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# Copyright (C) 2007, 2011, 2012, 2013 Google Inc.

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"""Instance related QA tests.

"""

import operator

import re

from ganeti import utils

from ganeti import constants

from ganeti import query

from ganeti import pathutils

import qa_config

import qa_utils

import qa_error

from qa_utils import AssertIn, AssertCommand, AssertEqual

from qa_utils import InstanceCheck, INST_DOWN, INST_UP, FIRST_ARG, RETURN_VALUE

def _GetDiskStatePath(disk):

  return "/sys/block/%s/device/state" % disk

def _GetGenericAddParameters(inst, disk_template, force_mac=None):

  params = ["-B"]

  params.append("%s=%s,%s=%s" % (constants.BE_MINMEM,

                                 qa_config.get(constants.BE_MINMEM),

                                 constants.BE_MAXMEM,

                                 qa_config.get(constants.BE_MAXMEM)))

  if disk_template != constants.DT_DISKLESS:

    for idx, size in enumerate(qa_config.get("disk")):

      params.extend(["--disk", "%s:size=%s" % (idx, size)])

  # Set static MAC address if configured

  if force_mac:

    nic0_mac = force_mac

  else:

    nic0_mac = inst.GetNicMacAddr(0, None)

  if nic0_mac:

    params.extend(["--net", "0:mac=%s" % nic0_mac])

  return params

def _DiskTest(node, disk_template, fail=False):

  instance = qa_config.AcquireInstance()

  try:

    cmd = (["gnt-instance", "add",

            "--os-type=%s" % qa_config.get("os"),

            "--disk-template=%s" % disk_template,

            "--node=%s" % node] +

           _GetGenericAddParameters(instance, disk_template))

    cmd.append(instance.name)

    AssertCommand(cmd, fail=fail)

    if not fail:

      _CheckSsconfInstanceList(instance.name)

      instance.SetDiskTemplate(disk_template)

      return instance

  except:

    instance.Release()

    raise

  # Handle the case where creation is expected to fail

  assert fail

  instance.Release()

  return None

def _GetInstanceInfo(instance):

  """Return information about the actual state of an instance.

  @type instance: string

  @param instance: the instance name

  @return: a dictionary with the following keys:

      - "nodes": instance nodes, a list of strings

      - "volumes": instance volume IDs, a list of strings

      - "drbd-minors": DRBD minors used by the instance, a dictionary where

        keys are nodes, and values are lists of integers (or an empty

        dictionary for non-DRBD instances)

  """

  master = qa_config.GetMasterNode()

  infocmd = utils.ShellQuoteArgs(["gnt-instance", "info", instance])

  info_out = qa_utils.GetCommandOutput(master.primary, infocmd)

  re_node = re.compile(r"^\s+-\s+(?:primary|secondaries):\s+(\S.+)$")

  node_elem = r"([^,()]+)(?:\s+\([^)]+\))?"

  # re_nodelist matches a list of nodes returned by gnt-instance info, e.g.:

  #  node1.fqdn

  #  node2.fqdn,node3.fqdn

  #  node4.fqdn (group mygroup, group UUID 01234567-abcd-0123-4567-0123456789ab)

  # FIXME This works with no more than 2 secondaries

  re_nodelist = re.compile(node_elem + "(?:," + node_elem + ")?$")

  re_vol = re.compile(r"^\s+logical_id:\s+(\S+)$")

  re_drbdnode = re.compile(r"^\s+node[AB]:\s+([^\s,]+),\s+minor=([0-9]+)$")

  nodes = []

  vols = []

  drbd_min = {}

  for line in info_out.splitlines():

    m = re_node.match(line)

    if m:

      nodestr = m.group(1)

      m2 = re_nodelist.match(nodestr)

      if m2:

        nodes.extend(filter(None, m2.groups()))

      else:

        nodes.append(nodestr)

    m = re_vol.match(line)

    if m:

      vols.append(m.group(1))

    m = re_drbdnode.match(line)

    if m:

      node = m.group(1)

      minor = int(m.group(2))

      if drbd_min.get(node) is not None:

        drbd_min[node].append(minor)

      else:

        drbd_min[node] = [minor]

  assert nodes

  assert len(nodes) < 2 or vols

  return {

    "nodes": nodes,

    "volumes": vols,

    "drbd-minors": drbd_min,

    }

def _DestroyInstanceVolumes(instance):

  """Remove all the LVM volumes of an instance.

  This is used to simulate HW errors (dead nodes, broken disks...); the

  configuration of the instance is not affected.

  @type instance: dictionary

  @param instance: the instance

  """

  info = _GetInstanceInfo(instance.name)

  vols = info["volumes"]

  for node in info["nodes"]:

    AssertCommand(["lvremove", "-f"] + vols, node=node)

def _GetInstanceField(instance, field):

  """Get the value of a field of an instance.

  @type instance: string

  @param instance: Instance name

  @type field: string

  @param field: Name of the field

  @rtype: string

  """

  master = qa_config.GetMasterNode()

  infocmd = utils.ShellQuoteArgs(["gnt-instance", "list", "--no-headers",

                                  "--units", "m", "-o", field, instance])

  return qa_utils.GetCommandOutput(master.primary, infocmd).strip()

def _GetBoolInstanceField(instance, field):

  """Get the Boolean value of a field of an instance.

  @type instance: string

  @param instance: Instance name

  @type field: string

  @param field: Name of the field

  @rtype: bool

  """

  info_out = _GetInstanceField(instance, field)

  if info_out == "Y":

    return True

  elif info_out == "N":

    return False

  else:

    raise qa_error.Error("Field %s of instance %s has a non-Boolean value:"

                         " %s" % (field, instance, info_out))

def _GetNumInstanceField(instance, field):

  """Get a numeric value of a field of an instance.

  @type instance: string

  @param instance: Instance name

  @type field: string

  @param field: Name of the field

  @rtype: int or float

  """

  info_out = _GetInstanceField(instance, field)

  try:

    ret = int(info_out)

  except ValueError:

    try:

      ret = float(info_out)

    except ValueError:

      raise qa_error.Error("Field %s of instance %s has a non-numeric value:"

                           " %s" % (field, instance, info_out))

  return ret

def GetInstanceSpec(instance, spec):

  """Return the current spec for the given parameter.

  @type instance: string

  @param instance: Instance name

  @type spec: string

  @param spec: one of the supported parameters: "mem-size", "cpu-count",

      "disk-count", "disk-size", "nic-count"

  @rtype: tuple

  @return: (minspec, maxspec); minspec and maxspec can be different only for

      memory and disk size

  """

  specmap = {

    "mem-size": ["be/minmem", "be/maxmem"],

    "cpu-count": ["vcpus"],

    "disk-count": ["disk.count"],

    "disk-size": ["disk.size/ "],

    "nic-count": ["nic.count"],

    }

  # For disks, first we need the number of disks

  if spec == "disk-size":

    (numdisk, _) = GetInstanceSpec(instance, "disk-count")

    fields = ["disk.size/%s" % k for k in range(0, numdisk)]

  else:

    assert spec in specmap, "%s not in %s" % (spec, specmap)

    fields = specmap[spec]

  values = [_GetNumInstanceField(instance, f) for f in fields]

  return (min(values), max(values))

def IsFailoverSupported(instance):

  return instance.disk_template in constants.DTS_MIRRORED

def IsMigrationSupported(instance):

  return instance.disk_template in constants.DTS_MIRRORED

def IsDiskReplacingSupported(instance):

  return instance.disk_template == constants.DT_DRBD8

def TestInstanceAddWithPlainDisk(nodes, fail=False):

  """gnt-instance add -t plain"""

  assert len(nodes) == 1

  instance = _DiskTest(nodes[0].primary, constants.DT_PLAIN, fail=fail)

  if not fail:

    qa_utils.RunInstanceCheck(instance, True)

  return instance

@InstanceCheck(None, INST_UP, RETURN_VALUE)

def TestInstanceAddWithDrbdDisk(nodes):

  """gnt-instance add -t drbd"""

  assert len(nodes) == 2

  return _DiskTest(":".join(map(operator.attrgetter("primary"), nodes)),

                   constants.DT_DRBD8)

@InstanceCheck(None, INST_UP, RETURN_VALUE)

def TestInstanceAddDiskless(nodes):

  """gnt-instance add -t diskless"""

  assert len(nodes) == 1

  return _DiskTest(nodes[0].primary, constants.DT_DISKLESS)

@InstanceCheck(None, INST_DOWN, FIRST_ARG)

def TestInstanceRemove(instance):

  """gnt-instance remove"""

  AssertCommand(["gnt-instance", "remove", "-f", instance.name])

@InstanceCheck(INST_DOWN, INST_UP, FIRST_ARG)

def TestInstanceStartup(instance):

  """gnt-instance startup"""

  AssertCommand(["gnt-instance", "startup", instance.name])

@InstanceCheck(INST_UP, INST_DOWN, FIRST_ARG)

def TestInstanceShutdown(instance):

  """gnt-instance shutdown"""

  AssertCommand(["gnt-instance", "shutdown", instance.name])

@InstanceCheck(INST_UP, INST_UP, FIRST_ARG)

def TestInstanceReboot(instance):

  """gnt-instance reboot"""

  options = qa_config.get("options", {})

  reboot_types = options.get("reboot-types", constants.REBOOT_TYPES)

  name = instance.name

  for rtype in reboot_types:

    AssertCommand(["gnt-instance", "reboot", "--type=%s" % rtype, name])

  AssertCommand(["gnt-instance", "shutdown", name])

  qa_utils.RunInstanceCheck(instance, False)

  AssertCommand(["gnt-instance", "reboot", name])

  master = qa_config.GetMasterNode()

  cmd = ["gnt-instance", "list", "--no-headers", "-o", "status", name]

  result_output = qa_utils.GetCommandOutput(master.primary,

                                            utils.ShellQuoteArgs(cmd))

  AssertEqual(result_output.strip(), constants.INSTST_RUNNING)

@InstanceCheck(INST_DOWN, INST_DOWN, FIRST_ARG)

def TestInstanceReinstall(instance):

  """gnt-instance reinstall"""

  if instance.disk_template == constants.DT_DISKLESS:

    print qa_utils.FormatInfo("Test not supported for diskless instances")

    return

  AssertCommand(["gnt-instance", "reinstall", "-f", instance.name])

  # Test with non-existant OS definition

  AssertCommand(["gnt-instance", "reinstall", "-f",

                 "--os-type=NonExistantOsForQa",

                 instance.name],

                fail=True)

def _ReadSsconfInstanceList():

  """Reads ssconf_instance_list from the master node.

  """

  master = qa_config.GetMasterNode()

  ssconf_path = utils.PathJoin(pathutils.DATA_DIR,

                               "ssconf_%s" % constants.SS_INSTANCE_LIST)

  cmd = ["cat", qa_utils.MakeNodePath(master, ssconf_path)]

  return qa_utils.GetCommandOutput(master.primary,

                                   utils.ShellQuoteArgs(cmd)).splitlines()

def _CheckSsconfInstanceList(instance):

  """Checks if a certain instance is in the ssconf instance list.

  @type instance: string

  @param instance: Instance name

  """

  AssertIn(qa_utils.ResolveInstanceName(instance),

           _ReadSsconfInstanceList())

@InstanceCheck(INST_DOWN, INST_DOWN, FIRST_ARG)

def TestInstanceRenameAndBack(rename_source, rename_target):

  """gnt-instance rename

  This must leave the instance with the original name, not the target

  name.

  """

  _CheckSsconfInstanceList(rename_source)

  # first do a rename to a different actual name, expecting it to fail

  qa_utils.AddToEtcHosts(["meeeeh-not-exists", rename_target])

  try:

    AssertCommand(["gnt-instance", "rename", rename_source, rename_target],

                  fail=True)

    _CheckSsconfInstanceList(rename_source)

  finally:

    qa_utils.RemoveFromEtcHosts(["meeeeh-not-exists", rename_target])

  # Check instance volume tags correctly updated

  # FIXME: this is LVM specific!

  info = _GetInstanceInfo(rename_source)

  tags_cmd = ("lvs -o tags --noheadings %s | grep " %

              (" ".join(info["volumes"]), ))

  # and now rename instance to rename_target...

  AssertCommand(["gnt-instance", "rename", rename_source, rename_target])

  _CheckSsconfInstanceList(rename_target)

  qa_utils.RunInstanceCheck(rename_source, False)

  qa_utils.RunInstanceCheck(rename_target, False)

  # NOTE: tags might not be the exactly as the instance name, due to

  # charset restrictions; hence the test might be flaky

  if rename_source != rename_target:

    for node in info["nodes"]:

      AssertCommand(tags_cmd + rename_source, node=node, fail=True)

      AssertCommand(tags_cmd + rename_target, node=node, fail=False)

  # and back

  AssertCommand(["gnt-instance", "rename", rename_target, rename_source])

  _CheckSsconfInstanceList(rename_source)

  qa_utils.RunInstanceCheck(rename_target, False)

  if rename_source != rename_target:

    for node in info["nodes"]:

      AssertCommand(tags_cmd + rename_source, node=node, fail=False)

      AssertCommand(tags_cmd + rename_target, node=node, fail=True)

@InstanceCheck(INST_UP, INST_UP, FIRST_ARG)

def TestInstanceFailover(instance):

  """gnt-instance failover"""

  if not IsFailoverSupported(instance):

    print qa_utils.FormatInfo("Instance doesn't support failover, skipping"

                              " test")

    return

  cmd = ["gnt-instance", "failover", "--force", instance.name]

  # failover ...

  AssertCommand(cmd)

  qa_utils.RunInstanceCheck(instance, True)

  # ... and back

  AssertCommand(cmd)

@InstanceCheck(INST_UP, INST_UP, FIRST_ARG)

def TestInstanceMigrate(instance, toggle_always_failover=True):

  """gnt-instance migrate"""

  if not IsMigrationSupported(instance):

    print qa_utils.FormatInfo("Instance doesn't support migration, skipping"

                              " test")

    return

  cmd = ["gnt-instance", "migrate", "--force", instance.name]

  af_par = constants.BE_ALWAYS_FAILOVER

  af_field = "be/" + constants.BE_ALWAYS_FAILOVER

  af_init_val = _GetBoolInstanceField(instance.name, af_field)

  # migrate ...

  AssertCommand(cmd)

  # TODO: Verify the choice between failover and migration

  qa_utils.RunInstanceCheck(instance, True)

  # ... and back (possibly with always_failover toggled)

  if toggle_always_failover:

    AssertCommand(["gnt-instance", "modify", "-B",

                   ("%s=%s" % (af_par, not af_init_val)),

                   instance.name])

  AssertCommand(cmd)

  # TODO: Verify the choice between failover and migration

  qa_utils.RunInstanceCheck(instance, True)

  if toggle_always_failover:

    AssertCommand(["gnt-instance", "modify", "-B",

                   ("%s=%s" % (af_par, af_init_val)), instance.name])

  # TODO: Split into multiple tests

  AssertCommand(["gnt-instance", "shutdown", instance.name])

  qa_utils.RunInstanceCheck(instance, False)

  AssertCommand(cmd, fail=True)

  AssertCommand(["gnt-instance", "migrate", "--force", "--allow-failover",

                 instance.name])

  AssertCommand(["gnt-instance", "start", instance.name])

  AssertCommand(cmd)

  # @InstanceCheck enforces the check that the instance is running

  qa_utils.RunInstanceCheck(instance, True)

  AssertCommand(["gnt-instance", "modify", "-B",

                 ("%s=%s" %

                  (constants.BE_ALWAYS_FAILOVER, constants.VALUE_TRUE)),

                 instance.name])

  AssertCommand(cmd)

  qa_utils.RunInstanceCheck(instance, True)

  # TODO: Verify that a failover has been done instead of a migration

  # TODO: Verify whether the default value is restored here (not hardcoded)

  AssertCommand(["gnt-instance", "modify", "-B",

                 ("%s=%s" %

                  (constants.BE_ALWAYS_FAILOVER, constants.VALUE_FALSE)),

                 instance.name])

  AssertCommand(cmd)

  qa_utils.RunInstanceCheck(instance, True)

def TestInstanceInfo(instance):

  """gnt-instance info"""

  AssertCommand(["gnt-instance", "info", instance.name])

@InstanceCheck(INST_UP, INST_UP, FIRST_ARG)

def TestInstanceModify(instance):

  """gnt-instance modify"""

  default_hv = qa_config.GetDefaultHypervisor()

  # Assume /sbin/init exists on all systems

  test_kernel = "/sbin/init"

  test_initrd = test_kernel

  orig_maxmem = qa_config.get(constants.BE_MAXMEM)

  orig_minmem = qa_config.get(constants.BE_MINMEM)

  #orig_bridge = qa_config.get("bridge", "xen-br0")

  args = [

    ["-B", "%s=128" % constants.BE_MINMEM],

    ["-B", "%s=128" % constants.BE_MAXMEM],

    ["-B", "%s=%s,%s=%s" % (constants.BE_MINMEM, orig_minmem,

                            constants.BE_MAXMEM, orig_maxmem)],

    ["-B", "%s=2" % constants.BE_VCPUS],

    ["-B", "%s=1" % constants.BE_VCPUS],

    ["-B", "%s=%s" % (constants.BE_VCPUS, constants.VALUE_DEFAULT)],

    ["-B", "%s=%s" % (constants.BE_ALWAYS_FAILOVER, constants.VALUE_TRUE)],

    ["-B", "%s=%s" % (constants.BE_ALWAYS_FAILOVER, constants.VALUE_DEFAULT)],

    ["-H", "%s=%s" % (constants.HV_KERNEL_PATH, test_kernel)],

    ["-H", "%s=%s" % (constants.HV_KERNEL_PATH, constants.VALUE_DEFAULT)],

    # TODO: bridge tests

    #["--bridge", "xen-br1"],

    #["--bridge", orig_bridge],

    ]

  if default_hv == constants.HT_XEN_PVM:

    args.extend([

      ["-H", "%s=%s" % (constants.HV_INITRD_PATH, test_initrd)],

      ["-H", "no_%s" % (constants.HV_INITRD_PATH, )],

      ["-H", "%s=%s" % (constants.HV_INITRD_PATH, constants.VALUE_DEFAULT)],

      ])

  elif default_hv == constants.HT_XEN_HVM:

    args.extend([

      ["-H", "%s=acn" % constants.HV_BOOT_ORDER],

      ["-H", "%s=%s" % (constants.HV_BOOT_ORDER, constants.VALUE_DEFAULT)],

      ])

  for alist in args:

    AssertCommand(["gnt-instance", "modify"] + alist + [instance.name])

  # check no-modify

  AssertCommand(["gnt-instance", "modify", instance.name], fail=True)

  # Marking offline while instance is running must fail...

  AssertCommand(["gnt-instance", "modify", "--offline", instance.name],

                 fail=True)

  # ...while making it online is ok, and should work

  AssertCommand(["gnt-instance", "modify", "--online", instance.name])

@InstanceCheck(INST_DOWN, INST_DOWN, FIRST_ARG)

def TestInstanceStoppedModify(instance):

  """gnt-instance modify (stopped instance)"""

  name = instance.name

  # Instance was not marked offline; try marking it online once more

  AssertCommand(["gnt-instance", "modify", "--online", name])

  # Mark instance as offline

  AssertCommand(["gnt-instance", "modify", "--offline", name])

  # When the instance is offline shutdown should only work with --force,

  # while start should never work

  AssertCommand(["gnt-instance", "shutdown", name], fail=True)

  AssertCommand(["gnt-instance", "shutdown", "--force", name])

  AssertCommand(["gnt-instance", "start", name], fail=True)

  AssertCommand(["gnt-instance", "start", "--force", name], fail=True)

  # Also do offline to offline

  AssertCommand(["gnt-instance", "modify", "--offline", name])

  # And online again

  AssertCommand(["gnt-instance", "modify", "--online", name])

@InstanceCheck(INST_DOWN, INST_DOWN, FIRST_ARG)

def TestInstanceConvertDiskToPlain(instance, inodes):

  """gnt-instance modify -t"""

  name = instance.name

  template = instance.disk_template

  if template != constants.DT_DRBD8:

    print qa_utils.FormatInfo("Unsupported template %s, skipping conversion"

                              " test" % template)

    return

  assert len(inodes) == 2

  AssertCommand(["gnt-instance", "modify", "-t", constants.DT_PLAIN, name])

  AssertCommand(["gnt-instance", "modify", "-t", constants.DT_DRBD8,

                 "-n", inodes[1].primary, name])

@InstanceCheck(INST_DOWN, INST_DOWN, FIRST_ARG)

def TestInstanceGrowDisk(instance):

  """gnt-instance grow-disk"""

  if qa_config.GetExclusiveStorage():

    print qa_utils.FormatInfo("Test not supported with exclusive_storage")

    return

  if instance.disk_template == constants.DT_DISKLESS:

    print qa_utils.FormatInfo("Test not supported for diskless instances")

    return

  name = instance.name

  all_size = qa_config.get("disk")

  all_grow = qa_config.get("disk-growth")

  if not all_grow:

    # missing disk sizes but instance grow disk has been enabled,

    # let's set fixed/nomimal growth

    all_grow = ["128M" for _ in all_size]

  for idx, (size, grow) in enumerate(zip(all_size, all_grow)):

    # succeed in grow by amount

    AssertCommand(["gnt-instance", "grow-disk", name, str(idx), grow])

    # fail in grow to the old size

    AssertCommand(["gnt-instance", "grow-disk", "--absolute", name, str(idx),

                   size], fail=True)

    # succeed to grow to old size + 2 * growth

    int_size = utils.ParseUnit(size)

    int_grow = utils.ParseUnit(grow)

    AssertCommand(["gnt-instance", "grow-disk", "--absolute", name, str(idx),

                   str(int_size + 2 * int_grow)])

def TestInstanceList():

  """gnt-instance list"""

  qa_utils.GenericQueryTest("gnt-instance", query.INSTANCE_FIELDS.keys())

def TestInstanceListFields():

  """gnt-instance list-fields"""

  qa_utils.GenericQueryFieldsTest("gnt-instance", query.INSTANCE_FIELDS.keys())

@InstanceCheck(INST_UP, INST_UP, FIRST_ARG)

def TestInstanceConsole(instance):

  """gnt-instance console"""

  AssertCommand(["gnt-instance", "console", "--show-cmd", instance.name])

@InstanceCheck(INST_UP, INST_UP, FIRST_ARG)

def TestReplaceDisks(instance, curr_nodes, other_nodes):

  """gnt-instance replace-disks"""

  def buildcmd(args):

    cmd = ["gnt-instance", "replace-disks"]

    cmd.extend(args)

    cmd.append(instance.name)

    return cmd

  if not IsDiskReplacingSupported(instance):

    print qa_utils.FormatInfo("Instance doesn't support disk replacing,"

                              " skipping test")

    return

  # Currently all supported templates have one primary and one secondary node

  assert len(curr_nodes) == 2

  snode = curr_nodes[1]

  assert len(other_nodes) == 1

  othernode = other_nodes[0]

  options = qa_config.get("options", {})

  use_ialloc = options.get("use-iallocators", True)

  for data in [

    ["-p"],

    ["-s"],

    # A placeholder; the actual command choice depends on use_ialloc

    None,

    # Restore the original secondary

    ["--new-secondary=%s" % snode.primary],

    ]:

    if data is None:

      if use_ialloc:

        data = ["-I", constants.DEFAULT_IALLOCATOR_SHORTCUT]

      else:

        data = ["--new-secondary=%s" % othernode.primary]

    AssertCommand(buildcmd(data))

  AssertCommand(buildcmd(["-a"]))

  AssertCommand(["gnt-instance", "stop", instance.name])

  AssertCommand(buildcmd(["-a"]), fail=True)

  AssertCommand(["gnt-instance", "activate-disks", instance.name])

  AssertCommand(["gnt-instance", "activate-disks", "--wait-for-sync",

                 instance.name])

  AssertCommand(buildcmd(["-a"]))

  AssertCommand(["gnt-instance", "start", instance.name])

def _AssertRecreateDisks(cmdargs, instance, fail=False, check=True,

                         destroy=True):

  """Execute gnt-instance recreate-disks and check the result

  @param cmdargs: Arguments (instance name excluded)

  @param instance: Instance to operate on

  @param fail: True if the command is expected to fail

  @param check: If True and fail is False, check that the disks work

  @prama destroy: If True, destroy the old disks first

  """

  if destroy:

    _DestroyInstanceVolumes(instance)

  AssertCommand((["gnt-instance", "recreate-disks"] + cmdargs +

                 [instance.name]), fail)

  if not fail and check:

    # Quick check that the disks are there

    AssertCommand(["gnt-instance", "activate-disks", instance.name])

    AssertCommand(["gnt-instance", "activate-disks", "--wait-for-sync",

                   instance.name])

    AssertCommand(["gnt-instance", "deactivate-disks", instance.name])

@InstanceCheck(INST_UP, INST_UP, FIRST_ARG)