cmdlib.py 154 KB
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#
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#

# Copyright (C) 2006, 2007 Google Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA.


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"""Module implementing the master-side code."""
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# pylint: disable-msg=W0613,W0201

import os
import os.path
import sha
import time
import tempfile
import re
import platform

from ganeti import rpc
from ganeti import ssh
from ganeti import logger
from ganeti import utils
from ganeti import errors
from ganeti import hypervisor
from ganeti import config
from ganeti import constants
from ganeti import objects
from ganeti import opcodes
from ganeti import ssconf

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class LogicalUnit(object):
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  """Logical Unit base class.
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  Subclasses must follow these rules:
    - implement CheckPrereq which also fills in the opcode instance
      with all the fields (even if as None)
    - implement Exec
    - implement BuildHooksEnv
    - redefine HPATH and HTYPE
    - optionally redefine their run requirements (REQ_CLUSTER,
      REQ_MASTER); note that all commands require root permissions

  """
  HPATH = None
  HTYPE = None
  _OP_REQP = []
  REQ_CLUSTER = True
  REQ_MASTER = True

  def __init__(self, processor, op, cfg, sstore):
    """Constructor for LogicalUnit.

    This needs to be overriden in derived classes in order to check op
    validity.

    """
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    self.proc = processor
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    self.op = op
    self.cfg = cfg
    self.sstore = sstore
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    self.__ssh = None

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    for attr_name in self._OP_REQP:
      attr_val = getattr(op, attr_name, None)
      if attr_val is None:
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        raise errors.OpPrereqError("Required parameter '%s' missing" %
                                   attr_name)
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    if self.REQ_CLUSTER:
      if not cfg.IsCluster():
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        raise errors.OpPrereqError("Cluster not initialized yet,"
                                   " use 'gnt-cluster init' first.")
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      if self.REQ_MASTER:
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        master = sstore.GetMasterNode()
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        if master != utils.HostInfo().name:
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          raise errors.OpPrereqError("Commands must be run on the master"
                                     " node %s" % master)
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  def __GetSSH(self):
    """Returns the SshRunner object

    """
    if not self.__ssh:
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      self.__ssh = ssh.SshRunner(self.sstore)
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    return self.__ssh

  ssh = property(fget=__GetSSH)

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  def CheckPrereq(self):
    """Check prerequisites for this LU.

    This method should check that the prerequisites for the execution
    of this LU are fulfilled. It can do internode communication, but
    it should be idempotent - no cluster or system changes are
    allowed.

    The method should raise errors.OpPrereqError in case something is
    not fulfilled. Its return value is ignored.

    This method should also update all the parameters of the opcode to
    their canonical form; e.g. a short node name must be fully
    expanded after this method has successfully completed (so that
    hooks, logging, etc. work correctly).

    """
    raise NotImplementedError

  def Exec(self, feedback_fn):
    """Execute the LU.

    This method should implement the actual work. It should raise
    errors.OpExecError for failures that are somewhat dealt with in
    code, or expected.

    """
    raise NotImplementedError

  def BuildHooksEnv(self):
    """Build hooks environment for this LU.

    This method should return a three-node tuple consisting of: a dict
    containing the environment that will be used for running the
    specific hook for this LU, a list of node names on which the hook
    should run before the execution, and a list of node names on which
    the hook should run after the execution.

    The keys of the dict must not have 'GANETI_' prefixed as this will
    be handled in the hooks runner. Also note additional keys will be
    added by the hooks runner. If the LU doesn't define any
    environment, an empty dict (and not None) should be returned.

    As for the node lists, the master should not be included in the
    them, as it will be added by the hooks runner in case this LU
    requires a cluster to run on (otherwise we don't have a node
    list). No nodes should be returned as an empty list (and not
    None).

    Note that if the HPATH for a LU class is None, this function will
    not be called.

    """
    raise NotImplementedError


class NoHooksLU(LogicalUnit):
  """Simple LU which runs no hooks.

  This LU is intended as a parent for other LogicalUnits which will
  run no hooks, in order to reduce duplicate code.

  """
  HPATH = None
  HTYPE = None

  def BuildHooksEnv(self):
    """Build hooks env.

    This is a no-op, since we don't run hooks.

    """
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    return {}, [], []
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def _AddHostToEtcHosts(hostname):
  """Wrapper around utils.SetEtcHostsEntry.

  """
  hi = utils.HostInfo(name=hostname)
  utils.SetEtcHostsEntry(constants.ETC_HOSTS, hi.ip, hi.name, [hi.ShortName()])


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def _RemoveHostFromEtcHosts(hostname):
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  """Wrapper around utils.RemoveEtcHostsEntry.
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  """
  hi = utils.HostInfo(name=hostname)
  utils.RemoveEtcHostsEntry(constants.ETC_HOSTS, hi.name)
  utils.RemoveEtcHostsEntry(constants.ETC_HOSTS, hi.ShortName())


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def _GetWantedNodes(lu, nodes):
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  """Returns list of checked and expanded node names.
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  Args:
    nodes: List of nodes (strings) or None for all

  """
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  if not isinstance(nodes, list):
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    raise errors.OpPrereqError("Invalid argument type 'nodes'")
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  if nodes:
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    wanted = []
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    for name in nodes:
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      node = lu.cfg.ExpandNodeName(name)
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      if node is None:
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        raise errors.OpPrereqError("No such node name '%s'" % name)
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      wanted.append(node)
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  else:
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    wanted = lu.cfg.GetNodeList()
  return utils.NiceSort(wanted)
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def _GetWantedInstances(lu, instances):
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  """Returns list of checked and expanded instance names.
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  Args:
    instances: List of instances (strings) or None for all

  """
  if not isinstance(instances, list):
    raise errors.OpPrereqError("Invalid argument type 'instances'")

  if instances:
    wanted = []

    for name in instances:
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      instance = lu.cfg.ExpandInstanceName(name)
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      if instance is None:
        raise errors.OpPrereqError("No such instance name '%s'" % name)
      wanted.append(instance)

  else:
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    wanted = lu.cfg.GetInstanceList()
  return utils.NiceSort(wanted)
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def _CheckOutputFields(static, dynamic, selected):
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  """Checks whether all selected fields are valid.

  Args:
    static: Static fields
    dynamic: Dynamic fields

  """
  static_fields = frozenset(static)
  dynamic_fields = frozenset(dynamic)
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  all_fields = static_fields | dynamic_fields
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  if not all_fields.issuperset(selected):
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    raise errors.OpPrereqError("Unknown output fields selected: %s"
                               % ",".join(frozenset(selected).
                                          difference(all_fields)))
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def _BuildInstanceHookEnv(name, primary_node, secondary_nodes, os_type, status,
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                          memory, vcpus, nics):
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  """Builds instance related env variables for hooks from single variables.

  Args:
    secondary_nodes: List of secondary nodes as strings
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  """
  env = {
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    "OP_TARGET": name,
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    "INSTANCE_NAME": name,
    "INSTANCE_PRIMARY": primary_node,
    "INSTANCE_SECONDARIES": " ".join(secondary_nodes),
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    "INSTANCE_OS_TYPE": os_type,
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    "INSTANCE_STATUS": status,
    "INSTANCE_MEMORY": memory,
    "INSTANCE_VCPUS": vcpus,
  }

  if nics:
    nic_count = len(nics)
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    for idx, (ip, bridge, mac) in enumerate(nics):
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      if ip is None:
        ip = ""
      env["INSTANCE_NIC%d_IP" % idx] = ip
      env["INSTANCE_NIC%d_BRIDGE" % idx] = bridge
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      env["INSTANCE_NIC%d_HWADDR" % idx] = mac
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  else:
    nic_count = 0

  env["INSTANCE_NIC_COUNT"] = nic_count

  return env


def _BuildInstanceHookEnvByObject(instance, override=None):
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  """Builds instance related env variables for hooks from an object.

  Args:
    instance: objects.Instance object of instance
    override: dict of values to override
  """
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  args = {
    'name': instance.name,
    'primary_node': instance.primary_node,
    'secondary_nodes': instance.secondary_nodes,
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    'os_type': instance.os,
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    'status': instance.os,
    'memory': instance.memory,
    'vcpus': instance.vcpus,
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    'nics': [(nic.ip, nic.bridge, nic.mac) for nic in instance.nics],
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  }
  if override:
    args.update(override)
  return _BuildInstanceHookEnv(**args)


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def _UpdateKnownHosts(fullnode, ip, pubkey):
  """Ensure a node has a correct known_hosts entry.

  Args:
    fullnode - Fully qualified domain name of host. (str)
    ip       - IPv4 address of host (str)
    pubkey   - the public key of the cluster

  """
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  if os.path.exists(constants.SSH_KNOWN_HOSTS_FILE):
    f = open(constants.SSH_KNOWN_HOSTS_FILE, 'r+')
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  else:
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    f = open(constants.SSH_KNOWN_HOSTS_FILE, 'w+')
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  inthere = False

  save_lines = []
  add_lines = []
  removed = False

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  for rawline in f:
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    logger.Debug('read %s' % (repr(rawline),))

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    parts = rawline.rstrip('\r\n').split()

    # Ignore unwanted lines
    if len(parts) >= 3 and not rawline.lstrip()[0] == '#':
      fields = parts[0].split(',')
      key = parts[2]

      haveall = True
      havesome = False
      for spec in [ ip, fullnode ]:
        if spec not in fields:
          haveall = False
        if spec in fields:
          havesome = True

      logger.Debug("key, pubkey = %s." % (repr((key, pubkey)),))
      if haveall and key == pubkey:
        inthere = True
        save_lines.append(rawline)
        logger.Debug("Keeping known_hosts '%s'." % (repr(rawline),))
        continue

      if havesome and (not haveall or key != pubkey):
        removed = True
        logger.Debug("Discarding known_hosts '%s'." % (repr(rawline),))
        continue
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    save_lines.append(rawline)

  if not inthere:
    add_lines.append('%s,%s ssh-rsa %s\n' % (fullnode, ip, pubkey))
    logger.Debug("Adding known_hosts '%s'." % (repr(add_lines[-1]),))

  if removed:
    save_lines = save_lines + add_lines

    # Write a new file and replace old.
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    fd, tmpname = tempfile.mkstemp('.tmp', 'known_hosts.',
                                   constants.DATA_DIR)
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    newfile = os.fdopen(fd, 'w')
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    try:
      newfile.write(''.join(save_lines))
    finally:
      newfile.close()
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    logger.Debug("Wrote new known_hosts.")
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    os.rename(tmpname, constants.SSH_KNOWN_HOSTS_FILE)
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  elif add_lines:
    # Simply appending a new line will do the trick.
    f.seek(0, 2)
    for add in add_lines:
      f.write(add)

  f.close()


def _HasValidVG(vglist, vgname):
  """Checks if the volume group list is valid.

  A non-None return value means there's an error, and the return value
  is the error message.

  """
  vgsize = vglist.get(vgname, None)
  if vgsize is None:
    return "volume group '%s' missing" % vgname
  elif vgsize < 20480:
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    return ("volume group '%s' too small (20480MiB required, %dMib found)" %
            (vgname, vgsize))
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  return None


def _InitSSHSetup(node):
  """Setup the SSH configuration for the cluster.


  This generates a dsa keypair for root, adds the pub key to the
  permitted hosts and adds the hostkey to its own known hosts.

  Args:
    node: the name of this host as a fqdn

  """
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  priv_key, pub_key, auth_keys = ssh.GetUserFiles(constants.GANETI_RUNAS)
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  for name in priv_key, pub_key:
    if os.path.exists(name):
      utils.CreateBackup(name)
    utils.RemoveFile(name)
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  result = utils.RunCmd(["ssh-keygen", "-t", "dsa",
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                         "-f", priv_key,
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                         "-q", "-N", ""])
  if result.failed:
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    raise errors.OpExecError("Could not generate ssh keypair, error %s" %
                             result.output)
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  f = open(pub_key, 'r')
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  try:
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    utils.AddAuthorizedKey(auth_keys, f.read(8192))
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  finally:
    f.close()


def _InitGanetiServerSetup(ss):
  """Setup the necessary configuration for the initial node daemon.

  This creates the nodepass file containing the shared password for
  the cluster and also generates the SSL certificate.

  """
  # Create pseudo random password
  randpass = sha.new(os.urandom(64)).hexdigest()
  # and write it into sstore
  ss.SetKey(ss.SS_NODED_PASS, randpass)

  result = utils.RunCmd(["openssl", "req", "-new", "-newkey", "rsa:1024",
                         "-days", str(365*5), "-nodes", "-x509",
                         "-keyout", constants.SSL_CERT_FILE,
                         "-out", constants.SSL_CERT_FILE, "-batch"])
  if result.failed:
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    raise errors.OpExecError("could not generate server ssl cert, command"
                             " %s had exitcode %s and error message %s" %
                             (result.cmd, result.exit_code, result.output))
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  os.chmod(constants.SSL_CERT_FILE, 0400)

  result = utils.RunCmd([constants.NODE_INITD_SCRIPT, "restart"])

  if result.failed:
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    raise errors.OpExecError("Could not start the node daemon, command %s"
                             " had exitcode %s and error %s" %
                             (result.cmd, result.exit_code, result.output))
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def _CheckInstanceBridgesExist(instance):
  """Check that the brigdes needed by an instance exist.

  """
  # check bridges existance
  brlist = [nic.bridge for nic in instance.nics]
  if not rpc.call_bridges_exist(instance.primary_node, brlist):
    raise errors.OpPrereqError("one or more target bridges %s does not"
                               " exist on destination node '%s'" %
                               (brlist, instance.primary_node))


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class LUInitCluster(LogicalUnit):
  """Initialise the cluster.

  """
  HPATH = "cluster-init"
  HTYPE = constants.HTYPE_CLUSTER
  _OP_REQP = ["cluster_name", "hypervisor_type", "vg_name", "mac_prefix",
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              "def_bridge", "master_netdev"]
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  REQ_CLUSTER = False

  def BuildHooksEnv(self):
    """Build hooks env.

    Notes: Since we don't require a cluster, we must manually add
    ourselves in the post-run node list.

    """
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    env = {"OP_TARGET": self.op.cluster_name}
    return env, [], [self.hostname.name]
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  def CheckPrereq(self):
    """Verify that the passed name is a valid one.

    """
    if config.ConfigWriter.IsCluster():
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      raise errors.OpPrereqError("Cluster is already initialised")
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    if self.op.hypervisor_type == constants.HT_XEN_HVM31:
      if not os.path.exists(constants.VNC_PASSWORD_FILE):
        raise errors.OpPrereqError("Please prepare the cluster VNC"
                                   "password file %s" %
                                   constants.VNC_PASSWORD_FILE)

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    self.hostname = hostname = utils.HostInfo()
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    if hostname.ip.startswith("127."):
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      raise errors.OpPrereqError("This host's IP resolves to the private"
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                                 " range (%s). Please fix DNS or %s." %
                                 (hostname.ip, constants.ETC_HOSTS))
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    if not utils.TcpPing(hostname.ip, constants.DEFAULT_NODED_PORT,
                         source=constants.LOCALHOST_IP_ADDRESS):
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      raise errors.OpPrereqError("Inconsistency: this host's name resolves"
                                 " to %s,\nbut this ip address does not"
                                 " belong to this host."
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                                 " Aborting." % hostname.ip)
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    self.clustername = clustername = utils.HostInfo(self.op.cluster_name)

    if utils.TcpPing(clustername.ip, constants.DEFAULT_NODED_PORT,
                     timeout=5):
      raise errors.OpPrereqError("Cluster IP already active. Aborting.")

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    secondary_ip = getattr(self.op, "secondary_ip", None)
    if secondary_ip and not utils.IsValidIP(secondary_ip):
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      raise errors.OpPrereqError("Invalid secondary ip given")
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    if (secondary_ip and
        secondary_ip != hostname.ip and
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        (not utils.TcpPing(secondary_ip, constants.DEFAULT_NODED_PORT,
                           source=constants.LOCALHOST_IP_ADDRESS))):
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      raise errors.OpPrereqError("You gave %s as secondary IP,"
                                 " but it does not belong to this host." %
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                                 secondary_ip)
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    self.secondary_ip = secondary_ip

    # checks presence of the volume group given
    vgstatus = _HasValidVG(utils.ListVolumeGroups(), self.op.vg_name)

    if vgstatus:
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      raise errors.OpPrereqError("Error: %s" % vgstatus)
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    if not re.match("^[0-9a-z]{2}:[0-9a-z]{2}:[0-9a-z]{2}$",
                    self.op.mac_prefix):
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      raise errors.OpPrereqError("Invalid mac prefix given '%s'" %
                                 self.op.mac_prefix)
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    if self.op.hypervisor_type not in constants.HYPER_TYPES:
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      raise errors.OpPrereqError("Invalid hypervisor type given '%s'" %
                                 self.op.hypervisor_type)
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    result = utils.RunCmd(["ip", "link", "show", "dev", self.op.master_netdev])
    if result.failed:
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      raise errors.OpPrereqError("Invalid master netdev given (%s): '%s'" %
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                                 (self.op.master_netdev,
                                  result.output.strip()))
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    if not (os.path.isfile(constants.NODE_INITD_SCRIPT) and
            os.access(constants.NODE_INITD_SCRIPT, os.X_OK)):
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      raise errors.OpPrereqError("Init.d script '%s' missing or not"
                                 " executable." % constants.NODE_INITD_SCRIPT)
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  def Exec(self, feedback_fn):
    """Initialize the cluster.

    """
    clustername = self.clustername
    hostname = self.hostname

    # set up the simple store
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    self.sstore = ss = ssconf.SimpleStore()
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    ss.SetKey(ss.SS_HYPERVISOR, self.op.hypervisor_type)
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    ss.SetKey(ss.SS_MASTER_NODE, hostname.name)
    ss.SetKey(ss.SS_MASTER_IP, clustername.ip)
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    ss.SetKey(ss.SS_MASTER_NETDEV, self.op.master_netdev)
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    ss.SetKey(ss.SS_CLUSTER_NAME, clustername.name)
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    # set up the inter-node password and certificate
    _InitGanetiServerSetup(ss)

    # start the master ip
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    rpc.call_node_start_master(hostname.name)
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    # set up ssh config and /etc/hosts
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    f = open(constants.SSH_HOST_RSA_PUB, 'r')
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    try:
      sshline = f.read()
    finally:
      f.close()
    sshkey = sshline.split(" ")[1]

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    _AddHostToEtcHosts(hostname.name)
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    _UpdateKnownHosts(hostname.name, hostname.ip, sshkey)
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    _InitSSHSetup(hostname.name)
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    # init of cluster config file
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    self.cfg = cfgw = config.ConfigWriter()
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    cfgw.InitConfig(hostname.name, hostname.ip, self.secondary_ip,
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                    sshkey, self.op.mac_prefix,
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                    self.op.vg_name, self.op.def_bridge)


class LUDestroyCluster(NoHooksLU):
  """Logical unit for destroying the cluster.

  """
  _OP_REQP = []

  def CheckPrereq(self):
    """Check prerequisites.

    This checks whether the cluster is empty.

    Any errors are signalled by raising errors.OpPrereqError.

    """
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    master = self.sstore.GetMasterNode()
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    nodelist = self.cfg.GetNodeList()
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    if len(nodelist) != 1 or nodelist[0] != master:
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      raise errors.OpPrereqError("There are still %d node(s) in"
                                 " this cluster." % (len(nodelist) - 1))
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    instancelist = self.cfg.GetInstanceList()
    if instancelist:
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      raise errors.OpPrereqError("There are still %d instance(s) in"
                                 " this cluster." % len(instancelist))
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  def Exec(self, feedback_fn):
    """Destroys the cluster.

    """
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    master = self.sstore.GetMasterNode()
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    if not rpc.call_node_stop_master(master):
      raise errors.OpExecError("Could not disable the master role")
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    priv_key, pub_key, _ = ssh.GetUserFiles(constants.GANETI_RUNAS)
    utils.CreateBackup(priv_key)
    utils.CreateBackup(pub_key)
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    rpc.call_node_leave_cluster(master)
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class LUVerifyCluster(NoHooksLU):
  """Verifies the cluster status.

  """
  _OP_REQP = []

  def _VerifyNode(self, node, file_list, local_cksum, vglist, node_result,
                  remote_version, feedback_fn):
    """Run multiple tests against a node.

    Test list:
      - compares ganeti version
      - checks vg existance and size > 20G
      - checks config file checksum
      - checks ssh to other nodes

    Args:
      node: name of the node to check
      file_list: required list of files
      local_cksum: dictionary of local files and their checksums
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    """
    # compares ganeti version
    local_version = constants.PROTOCOL_VERSION
    if not remote_version:
      feedback_fn(" - ERROR: connection to %s failed" % (node))
      return True

    if local_version != remote_version:
      feedback_fn("  - ERROR: sw version mismatch: master %s, node(%s) %s" %
                      (local_version, node, remote_version))
      return True

    # checks vg existance and size > 20G

    bad = False
    if not vglist:
      feedback_fn("  - ERROR: unable to check volume groups on node %s." %
                      (node,))
      bad = True
    else:
      vgstatus = _HasValidVG(vglist, self.cfg.GetVGName())
      if vgstatus:
        feedback_fn("  - ERROR: %s on node %s" % (vgstatus, node))
        bad = True

    # checks config file checksum
    # checks ssh to any

    if 'filelist' not in node_result:
      bad = True
      feedback_fn("  - ERROR: node hasn't returned file checksum data")
    else:
      remote_cksum = node_result['filelist']
      for file_name in file_list:
        if file_name not in remote_cksum:
          bad = True
          feedback_fn("  - ERROR: file '%s' missing" % file_name)
        elif remote_cksum[file_name] != local_cksum[file_name]:
          bad = True
          feedback_fn("  - ERROR: file '%s' has wrong checksum" % file_name)

    if 'nodelist' not in node_result:
      bad = True
      feedback_fn("  - ERROR: node hasn't returned node connectivity data")
    else:
      if node_result['nodelist']:
        bad = True
        for node in node_result['nodelist']:
          feedback_fn("  - ERROR: communication with node '%s': %s" %
                          (node, node_result['nodelist'][node]))
    hyp_result = node_result.get('hypervisor', None)
    if hyp_result is not None:
      feedback_fn("  - ERROR: hypervisor verify failure: '%s'" % hyp_result)
    return bad

  def _VerifyInstance(self, instance, node_vol_is, node_instance, feedback_fn):
    """Verify an instance.

    This function checks to see if the required block devices are
    available on the instance's node.

    """
    bad = False

    instancelist = self.cfg.GetInstanceList()
    if not instance in instancelist:
      feedback_fn("  - ERROR: instance %s not in instance list %s" %
                      (instance, instancelist))
      bad = True

    instanceconfig = self.cfg.GetInstanceInfo(instance)
    node_current = instanceconfig.primary_node

    node_vol_should = {}
    instanceconfig.MapLVsByNode(node_vol_should)

    for node in node_vol_should:
      for volume in node_vol_should[node]:
        if node not in node_vol_is or volume not in node_vol_is[node]:
          feedback_fn("  - ERROR: volume %s missing on node %s" %
                          (volume, node))
          bad = True

    if not instanceconfig.status == 'down':
      if not instance in node_instance[node_current]:
        feedback_fn("  - ERROR: instance %s not running on node %s" %
                        (instance, node_current))
        bad = True

    for node in node_instance:
      if (not node == node_current):
        if instance in node_instance[node]:
          feedback_fn("  - ERROR: instance %s should not run on node %s" %
                          (instance, node))
          bad = True

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    return bad
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  def _VerifyOrphanVolumes(self, node_vol_should, node_vol_is, feedback_fn):
    """Verify if there are any unknown volumes in the cluster.

    The .os, .swap and backup volumes are ignored. All other volumes are
    reported as unknown.

    """
    bad = False

    for node in node_vol_is:
      for volume in node_vol_is[node]:
        if node not in node_vol_should or volume not in node_vol_should[node]:
          feedback_fn("  - ERROR: volume %s on node %s should not exist" %
                      (volume, node))
          bad = True
    return bad

  def _VerifyOrphanInstances(self, instancelist, node_instance, feedback_fn):
    """Verify the list of running instances.

    This checks what instances are running but unknown to the cluster.

    """
    bad = False
    for node in node_instance:
      for runninginstance in node_instance[node]:
        if runninginstance not in instancelist:
          feedback_fn("  - ERROR: instance %s on node %s should not exist" %
                          (runninginstance, node))
          bad = True
    return bad

  def CheckPrereq(self):
    """Check prerequisites.

    This has no prerequisites.

    """
    pass

  def Exec(self, feedback_fn):
    """Verify integrity of cluster, performing various test on nodes.

    """
    bad = False
    feedback_fn("* Verifying global settings")
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    for msg in self.cfg.VerifyConfig():
      feedback_fn("  - ERROR: %s" % msg)
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    vg_name = self.cfg.GetVGName()
    nodelist = utils.NiceSort(self.cfg.GetNodeList())
    instancelist = utils.NiceSort(self.cfg.GetInstanceList())
    node_volume = {}
    node_instance = {}

    # FIXME: verify OS list
    # do local checksums
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    file_names = list(self.sstore.GetFileList())
    file_names.append(constants.SSL_CERT_FILE)
    file_names.append(constants.CLUSTER_CONF_FILE)
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    local_checksums = utils.FingerprintFiles(file_names)

    feedback_fn("* Gathering data (%d nodes)" % len(nodelist))
    all_volumeinfo = rpc.call_volume_list(nodelist, vg_name)
    all_instanceinfo = rpc.call_instance_list(nodelist)
    all_vglist = rpc.call_vg_list(nodelist)
    node_verify_param = {
      'filelist': file_names,
      'nodelist': nodelist,
      'hypervisor': None,
      }
    all_nvinfo = rpc.call_node_verify(nodelist, node_verify_param)
    all_rversion = rpc.call_version(nodelist)

    for node in nodelist:
      feedback_fn("* Verifying node %s" % node)
      result = self._VerifyNode(node, file_names, local_checksums,
                                all_vglist[node], all_nvinfo[node],
                                all_rversion[node], feedback_fn)
      bad = bad or result

      # node_volume
      volumeinfo = all_volumeinfo[node]

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      if isinstance(volumeinfo, basestring):
        feedback_fn("  - ERROR: LVM problem on node %s: %s" %
                    (node, volumeinfo[-400:].encode('string_escape')))
        bad = True
        node_volume[node] = {}
      elif not isinstance(volumeinfo, dict):
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        feedback_fn("  - ERROR: connection to %s failed" % (node,))
        bad = True
        continue
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      else:
        node_volume[node] = volumeinfo
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      # node_instance
      nodeinstance = all_instanceinfo[node]
      if type(nodeinstance) != list:
        feedback_fn("  - ERROR: connection to %s failed" % (node,))
        bad = True
        continue

      node_instance[node] = nodeinstance

    node_vol_should = {}

    for instance in instancelist:
      feedback_fn("* Verifying instance %s" % instance)
      result =  self._VerifyInstance(instance, node_volume, node_instance,
                                     feedback_fn)
      bad = bad or result

      inst_config = self.cfg.GetInstanceInfo(instance)

      inst_config.MapLVsByNode(node_vol_should)

    feedback_fn("* Verifying orphan volumes")
    result = self._VerifyOrphanVolumes(node_vol_should, node_volume,
                                       feedback_fn)
    bad = bad or result

    feedback_fn("* Verifying remaining instances")
    result = self._VerifyOrphanInstances(instancelist, node_instance,
                                         feedback_fn)
    bad = bad or result

    return int(bad)


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class LUVerifyDisks(NoHooksLU):
  """Verifies the cluster disks status.

  """
  _OP_REQP = []

  def CheckPrereq(self):
    """Check prerequisites.

    This has no prerequisites.

    """
    pass

  def Exec(self, feedback_fn):
    """Verify integrity of cluster disks.

    """
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    result = res_nodes, res_nlvm, res_instances, res_missing = [], {}, [], {}
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    vg_name = self.cfg.GetVGName()
    nodes = utils.NiceSort(self.cfg.GetNodeList())
    instances = [self.cfg.GetInstanceInfo(name)
                 for name in self.cfg.GetInstanceList()]

    nv_dict = {}
    for inst in instances:
      inst_lvs = {}
      if (inst.status != "up" or
          inst.disk_template not in constants.DTS_NET_MIRROR):
        continue
      inst.MapLVsByNode(inst_lvs)
      # transform { iname: {node: [vol,],},} to {(node, vol): iname}
      for node, vol_list in inst_lvs.iteritems():
        for vol in vol_list:
          nv_dict[(node, vol)] = inst

    if not nv_dict:
      return result

    node_lvs = rpc.call_volume_list(nodes, vg_name)

    to_act = set()
    for node in nodes:
      # node_volume
      lvs = node_lvs[node]

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      if isinstance(lvs, basestring):
        logger.Info("error enumerating LVs on node %s: %s" % (node, lvs))
        res_nlvm[node] = lvs
      elif not isinstance(lvs, dict):
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        logger.Info("connection to node %s failed or invalid data returned" %
                    (node,))
        res_nodes.append(node)
        continue

      for lv_name, (_, lv_inactive, lv_online) in lvs.iteritems():
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        inst = nv_dict.pop((node, lv_name), None)
        if (not lv_online and inst is not None
            and inst.name not in res_instances):
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          res_instances.append(inst.name)
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    # any leftover items in nv_dict are missing LVs, let's arrange the
    # data better
    for key, inst in nv_dict.iteritems():
      if inst.name not in res_missing:
        res_missing[inst.name] = []
      res_missing[inst.name].append(key)

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    return result


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class LURenameCluster(LogicalUnit):
  """Rename the cluster.

  """
  HPATH = "cluster-rename"
  HTYPE = constants.HTYPE_CLUSTER
  _OP_REQP = ["name"]

  def BuildHooksEnv(self):
    """Build hooks env.

    """
    env = {
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      "OP_TARGET": self.sstore.GetClusterName(),
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      "NEW_NAME": self.op.name,
      }
    mn = self.sstore.GetMasterNode()
    return env, [mn], [mn]

  def CheckPrereq(self):
    """Verify that the passed name is a valid one.

    """
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    hostname = utils.HostInfo(self.op.name)
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    new_name = hostname.name
    self.ip = new_ip = hostname.ip
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    old_name = self.sstore.GetClusterName()
    old_ip = self.sstore.GetMasterIP()
    if new_name == old_name and new_ip == old_ip:
      raise errors.OpPrereqError("Neither the name nor the IP address of the"
                                 " cluster has changed")
    if new_ip != old_ip:
      result = utils.RunCmd(["fping", "-q", new_ip])
      if not result.failed:
        raise errors.OpPrereqError("The given cluster IP address (%s) is"
                                   " reachable on the network. Aborting." %
                                   new_ip)

    self.op.name = new_name

  def Exec(self, feedback_fn):
    """Rename the cluster.

    """
    clustername = self.op.name
    ip = self.ip
    ss = self.sstore

    # shutdown the master IP
    master = ss.GetMasterNode()
    if not rpc.call_node_stop_master(master):
      raise errors.OpExecError("Could not disable the master role")

    try:
      # modify the sstore
      ss.SetKey(ss.SS_MASTER_IP, ip)
      ss.SetKey(ss.SS_CLUSTER_NAME, clustername)

      # Distribute updated ss config to all nodes
      myself = self.cfg.GetNodeInfo(master)
      dist_nodes = self.cfg.GetNodeList()
      if myself.name in dist_nodes:
        dist_nodes.remove(myself.name)

      logger.Debug("Copying updated ssconf data to all nodes")
      for keyname in [ss.SS_CLUSTER_NAME, ss.SS_MASTER_IP]:
        fname = ss.KeyToFilename(keyname)
        result = rpc.call_upload_file(dist_nodes, fname)
        for to_node in dist_nodes:
          if not result[to_node]:
            logger.Error("copy of file %s to node %s failed" %
                         (fname, to_node))
    finally:
      if not rpc.call_node_start_master(master):
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        logger.Error("Could not re-enable the master role on the master,"
                     " please restart manually.")
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def _WaitForSync(cfgw, instance, proc, oneshot=False, unlock=False):
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  """Sleep and poll for an instance's disk to sync.

  """
  if not instance.disks:
    return True

  if not oneshot:
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    proc.LogInfo("Waiting for instance %s to sync disks." % instance.name)
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  node = instance.primary_node

  for dev in instance.disks:
    cfgw.SetDiskID(dev, node)

  retries = 0
  while True:
    max_time = 0
    done = True
    cumul_degraded = False
    rstats = rpc.call_blockdev_getmirrorstatus(node, instance.disks)
    if not rstats:
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      proc.LogWarning("Can't get any data from node %s" % node)
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      retries += 1
      if retries >= 10:
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        raise errors.RemoteError("Can't contact node %s for mirror data,"
                                 " aborting." % node)
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      time.sleep(6)
      continue
    retries = 0
    for i in range(len(rstats)):
      mstat = rstats[i]
      if mstat is None:
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        proc.LogWarning("Can't compute data for node %s/%s" %
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                        (node, instance.disks[i].iv_name))
        continue
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      # we ignore the ldisk parameter
      perc_done, est_time, is_degraded, _ = mstat
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      cumul_degraded = cumul_degraded or (is_degraded and perc_done is None)
      if perc_done is not None:
        done = False
        if est_time is not None:
          rem_time = "%d estimated seconds remaining" % est_time
          max_time = est_time
        else:
          rem_time = "no time estimate"
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        proc.LogInfo("- device %s: %5.2f%% done, %s" %
                     (instance.disks[i].iv_name, perc_done, rem_time))
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    if done or oneshot:
      break

    if unlock:
      utils.Unlock('cmd')
    try:
      time.sleep(min(60, max_time))
    finally:
      if unlock:
        utils.Lock('cmd')

  if done:
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    proc.LogInfo("Instance %s's disks are in sync." % instance.name)
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  return not cumul_degraded


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def _CheckDiskConsistency(cfgw, dev, node, on_primary, ldisk=False):
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  """Check that mirrors are not degraded.

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  The ldisk parameter, if True, will change the test from the
  is_degraded attribute (which represents overall non-ok status for
  the device(s)) to the ldisk (representing the local storage status).

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  """
  cfgw.SetDiskID(dev, node)
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  if ldisk:
    idx = 6
  else:
    idx = 5
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  result = True
  if on_primary or dev.AssembleOnSecondary():
    rstats = rpc.call_blockdev_find(node, dev)
    if not rstats:
      logger.ToStderr("Can't get any data from node %s" % node)
      result = False
    else:
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      result = result and (not rstats[idx])
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  if dev.children:
    for child in dev.children:
      result = result and _CheckDiskConsistency(cfgw, child, node, on_primary)

  return result


class LUDiagnoseOS(NoHooksLU):
  """Logical unit for OS diagnose/query.

  """
  _OP_REQP = []

  def CheckPrereq(self):
    """Check prerequisites.

    This always succeeds, since this is a pure query LU.

    """
    return

  def Exec(self, feedback_fn):
    """Compute the list of OSes.

    """
    node_list = self.cfg.GetNodeList()
    node_data = rpc.call_os_diagnose(node_list)
    if node_data == False:
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      raise errors.OpExecError("Can't gather the list of OSes")
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    return node_data


class LURemoveNode(LogicalUnit):
  """Logical unit for removing a node.

  """
  HPATH = "node-remove"
  HTYPE = constants.HTYPE_NODE
  _OP_REQP = ["node_name"]

  def BuildHooksEnv(self):
    """Build hooks env.

    This doesn't run on the target node in the pre phase as a failed
    node would not allows itself to run.

    """
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    env = {
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      "OP_TARGET": self.op.node_name,
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      "NODE_NAME": self.op.node_name,
      }
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    all_nodes = self.cfg.GetNodeList()
    all_nodes.remove(self.op.node_name)
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    return env, all_nodes, all_nodes
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  def CheckPrereq(self):
    """Check prerequisites.

    This checks:
     - the node exists in the configuration
     - it does not have primary or secondary instances
     - it's not the master

    Any errors are signalled by raising errors.OpPrereqError.

    """
    node = self.cfg.GetNodeInfo(self.cfg.ExpandNodeName(self.op.node_name))
    if node is None:
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      raise errors.OpPrereqError, ("Node '%s' is unknown." % self.op.node_name)
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    instance_list = self.cfg.GetInstanceList()

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    masternode = self.sstore.GetMasterNode()
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    if node.name == masternode:
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      raise errors.OpPrereqError("Node is the master node,"
                                 " you need to failover first.")
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    for instance_name in instance_list:
      instance = self.cfg.GetInstanceInfo(instance_name)
      if node.name == instance.primary_node:
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        raise errors.OpPrereqError("Instance %s still running on the node,"
                                   " please remove first." % instance_name)
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      if node.name in instance.secondary_nodes:
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        raise errors.OpPrereqError("Instance %s has node as a secondary,"
                                   " please remove first." % instance_name)
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    self.op.node_name = node.name
    self.node = node

  def Exec(self, feedback_fn):
    """Removes the node from the cluster.

    """
    node = self.node
    logger.Info("stopping the node daemon and removing configs from node %s" %
                node.name)

    rpc.call_node_leave_cluster(node.name)

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    self.ssh.Run(node.name, 'root', "%s stop" % constants.NODE_INITD_SCRIPT)
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    logger.Info("Removing node %s from config" % node.name)

    self.cfg.RemoveNode(node.name)

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    _RemoveHostFromEtcHosts(node.name)

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class LUQueryNodes(NoHooksLU):
  """Logical unit for querying nodes.

  """
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  _OP_REQP = ["output_fields", "names"]
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  def CheckPrereq(self):
    """Check prerequisites.

    This checks that the fields required are valid output fields.

    """
    self.dynamic_fields = frozenset(["dtotal", "dfree",
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                                     "mtotal", "mnode", "mfree",
                                     "bootid"])
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    _CheckOutputFields(static=["name", "pinst_cnt", "sinst_cnt",
                               "pinst_list", "sinst_list",
                               "pip", "sip"],
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                       dynamic=self.dynamic_fields,
                       selected=self.op.output_fields)
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    self.wanted = _GetWantedNodes(self, self.op.names)
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  def Exec(self, feedback_fn):
    """Computes the list of nodes and their attributes.

    """
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    nodenames = self.wanted
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