvirt keeps snapshot metadata on the source host; a migration
|
|
does not carry it, even with shared disks."""
|
|
for state, request in ((1, {"live": True}), (1, {}), (3, {}), (5, {})):
|
|
with self.subTest(state=state, request=request):
|
|
host = FakeHost()
|
|
source = FakeSource(state, snapshots=1)
|
|
with self.assertRaisesRegex(util.OperationError, "A VM with snapshots cannot be migrated"):
|
|
destination(host).moveto(source, "vm", unsafe=False, **{"live": False, "offline": False, **request})
|
|
self.assertEqual(source.instance.calls, [])
|
|
self.assertEqual(host.defined, [])
|
|
|
|
def test_modes(self):
|
|
live, unsafe = libvirt.VIR_MIGRATE_LIVE, libvirt.VIR_MIGRATE_UNSAFE
|
|
converge, compressed = libvirt.VIR_MIGRATE_AUTO_CONVERGE, libvirt.VIR_MIGRATE_COMPRESSED
|
|
mode, flags = self.migrate(1, live=True, autoconverge=True, compress=True, unsafe=True)
|
|
self.assertEqual(mode, "live, unsafe, auto converge, compressed")
|
|
self.assertEqual(flags & (live | unsafe | converge | compressed), live | unsafe | converge | compressed)
|
|
source = FakeSource(1)
|
|
destination().moveto(source, "vm", live=True, unsafe=False, offline=False)
|
|
self.assertEqual(source.reads, 1)
|
|
mode, flags = self.migrate(1, compress=True, autoconverge=True)
|
|
self.assertEqual(mode, "non-live, compressed")
|
|
self.assertEqual(flags & (live | converge | compressed), compressed)
|
|
# a paused VM stays paused; the tuning options are for running VMs
|
|
mode, flags = self.migrate(3, live=True, autoconverge=True, compress=True, unsafe=True)
|
|
self.assertEqual(mode, "live")
|
|
self.assertEqual(flags & (live | unsafe | converge | compressed), live)
|
|
self.assertEqual(self.migrate(5), ("offline", None))
|
|
self.assertEqual(self.migrate(5, offline=True), ("offline", None))
|
|
|
|
|
|
def with_disks(*disks):
|
|
return "<domain><devices>%s</devices></domain>" % "".join(disks)
|
|
|
|
|
|
FILE_DISK = "<disk type='file' device='disk'><source file='/pool/vm.qcow2'/><target dev='vda'/></disk>"
|
|
|
|
|
|
class DestinationDisksTestCase(unittest.TestCase):
|
|
"""Every disk of the VM must be a volume the destination knows; the
|
|
VM is refused before anything changes otherwise, naming the disks."""
|
|
|
|
def migrate(self, host, xml, state=1, inactive_xml=None):
|
|
source = FakeSource(state, xml=xml)
|
|
source.instance.inactive_xml = inactive_xml
|
|
live = state != 5
|
|
destination(host).moveto(source, "vm", live=live, unsafe=False, offline=not live)
|
|
return source
|
|
|
|
def test_known_volumes_migrate(self):
|
|
host = FakeHost(volumes={"/pool/vm.qcow2", "/pool/base.qcow2", "/iso/os.iso"})
|
|
xml = with_disks(
|
|
"<disk type='file' device='disk'><source file='/pool/vm.qcow2'/><target dev='vda'/>"
|
|
"<backingStore type='file'><source file='/pool/base.qcow2'/><backingStore/></backingStore></disk>",
|
|
"<disk type='file' device='cdrom'><source file='/iso/os.iso'/><target dev='sda'/></disk>",
|
|
"<disk type='file' device='cdrom'><target dev='sdb'/></disk>", # empty
|
|
"<disk type='network' device='disk'><source protocol='rbd' name='rbd/vm'/><target dev='vdb'/></disk>",
|
|
"<disk type='volume' device='disk'><source pool='p' volume='/pool/vm.qcow2'/><target dev='vdc'/></disk>",
|
|
)
|
|
self.assertEqual(len(self.migrate(host, xml).instance.calls), 1)
|
|
self.assertEqual(host.defined, [])
|
|
self.migrate(host, xml, state=5)
|
|
self.assertEqual(len(host.defined), 1)
|
|
|
|
def test_missing_disks_are_refused_and_named(self):
|
|
cases = {
|
|
"vda \\(/pool/vm.qcow2\\)": with_disks(FILE_DISK),
|
|
"sda \\(/iso/os.iso\\)": with_disks(
|
|
"<disk type='file' device='cdrom'><source file='/iso/os.iso'/><target dev='sda'/></disk>"),
|
|
"vda \\(/pool/base.qcow2\\)": with_disks(
|
|
"<disk type='file' device='disk'><source file='/pool/vm.qcow2'/><target dev='vda'/>"
|
|
"<backingStore type='file'><source file='/pool/base.qcow2'/></backingStore></disk>"),
|
|
"vdb \\(/dev/sdz\\)": with_disks(
|
|
"<disk type='block' device='disk'><source dev='/dev/sdz'/><target dev='vdb'/></disk>"),
|
|
"vdc \\(p/v\\)": with_disks(
|
|
"<disk type='volume' device='disk'><source pool='p' volume='v'/><target dev='vdc'/></disk>"),
|
|
}
|
|
for missing, xml in cases.items():
|
|
for state in (1, 5):
|
|
with self.subTest(missing=missing, state=state):
|
|
host = FakeHost(volumes=set() if "vm.qcow2" in missing else {"/pool/vm.qcow2"})
|
|
source = FakeSource(state, xml=xml)
|
|
with self.assertRaisesRegex(util.OperationError, missing):
|
|
destination(host).moveto(source, "vm", live=state == 1, unsafe=False, offline=state == 5)
|
|
self.assertEqual((source.instance.calls, host.defined), ([], []))
|
|
|
|
def test_a_disk_of_the_persistent_definition_is_checked_too(self):
|
|
host = FakeHost(volumes={"/pool/vm.qcow2"})
|
|
inactive = with_disks(FILE_DISK, "<disk type='file' device='disk'><source file='/pool/data.img'/>"
|
|
"<target dev='vdb'/></disk>")
|
|
with self.assertRaisesRegex(util.OperationError, "vdb \\(/pool/data.img\\)"):
|
|
self.migrate(host, with_disks(FILE_DISK), inactive_xml=inactive)
|
|
|
|
def test_pools_are_refreshed_before_a_disk_counts_as_missing(self):
|
|
# a file another host made on shared storage is listed after a refresh
|
|
host = FakeHost(unlisted={"/pool/vm.qcow2"})
|
|
self.assertEqual(len(self.migrate(host, with_disks(FILE_DISK)).instance.calls), 1)
|
|
self.assertEqual(host.refreshes, 1)
|
|
host = FakeHost(volumes={"/pool/vm.qcow2"})
|
|
self.migrate(host, with_disks(FILE_DISK))
|
|
self.assertEqual(host.refreshes, 0)
|
|
|
|
def test_backing_files_the_definition_does_not_list_are_checked(self):
|
|
# an inactive definition has no <backingStore>: the volume tells
|
|
for state in (1, 5):
|
|
with self.subTest(state=state):
|
|
host = FakeHost(volumes={"/pool/vm.qcow2", "/pool/mid.qcow2"},
|
|
backing={"/pool/vm.qcow2": "/pool/mid.qcow2", "/pool/mid.qcow2": "/local/base.qcow2"})
|
|
with self.assertRaisesRegex(util.OperationError, "vda \\(/local/base.qcow2\\)"):
|
|
self.migrate(host, with_disks(FILE_DISK), state=state)
|
|
host.volumes.add("/local/base.qcow2")
|
|
self.migrate(host, with_disks(FILE_DISK), state=state)
|
|
|
|
def test_a_network_backing_image_is_not_checked(self):
|
|
host = FakeHost(volumes={"/pool/vm.qcow2"}, backing={"/pool/vm.qcow2": "nbd://storage.example.org:10809/base"})
|
|
self.assertEqual(len(self.migrate(host, with_disks(FILE_DISK)).instance.calls), 1)
|
|
|
|
def test_disks_that_cannot_be_checked_are_refused(self):
|
|
xml = with_disks("<disk type='dir' device='disk'><source dir='/srv/vm'/><target dev='vdb'/></disk>")
|
|
with self.assertRaisesRegex(util.OperationError, "vdb \\(dir disk, cannot be checked\\)"):
|
|
self.migrate(FakeHost(), xml, state=5)
|
|
|
|
def test_a_volume_of_an_inactive_pool_is_missing(self):
|
|
host = FakeHost(volumes={"v"}, inactive_pools={"p"})
|
|
xml = with_disks("<disk type='volume' device='disk'><source pool='p' volume='v'/><target dev='vdc'/></disk>")
|
|
with self.assertRaisesRegex(util.OperationError, "vdc \\(p/v\\)"):
|
|
self.migrate(host, xml)
|
|
|
|
|
|
class NvramCopyTestCase(unittest.TestCase):
|
|
"""A shut-off move copies the UEFI variables file to the destination."""
|
|
|
|
PATH = "/var/lib/libvirt/qemu/nvram/vm_VARS.fd"
|
|
|
|
def setUp(self):
|
|
self.source = FakeSource(5, nvram=self.PATH, xml="<domain><name>vm</name></domain>")
|
|
self.source.wvm = mock.MagicMock()
|
|
self.source.wvm.newStream.return_value.recvAll.side_effect = lambda fn, out: fn(None, b"vars", out)
|
|
self.source_pool = mock.MagicMock()
|
|
self.source._nvram_pool = lambda: contextlib.nullcontext(self.source_pool)
|
|
self.host = FakeHost()
|
|
self.dest = destination(self.host)
|
|
self.dest_pool = mock.MagicMock()
|
|
self.dest._nvram_pool = lambda: contextlib.nullcontext(self.dest_pool)
|
|
self.dest.wvm.newStream = mock.MagicMock()
|
|
self.shared = mock.patch.object(wvmInstances, "_nvram_shared", return_value=False)
|
|
self.shared.start()
|
|
self.addCleanup(self.shared.stop)
|
|
|
|
def move(self):
|
|
self.dest.moveto(self.source, "vm", live=False, unsafe=False, offline=True)
|
|
|
|
def test_the_file_is_copied_before_the_definition(self):
|
|
self.move()
|
|
copy = self.dest_pool.createXML.return_value
|
|
self.assertIn("<name>vm_VARS.fd</name><capacity>4</capacity>", self.dest_pool.createXML.call_args[0][0])
|
|
copy.upload.assert_called_once_with(self.dest.wvm.newStream.return_value, 0, 4, 0)
|
|
self.assertEqual(self.host.defined, ["<domain><name>vm</name></domain>"])
|
|
|
|
def test_a_shared_directory_is_not_copied(self):
|
|
self.shared.stop()
|
|
with mock.patch.object(wvmInstances, "_nvram_shared", return_value=True):
|
|
self.move()
|
|
self.dest_pool.createXML.assert_not_called()
|
|
self.shared.start()
|
|
|
|
def test_the_copy_is_deleted_when_the_definition_fails(self):
|
|
self.host.defineXML = mock.MagicMock(side_effect=libvirt.libvirtError("define failed"))
|
|
with self.assertRaisesRegex(libvirt.libvirtError, "define failed"):
|
|
self.move()
|
|
self.dest_pool.storageVolLookupByName.assert_called_once_with("vm_VARS.fd")
|
|
self.dest_pool.storageVolLookupByName.return_value.delete.assert_called_once_with(0)
|