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#
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#
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# Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Google Inc.
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful, but
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# WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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# General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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# 02110-1301, USA.
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"""Configuration management for Ganeti
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This module provides the interface to the Ganeti cluster configuration.
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The configuration data is stored on every node but is updated on the master
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only. After each update, the master distributes the data to the other nodes.
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Currently, the data storage format is JSON. YAML was slow and consuming too
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much memory.
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"""
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# pylint: disable=R0904
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# R0904: Too many public methods
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import os
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import random
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import logging
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import time
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from ganeti import errors
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from ganeti import locking
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from ganeti import utils
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from ganeti import constants
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from ganeti import rpc
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from ganeti import objects
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from ganeti import serializer
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from ganeti import uidpool
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from ganeti import netutils
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from ganeti import runtime
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_config_lock = locking.SharedLock("ConfigWriter")
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# job id used for resource management at config upgrade time
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_UPGRADE_CONFIG_JID = "jid-cfg-upgrade"
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def _ValidateConfig(data):
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  """Verifies that a configuration objects looks valid.
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  This only verifies the version of the configuration.
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  @raise errors.ConfigurationError: if the version differs from what
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      we expect
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  """
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  if data.version != constants.CONFIG_VERSION:
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    raise errors.ConfigVersionMismatch(constants.CONFIG_VERSION, data.version)
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class TemporaryReservationManager:
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  """A temporary resource reservation manager.
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  This is used to reserve resources in a job, before using them, making sure
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  other jobs cannot get them in the meantime.
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  """
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  def __init__(self):
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    self._ec_reserved = {}
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  def Reserved(self, resource):
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    for holder_reserved in self._ec_reserved.values():
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      if resource in holder_reserved:
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        return True
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    return False
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  def Reserve(self, ec_id, resource):
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    if self.Reserved(resource):
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      raise errors.ReservationError("Duplicate reservation for resource '%s'"
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                                    % str(resource))
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    if ec_id not in self._ec_reserved:
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      self._ec_reserved[ec_id] = set([resource])
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    else:
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      self._ec_reserved[ec_id].add(resource)
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  def DropECReservations(self, ec_id):
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    if ec_id in self._ec_reserved:
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      del self._ec_reserved[ec_id]
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  def GetReserved(self):
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    all_reserved = set()
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    for holder_reserved in self._ec_reserved.values():
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      all_reserved.update(holder_reserved)
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    return all_reserved
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  def Generate(self, existing, generate_one_fn, ec_id):
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    """Generate a new resource of this type
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    """
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    assert callable(generate_one_fn)
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    all_elems = self.GetReserved()
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    all_elems.update(existing)
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    retries = 64
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    while retries > 0:
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      new_resource = generate_one_fn()
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      if new_resource is not None and new_resource not in all_elems:
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        break
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    else:
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      raise errors.ConfigurationError("Not able generate new resource"
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                                      " (last tried: %s)" % new_resource)
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    self.Reserve(ec_id, new_resource)
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    return new_resource
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127

    
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def _MatchNameComponentIgnoreCase(short_name, names):
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  """Wrapper around L{utils.text.MatchNameComponent}.
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131
  """
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  return utils.MatchNameComponent(short_name, names, case_sensitive=False)
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class ConfigWriter:
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  """The interface to the cluster configuration.
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  @ivar _temporary_lvs: reservation manager for temporary LVs
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  @ivar _all_rms: a list of all temporary reservation managers
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  """
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  def __init__(self, cfg_file=None, offline=False, _getents=runtime.GetEnts,
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               accept_foreign=False):
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    self.write_count = 0
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    self._lock = _config_lock
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    self._config_data = None
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    self._offline = offline
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    if cfg_file is None:
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      self._cfg_file = constants.CLUSTER_CONF_FILE
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    else:
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      self._cfg_file = cfg_file
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    self._getents = _getents
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    self._temporary_ids = TemporaryReservationManager()
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    self._temporary_drbds = {}
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    self._temporary_macs = TemporaryReservationManager()
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    self._temporary_secrets = TemporaryReservationManager()
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    self._temporary_lvs = TemporaryReservationManager()
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    self._all_rms = [self._temporary_ids, self._temporary_macs,
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                     self._temporary_secrets, self._temporary_lvs]
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    # Note: in order to prevent errors when resolving our name in
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    # _DistributeConfig, we compute it here once and reuse it; it's
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    # better to raise an error before starting to modify the config
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    # file than after it was modified
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    self._my_hostname = netutils.Hostname.GetSysName()
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    self._last_cluster_serial = -1
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    self._cfg_id = None
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    self._OpenConfig(accept_foreign)
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  # this method needs to be static, so that we can call it on the class
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  @staticmethod
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  def IsCluster():
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    """Check if the cluster is configured.
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174
    """
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    return os.path.exists(constants.CLUSTER_CONF_FILE)
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177
  def _GenerateOneMAC(self):
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    """Generate one mac address
179

180
    """
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    prefix = self._config_data.cluster.mac_prefix
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    byte1 = random.randrange(0, 256)
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    byte2 = random.randrange(0, 256)
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    byte3 = random.randrange(0, 256)
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    mac = "%s:%02x:%02x:%02x" % (prefix, byte1, byte2, byte3)
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    return mac
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  @locking.ssynchronized(_config_lock, shared=1)
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  def GetNdParams(self, node):
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    """Get the node params populated with cluster defaults.
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    @type node: L{objects.Node}
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    @param node: The node we want to know the params for
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    @return: A dict with the filled in node params
195

196
    """
197
    nodegroup = self._UnlockedGetNodeGroup(node.group)
198
    return self._config_data.cluster.FillND(node, nodegroup)
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200
  @locking.ssynchronized(_config_lock, shared=1)
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  def GenerateMAC(self, ec_id):
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    """Generate a MAC for an instance.
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204
    This should check the current instances for duplicates.
205

206
    """
207
    existing = self._AllMACs()
208
    return self._temporary_ids.Generate(existing, self._GenerateOneMAC, ec_id)
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210
  @locking.ssynchronized(_config_lock, shared=1)
211
  def ReserveMAC(self, mac, ec_id):
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    """Reserve a MAC for an instance.
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    This only checks instances managed by this cluster, it does not
215
    check for potential collisions elsewhere.
216

217
    """
218
    all_macs = self._AllMACs()
219
    if mac in all_macs:
220
      raise errors.ReservationError("mac already in use")
221
    else:
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      self._temporary_macs.Reserve(ec_id, mac)
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224
  @locking.ssynchronized(_config_lock, shared=1)
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  def ReserveLV(self, lv_name, ec_id):
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    """Reserve an VG/LV pair for an instance.
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    @type lv_name: string
229
    @param lv_name: the logical volume name to reserve
230

231
    """
232
    all_lvs = self._AllLVs()
233
    if lv_name in all_lvs:
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      raise errors.ReservationError("LV already in use")
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    else:
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      self._temporary_lvs.Reserve(ec_id, lv_name)
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  @locking.ssynchronized(_config_lock, shared=1)
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  def GenerateDRBDSecret(self, ec_id):
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    """Generate a DRBD secret.
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    This checks the current disks for duplicates.
243

244
    """
245
    return self._temporary_secrets.Generate(self._AllDRBDSecrets(),
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                                            utils.GenerateSecret,
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                                            ec_id)
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249
  def _AllLVs(self):
250
    """Compute the list of all LVs.
251

252
    """
253
    lvnames = set()
254
    for instance in self._config_data.instances.values():
255
      node_data = instance.MapLVsByNode()
256
      for lv_list in node_data.values():
257
        lvnames.update(lv_list)
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    return lvnames
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260
  def _AllIDs(self, include_temporary):
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    """Compute the list of all UUIDs and names we have.
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263
    @type include_temporary: boolean
264
    @param include_temporary: whether to include the _temporary_ids set
265
    @rtype: set
266
    @return: a set of IDs
267

268
    """
269
    existing = set()
270
    if include_temporary:
271
      existing.update(self._temporary_ids.GetReserved())
272
    existing.update(self._AllLVs())
273
    existing.update(self._config_data.instances.keys())
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    existing.update(self._config_data.nodes.keys())
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    existing.update([i.uuid for i in self._AllUUIDObjects() if i.uuid])
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    return existing
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278
  def _GenerateUniqueID(self, ec_id):
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    """Generate an unique UUID.
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281
    This checks the current node, instances and disk names for
282
    duplicates.
283

284
    @rtype: string
285
    @return: the unique id
286

287
    """
288
    existing = self._AllIDs(include_temporary=False)
289
    return self._temporary_ids.Generate(existing, utils.NewUUID, ec_id)
290

    
291
  @locking.ssynchronized(_config_lock, shared=1)
292
  def GenerateUniqueID(self, ec_id):
293
    """Generate an unique ID.
294

295
    This is just a wrapper over the unlocked version.
296

297
    @type ec_id: string
298
    @param ec_id: unique id for the job to reserve the id to
299

300
    """
301
    return self._GenerateUniqueID(ec_id)
302

    
303
  def _AllMACs(self):
304
    """Return all MACs present in the config.
305

306
    @rtype: list
307
    @return: the list of all MACs
308

309
    """
310
    result = []
311
    for instance in self._config_data.instances.values():
312
      for nic in instance.nics:
313
        result.append(nic.mac)
314

    
315
    return result
316

    
317
  def _AllDRBDSecrets(self):
318
    """Return all DRBD secrets present in the config.
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320
    @rtype: list
321
    @return: the list of all DRBD secrets
322

323
    """
324
    def helper(disk, result):
325
      """Recursively gather secrets from this disk."""
326
      if disk.dev_type == constants.DT_DRBD8:
327
        result.append(disk.logical_id[5])
328
      if disk.children:
329
        for child in disk.children:
330
          helper(child, result)
331

    
332
    result = []
333
    for instance in self._config_data.instances.values():
334
      for disk in instance.disks:
335
        helper(disk, result)
336

    
337
    return result
338

    
339
  def _CheckDiskIDs(self, disk, l_ids, p_ids):
340
    """Compute duplicate disk IDs
341

342
    @type disk: L{objects.Disk}
343
    @param disk: the disk at which to start searching
344
    @type l_ids: list
345
    @param l_ids: list of current logical ids
346
    @type p_ids: list
347
    @param p_ids: list of current physical ids
348
    @rtype: list
349
    @return: a list of error messages
350

351
    """
352
    result = []
353
    if disk.logical_id is not None:
354
      if disk.logical_id in l_ids:
355
        result.append("duplicate logical id %s" % str(disk.logical_id))
356
      else:
357
        l_ids.append(disk.logical_id)
358
    if disk.physical_id is not None:
359
      if disk.physical_id in p_ids:
360
        result.append("duplicate physical id %s" % str(disk.physical_id))
361
      else:
362
        p_ids.append(disk.physical_id)
363

    
364
    if disk.children:
365
      for child in disk.children:
366
        result.extend(self._CheckDiskIDs(child, l_ids, p_ids))
367
    return result
368

    
369
  def _UnlockedVerifyConfig(self):
370
    """Verify function.
371

372
    @rtype: list
373
    @return: a list of error messages; a non-empty list signifies
374
        configuration errors
375

376
    """
377
    # pylint: disable=R0914
378
    result = []
379
    seen_macs = []
380
    ports = {}
381
    data = self._config_data
382
    cluster = data.cluster
383
    seen_lids = []
384
    seen_pids = []
385

    
386
    # global cluster checks
387
    if not cluster.enabled_hypervisors:
388
      result.append("enabled hypervisors list doesn't have any entries")
389
    invalid_hvs = set(cluster.enabled_hypervisors) - constants.HYPER_TYPES
390
    if invalid_hvs:
391
      result.append("enabled hypervisors contains invalid entries: %s" %
392
                    invalid_hvs)
393
    missing_hvp = (set(cluster.enabled_hypervisors) -
394
                   set(cluster.hvparams.keys()))
395
    if missing_hvp:
396
      result.append("hypervisor parameters missing for the enabled"
397
                    " hypervisor(s) %s" % utils.CommaJoin(missing_hvp))
398

    
399
    if cluster.master_node not in data.nodes:
400
      result.append("cluster has invalid primary node '%s'" %
401
                    cluster.master_node)
402

    
403
    def _helper(owner, attr, value, template):
404
      try:
405
        utils.ForceDictType(value, template)
406
      except errors.GenericError, err:
407
        result.append("%s has invalid %s: %s" % (owner, attr, err))
408

    
409
    def _helper_nic(owner, params):
410
      try:
411
        objects.NIC.CheckParameterSyntax(params)
412
      except errors.ConfigurationError, err:
413
        result.append("%s has invalid nicparams: %s" % (owner, err))
414

    
415
    # check cluster parameters
416
    _helper("cluster", "beparams", cluster.SimpleFillBE({}),
417
            constants.BES_PARAMETER_TYPES)
418
    _helper("cluster", "nicparams", cluster.SimpleFillNIC({}),
419
            constants.NICS_PARAMETER_TYPES)
420
    _helper_nic("cluster", cluster.SimpleFillNIC({}))
421
    _helper("cluster", "ndparams", cluster.SimpleFillND({}),
422
            constants.NDS_PARAMETER_TYPES)
423

    
424
    # per-instance checks
425
    for instance_name in data.instances:
426
      instance = data.instances[instance_name]
427
      if instance.name != instance_name:
428
        result.append("instance '%s' is indexed by wrong name '%s'" %
429
                      (instance.name, instance_name))
430
      if instance.primary_node not in data.nodes:
431
        result.append("instance '%s' has invalid primary node '%s'" %
432
                      (instance_name, instance.primary_node))
433
      for snode in instance.secondary_nodes:
434
        if snode not in data.nodes:
435
          result.append("instance '%s' has invalid secondary node '%s'" %
436
                        (instance_name, snode))
437
      for idx, nic in enumerate(instance.nics):
438
        if nic.mac in seen_macs:
439
          result.append("instance '%s' has NIC %d mac %s duplicate" %
440
                        (instance_name, idx, nic.mac))
441
        else:
442
          seen_macs.append(nic.mac)
443
        if nic.nicparams:
444
          filled = cluster.SimpleFillNIC(nic.nicparams)
445
          owner = "instance %s nic %d" % (instance.name, idx)
446
          _helper(owner, "nicparams",
447
                  filled, constants.NICS_PARAMETER_TYPES)
448
          _helper_nic(owner, filled)
449

    
450
      # parameter checks
451
      if instance.beparams:
452
        _helper("instance %s" % instance.name, "beparams",
453
                cluster.FillBE(instance), constants.BES_PARAMETER_TYPES)
454

    
455
      # gather the drbd ports for duplicate checks
456
      for dsk in instance.disks:
457
        if dsk.dev_type in constants.LDS_DRBD:
458
          tcp_port = dsk.logical_id[2]
459
          if tcp_port not in ports:
460
            ports[tcp_port] = []
461
          ports[tcp_port].append((instance.name, "drbd disk %s" % dsk.iv_name))
462
      # gather network port reservation
463
      net_port = getattr(instance, "network_port", None)
464
      if net_port is not None:
465
        if net_port not in ports:
466
          ports[net_port] = []
467
        ports[net_port].append((instance.name, "network port"))
468

    
469
      # instance disk verify
470
      for idx, disk in enumerate(instance.disks):
471
        result.extend(["instance '%s' disk %d error: %s" %
472
                       (instance.name, idx, msg) for msg in disk.Verify()])
473
        result.extend(self._CheckDiskIDs(disk, seen_lids, seen_pids))
474

    
475
    # cluster-wide pool of free ports
476
    for free_port in cluster.tcpudp_port_pool:
477
      if free_port not in ports:
478
        ports[free_port] = []
479
      ports[free_port].append(("cluster", "port marked as free"))
480

    
481
    # compute tcp/udp duplicate ports
482
    keys = ports.keys()
483
    keys.sort()
484
    for pnum in keys:
485
      pdata = ports[pnum]
486
      if len(pdata) > 1:
487
        txt = utils.CommaJoin(["%s/%s" % val for val in pdata])
488
        result.append("tcp/udp port %s has duplicates: %s" % (pnum, txt))
489

    
490
    # highest used tcp port check
491
    if keys:
492
      if keys[-1] > cluster.highest_used_port:
493
        result.append("Highest used port mismatch, saved %s, computed %s" %
494
                      (cluster.highest_used_port, keys[-1]))
495

    
496
    if not data.nodes[cluster.master_node].master_candidate:
497
      result.append("Master node is not a master candidate")
498

    
499
    # master candidate checks
500
    mc_now, mc_max, _ = self._UnlockedGetMasterCandidateStats()
501
    if mc_now < mc_max:
502
      result.append("Not enough master candidates: actual %d, target %d" %
503
                    (mc_now, mc_max))
504

    
505
    # node checks
506
    for node_name, node in data.nodes.items():
507
      if node.name != node_name:
508
        result.append("Node '%s' is indexed by wrong name '%s'" %
509
                      (node.name, node_name))
510
      if [node.master_candidate, node.drained, node.offline].count(True) > 1:
511
        result.append("Node %s state is invalid: master_candidate=%s,"
512
                      " drain=%s, offline=%s" %
513
                      (node.name, node.master_candidate, node.drained,
514
                       node.offline))
515
      if node.group not in data.nodegroups:
516
        result.append("Node '%s' has invalid group '%s'" %
517
                      (node.name, node.group))
518
      else:
519
        _helper("node %s" % node.name, "ndparams",
520
                cluster.FillND(node, data.nodegroups[node.group]),
521
                constants.NDS_PARAMETER_TYPES)
522

    
523
    # nodegroups checks
524
    nodegroups_names = set()
525
    for nodegroup_uuid in data.nodegroups:
526
      nodegroup = data.nodegroups[nodegroup_uuid]
527
      if nodegroup.uuid != nodegroup_uuid:
528
        result.append("node group '%s' (uuid: '%s') indexed by wrong uuid '%s'"
529
                      % (nodegroup.name, nodegroup.uuid, nodegroup_uuid))
530
      if utils.UUID_RE.match(nodegroup.name.lower()):
531
        result.append("node group '%s' (uuid: '%s') has uuid-like name" %
532
                      (nodegroup.name, nodegroup.uuid))
533
      if nodegroup.name in nodegroups_names:
534
        result.append("duplicate node group name '%s'" % nodegroup.name)
535
      else:
536
        nodegroups_names.add(nodegroup.name)
537
      if nodegroup.ndparams:
538
        _helper("group %s" % nodegroup.name, "ndparams",
539
                cluster.SimpleFillND(nodegroup.ndparams),
540
                constants.NDS_PARAMETER_TYPES)
541

    
542
    # drbd minors check
543
    _, duplicates = self._UnlockedComputeDRBDMap()
544
    for node, minor, instance_a, instance_b in duplicates:
545
      result.append("DRBD minor %d on node %s is assigned twice to instances"
546
                    " %s and %s" % (minor, node, instance_a, instance_b))
547

    
548
    # IP checks
549
    default_nicparams = cluster.nicparams[constants.PP_DEFAULT]
550
    ips = {}
551

    
552
    def _AddIpAddress(ip, name):
553
      ips.setdefault(ip, []).append(name)
554

    
555
    _AddIpAddress(cluster.master_ip, "cluster_ip")
556

    
557
    for node in data.nodes.values():
558
      _AddIpAddress(node.primary_ip, "node:%s/primary" % node.name)
559
      if node.secondary_ip != node.primary_ip:
560
        _AddIpAddress(node.secondary_ip, "node:%s/secondary" % node.name)
561

    
562
    for instance in data.instances.values():
563
      for idx, nic in enumerate(instance.nics):
564
        if nic.ip is None:
565
          continue
566

    
567
        nicparams = objects.FillDict(default_nicparams, nic.nicparams)
568
        nic_mode = nicparams[constants.NIC_MODE]
569
        nic_link = nicparams[constants.NIC_LINK]
570

    
571
        if nic_mode == constants.NIC_MODE_BRIDGED:
572
          link = "bridge:%s" % nic_link
573
        elif nic_mode == constants.NIC_MODE_ROUTED:
574
          link = "route:%s" % nic_link
575
        else:
576
          raise errors.ProgrammerError("NIC mode '%s' not handled" % nic_mode)
577

    
578
        _AddIpAddress("%s/%s" % (link, nic.ip),
579
                      "instance:%s/nic:%d" % (instance.name, idx))
580

    
581
    for ip, owners in ips.items():
582
      if len(owners) > 1:
583
        result.append("IP address %s is used by multiple owners: %s" %
584
                      (ip, utils.CommaJoin(owners)))
585

    
586
    return result
587

    
588
  @locking.ssynchronized(_config_lock, shared=1)
589
  def VerifyConfig(self):
590
    """Verify function.
591

592
    This is just a wrapper over L{_UnlockedVerifyConfig}.
593

594
    @rtype: list
595
    @return: a list of error messages; a non-empty list signifies
596
        configuration errors
597

598
    """
599
    return self._UnlockedVerifyConfig()
600

    
601
  def _UnlockedSetDiskID(self, disk, node_name):
602
    """Convert the unique ID to the ID needed on the target nodes.
603

604
    This is used only for drbd, which needs ip/port configuration.
605

606
    The routine descends down and updates its children also, because
607
    this helps when the only the top device is passed to the remote
608
    node.
609

610
    This function is for internal use, when the config lock is already held.
611

612
    """
613
    if disk.children:
614
      for child in disk.children:
615
        self._UnlockedSetDiskID(child, node_name)
616

    
617
    if disk.logical_id is None and disk.physical_id is not None:
618
      return
619
    if disk.dev_type == constants.LD_DRBD8:
620
      pnode, snode, port, pminor, sminor, secret = disk.logical_id
621
      if node_name not in (pnode, snode):
622
        raise errors.ConfigurationError("DRBD device not knowing node %s" %
623
                                        node_name)
624
      pnode_info = self._UnlockedGetNodeInfo(pnode)
625
      snode_info = self._UnlockedGetNodeInfo(snode)
626
      if pnode_info is None or snode_info is None:
627
        raise errors.ConfigurationError("Can't find primary or secondary node"
628
                                        " for %s" % str(disk))
629
      p_data = (pnode_info.secondary_ip, port)
630
      s_data = (snode_info.secondary_ip, port)
631
      if pnode == node_name:
632
        disk.physical_id = p_data + s_data + (pminor, secret)
633
      else: # it must be secondary, we tested above
634
        disk.physical_id = s_data + p_data + (sminor, secret)
635
    else:
636
      disk.physical_id = disk.logical_id
637
    return
638

    
639
  @locking.ssynchronized(_config_lock)
640
  def SetDiskID(self, disk, node_name):
641
    """Convert the unique ID to the ID needed on the target nodes.
642

643
    This is used only for drbd, which needs ip/port configuration.
644

645
    The routine descends down and updates its children also, because
646
    this helps when the only the top device is passed to the remote
647
    node.
648

649
    """
650
    return self._UnlockedSetDiskID(disk, node_name)
651

    
652
  @locking.ssynchronized(_config_lock)
653
  def AddTcpUdpPort(self, port):
654
    """Adds a new port to the available port pool.
655

656
    """
657
    if not isinstance(port, int):
658
      raise errors.ProgrammerError("Invalid type passed for port")
659

    
660
    self._config_data.cluster.tcpudp_port_pool.add(port)
661
    self._WriteConfig()
662

    
663
  @locking.ssynchronized(_config_lock, shared=1)
664
  def GetPortList(self):
665
    """Returns a copy of the current port list.
666

667
    """
668
    return self._config_data.cluster.tcpudp_port_pool.copy()
669

    
670
  @locking.ssynchronized(_config_lock)
671
  def AllocatePort(self):
672
    """Allocate a port.
673

674
    The port will be taken from the available port pool or from the
675
    default port range (and in this case we increase
676
    highest_used_port).
677

678
    """
679
    # If there are TCP/IP ports configured, we use them first.
680
    if self._config_data.cluster.tcpudp_port_pool:
681
      port = self._config_data.cluster.tcpudp_port_pool.pop()
682
    else:
683
      port = self._config_data.cluster.highest_used_port + 1
684
      if port >= constants.LAST_DRBD_PORT:
685
        raise errors.ConfigurationError("The highest used port is greater"
686
                                        " than %s. Aborting." %
687
                                        constants.LAST_DRBD_PORT)
688
      self._config_data.cluster.highest_used_port = port
689

    
690
    self._WriteConfig()
691
    return port
692

    
693
  def _UnlockedComputeDRBDMap(self):
694
    """Compute the used DRBD minor/nodes.
695

696
    @rtype: (dict, list)
697
    @return: dictionary of node_name: dict of minor: instance_name;
698
        the returned dict will have all the nodes in it (even if with
699
        an empty list), and a list of duplicates; if the duplicates
700
        list is not empty, the configuration is corrupted and its caller
701
        should raise an exception
702

703
    """
704
    def _AppendUsedPorts(instance_name, disk, used):
705
      duplicates = []
706
      if disk.dev_type == constants.LD_DRBD8 and len(disk.logical_id) >= 5:
707
        node_a, node_b, _, minor_a, minor_b = disk.logical_id[:5]
708
        for node, port in ((node_a, minor_a), (node_b, minor_b)):
709
          assert node in used, ("Node '%s' of instance '%s' not found"
710
                                " in node list" % (node, instance_name))
711
          if port in used[node]:
712
            duplicates.append((node, port, instance_name, used[node][port]))
713
          else:
714
            used[node][port] = instance_name
715
      if disk.children:
716
        for child in disk.children:
717
          duplicates.extend(_AppendUsedPorts(instance_name, child, used))
718
      return duplicates
719

    
720
    duplicates = []
721
    my_dict = dict((node, {}) for node in self._config_data.nodes)
722
    for instance in self._config_data.instances.itervalues():
723
      for disk in instance.disks:
724
        duplicates.extend(_AppendUsedPorts(instance.name, disk, my_dict))
725
    for (node, minor), instance in self._temporary_drbds.iteritems():
726
      if minor in my_dict[node] and my_dict[node][minor] != instance:
727
        duplicates.append((node, minor, instance, my_dict[node][minor]))
728
      else:
729
        my_dict[node][minor] = instance
730
    return my_dict, duplicates
731

    
732
  @locking.ssynchronized(_config_lock)
733
  def ComputeDRBDMap(self):
734
    """Compute the used DRBD minor/nodes.
735

736
    This is just a wrapper over L{_UnlockedComputeDRBDMap}.
737

738
    @return: dictionary of node_name: dict of minor: instance_name;
739
        the returned dict will have all the nodes in it (even if with
740
        an empty list).
741

742
    """
743
    d_map, duplicates = self._UnlockedComputeDRBDMap()
744
    if duplicates:
745
      raise errors.ConfigurationError("Duplicate DRBD ports detected: %s" %
746
                                      str(duplicates))
747
    return d_map
748

    
749
  @locking.ssynchronized(_config_lock)
750
  def AllocateDRBDMinor(self, nodes, instance):
751
    """Allocate a drbd minor.
752

753
    The free minor will be automatically computed from the existing
754
    devices. A node can be given multiple times in order to allocate
755
    multiple minors. The result is the list of minors, in the same
756
    order as the passed nodes.
757

758
    @type instance: string
759
    @param instance: the instance for which we allocate minors
760

761
    """
762
    assert isinstance(instance, basestring), \
763
           "Invalid argument '%s' passed to AllocateDRBDMinor" % instance
764

    
765
    d_map, duplicates = self._UnlockedComputeDRBDMap()
766
    if duplicates:
767
      raise errors.ConfigurationError("Duplicate DRBD ports detected: %s" %
768
                                      str(duplicates))
769
    result = []
770
    for nname in nodes:
771
      ndata = d_map[nname]
772
      if not ndata:
773
        # no minors used, we can start at 0
774
        result.append(0)
775
        ndata[0] = instance
776
        self._temporary_drbds[(nname, 0)] = instance
777
        continue
778
      keys = ndata.keys()
779
      keys.sort()
780
      ffree = utils.FirstFree(keys)
781
      if ffree is None:
782
        # return the next minor
783
        # TODO: implement high-limit check
784
        minor = keys[-1] + 1
785
      else:
786
        minor = ffree
787
      # double-check minor against current instances
788
      assert minor not in d_map[nname], \
789
             ("Attempt to reuse allocated DRBD minor %d on node %s,"
790
              " already allocated to instance %s" %
791
              (minor, nname, d_map[nname][minor]))
792
      ndata[minor] = instance
793
      # double-check minor against reservation
794
      r_key = (nname, minor)
795
      assert r_key not in self._temporary_drbds, \
796
             ("Attempt to reuse reserved DRBD minor %d on node %s,"
797
              " reserved for instance %s" %
798
              (minor, nname, self._temporary_drbds[r_key]))
799
      self._temporary_drbds[r_key] = instance
800
      result.append(minor)
801
    logging.debug("Request to allocate drbd minors, input: %s, returning %s",
802
                  nodes, result)
803
    return result
804

    
805
  def _UnlockedReleaseDRBDMinors(self, instance):
806
    """Release temporary drbd minors allocated for a given instance.
807

808
    @type instance: string
809
    @param instance: the instance for which temporary minors should be
810
                     released
811

812
    """
813
    assert isinstance(instance, basestring), \
814
           "Invalid argument passed to ReleaseDRBDMinors"
815
    for key, name in self._temporary_drbds.items():
816
      if name == instance:
817
        del self._temporary_drbds[key]
818

    
819
  @locking.ssynchronized(_config_lock)
820
  def ReleaseDRBDMinors(self, instance):
821
    """Release temporary drbd minors allocated for a given instance.
822

823
    This should be called on the error paths, on the success paths
824
    it's automatically called by the ConfigWriter add and update
825
    functions.
826

827
    This function is just a wrapper over L{_UnlockedReleaseDRBDMinors}.
828

829
    @type instance: string
830
    @param instance: the instance for which temporary minors should be
831
                     released
832

833
    """
834
    self._UnlockedReleaseDRBDMinors(instance)
835

    
836
  @locking.ssynchronized(_config_lock, shared=1)
837
  def GetConfigVersion(self):
838
    """Get the configuration version.
839

840
    @return: Config version
841

842
    """
843
    return self._config_data.version
844

    
845
  @locking.ssynchronized(_config_lock, shared=1)
846
  def GetClusterName(self):
847
    """Get cluster name.
848

849
    @return: Cluster name
850

851
    """
852
    return self._config_data.cluster.cluster_name
853

    
854
  @locking.ssynchronized(_config_lock, shared=1)
855
  def GetMasterNode(self):
856
    """Get the hostname of the master node for this cluster.
857

858
    @return: Master hostname
859

860
    """
861
    return self._config_data.cluster.master_node
862

    
863
  @locking.ssynchronized(_config_lock, shared=1)
864
  def GetMasterIP(self):
865
    """Get the IP of the master node for this cluster.
866

867
    @return: Master IP
868

869
    """
870
    return self._config_data.cluster.master_ip
871

    
872
  @locking.ssynchronized(_config_lock, shared=1)
873
  def GetMasterNetdev(self):
874
    """Get the master network device for this cluster.
875

876
    """
877
    return self._config_data.cluster.master_netdev
878

    
879
  @locking.ssynchronized(_config_lock, shared=1)
880
  def GetFileStorageDir(self):
881
    """Get the file storage dir for this cluster.
882

883
    """
884
    return self._config_data.cluster.file_storage_dir
885

    
886
  @locking.ssynchronized(_config_lock, shared=1)
887
  def GetSharedFileStorageDir(self):
888
    """Get the shared file storage dir for this cluster.
889

890
    """
891
    return self._config_data.cluster.shared_file_storage_dir
892

    
893
  @locking.ssynchronized(_config_lock, shared=1)
894
  def GetHypervisorType(self):
895
    """Get the hypervisor type for this cluster.
896

897
    """
898
    return self._config_data.cluster.enabled_hypervisors[0]
899

    
900
  @locking.ssynchronized(_config_lock, shared=1)
901
  def GetHostKey(self):
902
    """Return the rsa hostkey from the config.
903

904
    @rtype: string
905
    @return: the rsa hostkey
906

907
    """
908
    return self._config_data.cluster.rsahostkeypub
909

    
910
  @locking.ssynchronized(_config_lock, shared=1)
911
  def GetDefaultIAllocator(self):
912
    """Get the default instance allocator for this cluster.
913

914
    """
915
    return self._config_data.cluster.default_iallocator
916

    
917
  @locking.ssynchronized(_config_lock, shared=1)
918
  def GetPrimaryIPFamily(self):
919
    """Get cluster primary ip family.
920

921
    @return: primary ip family
922

923
    """
924
    return self._config_data.cluster.primary_ip_family
925

    
926
  @locking.ssynchronized(_config_lock)
927
  def AddNodeGroup(self, group, ec_id, check_uuid=True):
928
    """Add a node group to the configuration.
929

930
    This method calls group.UpgradeConfig() to fill any missing attributes
931
    according to their default values.
932

933
    @type group: L{objects.NodeGroup}
934
    @param group: the NodeGroup object to add
935
    @type ec_id: string
936
    @param ec_id: unique id for the job to use when creating a missing UUID
937
    @type check_uuid: bool
938
    @param check_uuid: add an UUID to the group if it doesn't have one or, if
939
                       it does, ensure that it does not exist in the
940
                       configuration already
941

942
    """
943
    self._UnlockedAddNodeGroup(group, ec_id, check_uuid)
944
    self._WriteConfig()
945

    
946
  def _UnlockedAddNodeGroup(self, group, ec_id, check_uuid):
947
    """Add a node group to the configuration.
948

949
    """
950
    logging.info("Adding node group %s to configuration", group.name)
951

    
952
    # Some code might need to add a node group with a pre-populated UUID
953
    # generated with ConfigWriter.GenerateUniqueID(). We allow them to bypass
954
    # the "does this UUID" exist already check.
955
    if check_uuid:
956
      self._EnsureUUID(group, ec_id)
957

    
958
    try:
959
      existing_uuid = self._UnlockedLookupNodeGroup(group.name)
960
    except errors.OpPrereqError:
961
      pass
962
    else:
963
      raise errors.OpPrereqError("Desired group name '%s' already exists as a"
964
                                 " node group (UUID: %s)" %
965
                                 (group.name, existing_uuid),
966
                                 errors.ECODE_EXISTS)
967

    
968
    group.serial_no = 1
969
    group.ctime = group.mtime = time.time()
970
    group.UpgradeConfig()
971

    
972
    self._config_data.nodegroups[group.uuid] = group
973
    self._config_data.cluster.serial_no += 1
974

    
975
  @locking.ssynchronized(_config_lock)
976
  def RemoveNodeGroup(self, group_uuid):
977
    """Remove a node group from the configuration.
978

979
    @type group_uuid: string
980
    @param group_uuid: the UUID of the node group to remove
981

982
    """
983
    logging.info("Removing node group %s from configuration", group_uuid)
984

    
985
    if group_uuid not in self._config_data.nodegroups:
986
      raise errors.ConfigurationError("Unknown node group '%s'" % group_uuid)
987

    
988
    assert len(self._config_data.nodegroups) != 1, \
989
            "Group '%s' is the only group, cannot be removed" % group_uuid
990

    
991
    del self._config_data.nodegroups[group_uuid]
992
    self._config_data.cluster.serial_no += 1
993
    self._WriteConfig()
994

    
995
  def _UnlockedLookupNodeGroup(self, target):
996
    """Lookup a node group's UUID.
997

998
    @type target: string or None
999
    @param target: group name or UUID or None to look for the default
1000
    @rtype: string
1001
    @return: nodegroup UUID
1002
    @raises errors.OpPrereqError: when the target group cannot be found
1003

1004
    """
1005
    if target is None:
1006
      if len(self._config_data.nodegroups) != 1:
1007
        raise errors.OpPrereqError("More than one node group exists. Target"
1008
                                   " group must be specified explicitely.")
1009
      else:
1010
        return self._config_data.nodegroups.keys()[0]
1011
    if target in self._config_data.nodegroups:
1012
      return target
1013
    for nodegroup in self._config_data.nodegroups.values():
1014
      if nodegroup.name == target:
1015
        return nodegroup.uuid
1016
    raise errors.OpPrereqError("Node group '%s' not found" % target,
1017
                               errors.ECODE_NOENT)
1018

    
1019
  @locking.ssynchronized(_config_lock, shared=1)
1020
  def LookupNodeGroup(self, target):
1021
    """Lookup a node group's UUID.
1022

1023
    This function is just a wrapper over L{_UnlockedLookupNodeGroup}.
1024

1025
    @type target: string or None
1026
    @param target: group name or UUID or None to look for the default
1027
    @rtype: string
1028
    @return: nodegroup UUID
1029

1030
    """
1031
    return self._UnlockedLookupNodeGroup(target)
1032

    
1033
  def _UnlockedGetNodeGroup(self, uuid):
1034
    """Lookup a node group.
1035

1036
    @type uuid: string
1037
    @param uuid: group UUID
1038
    @rtype: L{objects.NodeGroup} or None
1039
    @return: nodegroup object, or None if not found
1040

1041
    """
1042
    if uuid not in self._config_data.nodegroups:
1043
      return None
1044

    
1045
    return self._config_data.nodegroups[uuid]
1046

    
1047
  @locking.ssynchronized(_config_lock, shared=1)
1048
  def GetNodeGroup(self, uuid):
1049
    """Lookup a node group.
1050

1051
    @type uuid: string
1052
    @param uuid: group UUID
1053
    @rtype: L{objects.NodeGroup} or None
1054
    @return: nodegroup object, or None if not found
1055

1056
    """
1057
    return self._UnlockedGetNodeGroup(uuid)
1058

    
1059
  @locking.ssynchronized(_config_lock, shared=1)
1060
  def GetAllNodeGroupsInfo(self):
1061
    """Get the configuration of all node groups.
1062

1063
    """
1064
    return dict(self._config_data.nodegroups)
1065

    
1066
  @locking.ssynchronized(_config_lock, shared=1)
1067
  def GetNodeGroupList(self):
1068
    """Get a list of node groups.
1069

1070
    """
1071
    return self._config_data.nodegroups.keys()
1072

    
1073
  @locking.ssynchronized(_config_lock, shared=1)
1074
  def GetNodeGroupMembersByNodes(self, nodes):
1075
    """Get nodes which are member in the same nodegroups as the given nodes.
1076

1077
    """
1078
    ngfn = lambda node_name: self._UnlockedGetNodeInfo(node_name).group
1079
    return frozenset(member_name
1080
                     for node_name in nodes
1081
                     for member_name in
1082
                       self._UnlockedGetNodeGroup(ngfn(node_name)).members)
1083

    
1084
  @locking.ssynchronized(_config_lock)
1085
  def AddInstance(self, instance, ec_id):
1086
    """Add an instance to the config.
1087

1088
    This should be used after creating a new instance.
1089

1090
    @type instance: L{objects.Instance}
1091
    @param instance: the instance object
1092

1093
    """
1094
    if not isinstance(instance, objects.Instance):
1095
      raise errors.ProgrammerError("Invalid type passed to AddInstance")
1096

    
1097
    if instance.disk_template != constants.DT_DISKLESS:
1098
      all_lvs = instance.MapLVsByNode()
1099
      logging.info("Instance '%s' DISK_LAYOUT: %s", instance.name, all_lvs)
1100

    
1101
    all_macs = self._AllMACs()
1102
    for nic in instance.nics:
1103
      if nic.mac in all_macs:
1104
        raise errors.ConfigurationError("Cannot add instance %s:"
1105
                                        " MAC address '%s' already in use." %
1106
                                        (instance.name, nic.mac))
1107

    
1108
    self._EnsureUUID(instance, ec_id)
1109

    
1110
    instance.serial_no = 1
1111
    instance.ctime = instance.mtime = time.time()
1112
    self._config_data.instances[instance.name] = instance
1113
    self._config_data.cluster.serial_no += 1
1114
    self._UnlockedReleaseDRBDMinors(instance.name)
1115
    self._WriteConfig()
1116

    
1117
  def _EnsureUUID(self, item, ec_id):
1118
    """Ensures a given object has a valid UUID.
1119

1120
    @param item: the instance or node to be checked
1121
    @param ec_id: the execution context id for the uuid reservation
1122

1123
    """
1124
    if not item.uuid:
1125
      item.uuid = self._GenerateUniqueID(ec_id)
1126
    elif item.uuid in self._AllIDs(include_temporary=True):
1127
      raise errors.ConfigurationError("Cannot add '%s': UUID %s already"
1128
                                      " in use" % (item.name, item.uuid))
1129

    
1130
  def _SetInstanceStatus(self, instance_name, status):
1131
    """Set the instance's status to a given value.
1132

1133
    """
1134
    assert isinstance(status, bool), \
1135
           "Invalid status '%s' passed to SetInstanceStatus" % (status,)
1136

    
1137
    if instance_name not in self._config_data.instances:
1138
      raise errors.ConfigurationError("Unknown instance '%s'" %
1139
                                      instance_name)
1140
    instance = self._config_data.instances[instance_name]
1141
    if instance.admin_up != status:
1142
      instance.admin_up = status
1143
      instance.serial_no += 1
1144
      instance.mtime = time.time()
1145
      self._WriteConfig()
1146

    
1147
  @locking.ssynchronized(_config_lock)
1148
  def MarkInstanceUp(self, instance_name):
1149
    """Mark the instance status to up in the config.
1150

1151
    """
1152
    self._SetInstanceStatus(instance_name, True)
1153

    
1154
  @locking.ssynchronized(_config_lock)
1155
  def RemoveInstance(self, instance_name):
1156
    """Remove the instance from the configuration.
1157

1158
    """
1159
    if instance_name not in self._config_data.instances:
1160
      raise errors.ConfigurationError("Unknown instance '%s'" % instance_name)
1161
    del self._config_data.instances[instance_name]
1162
    self._config_data.cluster.serial_no += 1
1163
    self._WriteConfig()
1164

    
1165
  @locking.ssynchronized(_config_lock)
1166
  def RenameInstance(self, old_name, new_name):
1167
    """Rename an instance.
1168

1169
    This needs to be done in ConfigWriter and not by RemoveInstance
1170
    combined with AddInstance as only we can guarantee an atomic
1171
    rename.
1172

1173
    """
1174
    if old_name not in self._config_data.instances:
1175
      raise errors.ConfigurationError("Unknown instance '%s'" % old_name)
1176
    inst = self._config_data.instances[old_name]
1177
    del self._config_data.instances[old_name]
1178
    inst.name = new_name
1179

    
1180
    for disk in inst.disks:
1181
      if disk.dev_type == constants.LD_FILE:
1182
        # rename the file paths in logical and physical id
1183
        file_storage_dir = os.path.dirname(os.path.dirname(disk.logical_id[1]))
1184
        disk_fname = "disk%s" % disk.iv_name.split("/")[1]
1185
        disk.physical_id = disk.logical_id = (disk.logical_id[0],
1186
                                              utils.PathJoin(file_storage_dir,
1187
                                                             inst.name,
1188
                                                             disk_fname))
1189

    
1190
    # Force update of ssconf files
1191
    self._config_data.cluster.serial_no += 1
1192

    
1193
    self._config_data.instances[inst.name] = inst
1194
    self._WriteConfig()
1195

    
1196
  @locking.ssynchronized(_config_lock)
1197
  def MarkInstanceDown(self, instance_name):
1198
    """Mark the status of an instance to down in the configuration.
1199

1200
    """
1201
    self._SetInstanceStatus(instance_name, False)
1202

    
1203
  def _UnlockedGetInstanceList(self):
1204
    """Get the list of instances.
1205

1206
    This function is for internal use, when the config lock is already held.
1207

1208
    """
1209
    return self._config_data.instances.keys()
1210

    
1211
  @locking.ssynchronized(_config_lock, shared=1)
1212
  def GetInstanceList(self):
1213
    """Get the list of instances.
1214

1215
    @return: array of instances, ex. ['instance2.example.com',
1216
        'instance1.example.com']
1217

1218
    """
1219
    return self._UnlockedGetInstanceList()
1220

    
1221
  def ExpandInstanceName(self, short_name):
1222
    """Attempt to expand an incomplete instance name.
1223

1224
    """
1225
    # Locking is done in L{ConfigWriter.GetInstanceList}
1226
    return _MatchNameComponentIgnoreCase(short_name, self.GetInstanceList())
1227

    
1228
  def _UnlockedGetInstanceInfo(self, instance_name):
1229
    """Returns information about an instance.
1230

1231
    This function is for internal use, when the config lock is already held.
1232

1233
    """
1234
    if instance_name not in self._config_data.instances:
1235
      return None
1236

    
1237
    return self._config_data.instances[instance_name]
1238

    
1239
  @locking.ssynchronized(_config_lock, shared=1)
1240
  def GetInstanceInfo(self, instance_name):
1241
    """Returns information about an instance.
1242

1243
    It takes the information from the configuration file. Other information of
1244
    an instance are taken from the live systems.
1245

1246
    @param instance_name: name of the instance, e.g.
1247
        I{instance1.example.com}
1248

1249
    @rtype: L{objects.Instance}
1250
    @return: the instance object
1251

1252
    """
1253
    return self._UnlockedGetInstanceInfo(instance_name)
1254

    
1255
  @locking.ssynchronized(_config_lock, shared=1)
1256
  def GetInstanceNodeGroups(self, instance_name, primary_only=False):
1257
    """Returns set of node group UUIDs for instance's nodes.
1258

1259
    @rtype: frozenset
1260

1261
    """
1262
    instance = self._UnlockedGetInstanceInfo(instance_name)
1263
    if not instance:
1264
      raise errors.ConfigurationError("Unknown instance '%s'" % instance_name)
1265

    
1266
    if primary_only:
1267
      nodes = [instance.primary_node]
1268
    else:
1269
      nodes = instance.all_nodes
1270

    
1271
    return frozenset(self._UnlockedGetNodeInfo(node_name).group
1272
                     for node_name in nodes)
1273

    
1274
  @locking.ssynchronized(_config_lock, shared=1)
1275
  def GetMultiInstanceInfo(self, instances):
1276
    """Get the configuration of multiple instances.
1277

1278
    @param instances: list of instance names
1279
    @rtype: list
1280
    @return: list of tuples (instance, instance_info), where
1281
        instance_info is what would GetInstanceInfo return for the
1282
        node, while keeping the original order
1283

1284
    """
1285
    return [(name, self._UnlockedGetInstanceInfo(name)) for name in instances]
1286

    
1287
  @locking.ssynchronized(_config_lock, shared=1)
1288
  def GetAllInstancesInfo(self):
1289
    """Get the configuration of all instances.
1290

1291
    @rtype: dict
1292
    @return: dict of (instance, instance_info), where instance_info is what
1293
              would GetInstanceInfo return for the node
1294

1295
    """
1296
    my_dict = dict([(instance, self._UnlockedGetInstanceInfo(instance))
1297
                    for instance in self._UnlockedGetInstanceList()])
1298
    return my_dict
1299

    
1300
  @locking.ssynchronized(_config_lock)
1301
  def AddNode(self, node, ec_id):
1302
    """Add a node to the configuration.
1303

1304
    @type node: L{objects.Node}
1305
    @param node: a Node instance
1306

1307
    """
1308
    logging.info("Adding node %s to configuration", node.name)
1309

    
1310
    self._EnsureUUID(node, ec_id)
1311

    
1312
    node.serial_no = 1
1313
    node.ctime = node.mtime = time.time()
1314
    self._UnlockedAddNodeToGroup(node.name, node.group)
1315
    self._config_data.nodes[node.name] = node
1316
    self._config_data.cluster.serial_no += 1
1317
    self._WriteConfig()
1318

    
1319
  @locking.ssynchronized(_config_lock)
1320
  def RemoveNode(self, node_name):
1321
    """Remove a node from the configuration.
1322

1323
    """
1324
    logging.info("Removing node %s from configuration", node_name)
1325

    
1326
    if node_name not in self._config_data.nodes:
1327
      raise errors.ConfigurationError("Unknown node '%s'" % node_name)
1328

    
1329
    self._UnlockedRemoveNodeFromGroup(self._config_data.nodes[node_name])
1330
    del self._config_data.nodes[node_name]
1331
    self._config_data.cluster.serial_no += 1
1332
    self._WriteConfig()
1333

    
1334
  def ExpandNodeName(self, short_name):
1335
    """Attempt to expand an incomplete node name.
1336

1337
    """
1338
    # Locking is done in L{ConfigWriter.GetNodeList}
1339
    return _MatchNameComponentIgnoreCase(short_name, self.GetNodeList())
1340

    
1341
  def _UnlockedGetNodeInfo(self, node_name):
1342
    """Get the configuration of a node, as stored in the config.
1343

1344
    This function is for internal use, when the config lock is already
1345
    held.
1346

1347
    @param node_name: the node name, e.g. I{node1.example.com}
1348

1349
    @rtype: L{objects.Node}
1350
    @return: the node object
1351

1352
    """
1353
    if node_name not in self._config_data.nodes:
1354
      return None
1355

    
1356
    return self._config_data.nodes[node_name]
1357

    
1358
  @locking.ssynchronized(_config_lock, shared=1)
1359
  def GetNodeInfo(self, node_name):
1360
    """Get the configuration of a node, as stored in the config.
1361

1362
    This is just a locked wrapper over L{_UnlockedGetNodeInfo}.
1363

1364
    @param node_name: the node name, e.g. I{node1.example.com}
1365

1366
    @rtype: L{objects.Node}
1367
    @return: the node object
1368

1369
    """
1370
    return self._UnlockedGetNodeInfo(node_name)
1371

    
1372
  @locking.ssynchronized(_config_lock, shared=1)
1373
  def GetNodeInstances(self, node_name):
1374
    """Get the instances of a node, as stored in the config.
1375

1376
    @param node_name: the node name, e.g. I{node1.example.com}
1377

1378
    @rtype: (list, list)
1379
    @return: a tuple with two lists: the primary and the secondary instances
1380

1381
    """
1382
    pri = []
1383
    sec = []
1384
    for inst in self._config_data.instances.values():
1385
      if inst.primary_node == node_name:
1386
        pri.append(inst.name)
1387
      if node_name in inst.secondary_nodes:
1388
        sec.append(inst.name)
1389
    return (pri, sec)
1390

    
1391
  @locking.ssynchronized(_config_lock, shared=1)
1392
  def GetNodeGroupInstances(self, uuid, primary_only=False):
1393
    """Get the instances of a node group.
1394

1395
    @param uuid: Node group UUID
1396
    @param primary_only: Whether to only consider primary nodes
1397
    @rtype: frozenset
1398
    @return: List of instance names in node group
1399

1400
    """
1401
    if primary_only:
1402
      nodes_fn = lambda inst: [inst.primary_node]
1403
    else:
1404
      nodes_fn = lambda inst: inst.all_nodes
1405

    
1406
    return frozenset(inst.name
1407
                     for inst in self._config_data.instances.values()
1408
                     for node_name in nodes_fn(inst)
1409
                     if self._UnlockedGetNodeInfo(node_name).group == uuid)
1410

    
1411
  def _UnlockedGetNodeList(self):
1412
    """Return the list of nodes which are in the configuration.
1413

1414
    This function is for internal use, when the config lock is already
1415
    held.
1416

1417
    @rtype: list
1418

1419
    """
1420
    return self._config_data.nodes.keys()
1421

    
1422
  @locking.ssynchronized(_config_lock, shared=1)
1423
  def GetNodeList(self):
1424
    """Return the list of nodes which are in the configuration.
1425

1426
    """
1427
    return self._UnlockedGetNodeList()
1428

    
1429
  def _UnlockedGetOnlineNodeList(self):
1430
    """Return the list of nodes which are online.
1431

1432
    """
1433
    all_nodes = [self._UnlockedGetNodeInfo(node)
1434
                 for node in self._UnlockedGetNodeList()]
1435
    return [node.name for node in all_nodes if not node.offline]
1436

    
1437
  @locking.ssynchronized(_config_lock, shared=1)
1438
  def GetOnlineNodeList(self):
1439
    """Return the list of nodes which are online.
1440

1441
    """
1442
    return self._UnlockedGetOnlineNodeList()
1443

    
1444
  @locking.ssynchronized(_config_lock, shared=1)
1445
  def GetVmCapableNodeList(self):
1446
    """Return the list of nodes which are not vm capable.
1447

1448
    """
1449
    all_nodes = [self._UnlockedGetNodeInfo(node)
1450
                 for node in self._UnlockedGetNodeList()]
1451
    return [node.name for node in all_nodes if node.vm_capable]
1452

    
1453
  @locking.ssynchronized(_config_lock, shared=1)
1454
  def GetNonVmCapableNodeList(self):
1455
    """Return the list of nodes which are not vm capable.
1456

1457
    """
1458
    all_nodes = [self._UnlockedGetNodeInfo(node)
1459
                 for node in self._UnlockedGetNodeList()]
1460
    return [node.name for node in all_nodes if not node.vm_capable]
1461

    
1462
  @locking.ssynchronized(_config_lock, shared=1)
1463
  def GetMultiNodeInfo(self, nodes):
1464
    """Get the configuration of multiple nodes.
1465

1466
    @param nodes: list of node names
1467
    @rtype: list
1468
    @return: list of tuples of (node, node_info), where node_info is
1469
        what would GetNodeInfo return for the node, in the original
1470
        order
1471

1472
    """
1473
    return [(name, self._UnlockedGetNodeInfo(name)) for name in nodes]
1474

    
1475
  @locking.ssynchronized(_config_lock, shared=1)
1476
  def GetAllNodesInfo(self):
1477
    """Get the configuration of all nodes.
1478

1479
    @rtype: dict
1480
    @return: dict of (node, node_info), where node_info is what
1481
              would GetNodeInfo return for the node
1482

1483
    """
1484
    my_dict = dict([(node, self._UnlockedGetNodeInfo(node))
1485
                    for node in self._UnlockedGetNodeList()])
1486
    return my_dict
1487

    
1488
  @locking.ssynchronized(_config_lock, shared=1)
1489
  def GetNodeGroupsFromNodes(self, nodes):
1490
    """Returns groups for a list of nodes.
1491

1492
    @type nodes: list of string
1493
    @param nodes: List of node names
1494
    @rtype: frozenset
1495

1496
    """
1497
    return frozenset(self._UnlockedGetNodeInfo(name).group for name in nodes)
1498

    
1499
  def _UnlockedGetMasterCandidateStats(self, exceptions=None):
1500
    """Get the number of current and maximum desired and possible candidates.
1501

1502
    @type exceptions: list
1503
    @param exceptions: if passed, list of nodes that should be ignored
1504
    @rtype: tuple
1505
    @return: tuple of (current, desired and possible, possible)
1506

1507
    """
1508
    mc_now = mc_should = mc_max = 0
1509
    for node in self._config_data.nodes.values():
1510
      if exceptions and node.name in exceptions:
1511
        continue
1512
      if not (node.offline or node.drained) and node.master_capable:
1513
        mc_max += 1
1514
      if node.master_candidate:
1515
        mc_now += 1
1516
    mc_should = min(mc_max, self._config_data.cluster.candidate_pool_size)
1517
    return (mc_now, mc_should, mc_max)
1518

    
1519
  @locking.ssynchronized(_config_lock, shared=1)
1520
  def GetMasterCandidateStats(self, exceptions=None):
1521
    """Get the number of current and maximum possible candidates.
1522

1523
    This is just a wrapper over L{_UnlockedGetMasterCandidateStats}.
1524

1525
    @type exceptions: list
1526
    @param exceptions: if passed, list of nodes that should be ignored
1527
    @rtype: tuple
1528
    @return: tuple of (current, max)
1529

1530
    """
1531
    return self._UnlockedGetMasterCandidateStats(exceptions)
1532

    
1533
  @locking.ssynchronized(_config_lock)
1534
  def MaintainCandidatePool(self, exceptions):
1535
    """Try to grow the candidate pool to the desired size.
1536

1537
    @type exceptions: list
1538
    @param exceptions: if passed, list of nodes that should be ignored
1539
    @rtype: list
1540
    @return: list with the adjusted nodes (L{objects.Node} instances)
1541

1542
    """
1543
    mc_now, mc_max, _ = self._UnlockedGetMasterCandidateStats(exceptions)
1544
    mod_list = []
1545
    if mc_now < mc_max:
1546
      node_list = self._config_data.nodes.keys()
1547
      random.shuffle(node_list)
1548
      for name in node_list:
1549
        if mc_now >= mc_max:
1550
          break
1551
        node = self._config_data.nodes[name]
1552
        if (node.master_candidate or node.offline or node.drained or
1553
            node.name in exceptions or not node.master_capable):
1554
          continue
1555
        mod_list.append(node)
1556
        node.master_candidate = True
1557
        node.serial_no += 1
1558
        mc_now += 1
1559
      if mc_now != mc_max:
1560
        # this should not happen
1561
        logging.warning("Warning: MaintainCandidatePool didn't manage to"
1562
                        " fill the candidate pool (%d/%d)", mc_now, mc_max)
1563
      if mod_list:
1564
        self._config_data.cluster.serial_no += 1
1565
        self._WriteConfig()
1566

    
1567
    return mod_list
1568

    
1569
  def _UnlockedAddNodeToGroup(self, node_name, nodegroup_uuid):
1570
    """Add a given node to the specified group.
1571

1572
    """
1573
    if nodegroup_uuid not in self._config_data.nodegroups:
1574
      # This can happen if a node group gets deleted between its lookup and
1575
      # when we're adding the first node to it, since we don't keep a lock in
1576
      # the meantime. It's ok though, as we'll fail cleanly if the node group
1577
      # is not found anymore.
1578
      raise errors.OpExecError("Unknown node group: %s" % nodegroup_uuid)
1579
    if node_name not in self._config_data.nodegroups[nodegroup_uuid].members:
1580
      self._config_data.nodegroups[nodegroup_uuid].members.append(node_name)
1581

    
1582
  def _UnlockedRemoveNodeFromGroup(self, node):
1583
    """Remove a given node from its group.
1584

1585
    """
1586
    nodegroup = node.group
1587
    if nodegroup not in self._config_data.nodegroups:
1588
      logging.warning("Warning: node '%s' has unknown node group '%s'"
1589
                      " (while being removed from it)", node.name, nodegroup)
1590
    nodegroup_obj = self._config_data.nodegroups[nodegroup]
1591
    if node.name not in nodegroup_obj.members:
1592
      logging.warning("Warning: node '%s' not a member of its node group '%s'"
1593
                      " (while being removed from it)", node.name, nodegroup)
1594
    else:
1595
      nodegroup_obj.members.remove(node.name)
1596

    
1597
  def _BumpSerialNo(self):
1598
    """Bump up the serial number of the config.
1599

1600
    """
1601
    self._config_data.serial_no += 1
1602
    self._config_data.mtime = time.time()
1603

    
1604
  def _AllUUIDObjects(self):
1605
    """Returns all objects with uuid attributes.
1606

1607
    """
1608
    return (self._config_data.instances.values() +
1609
            self._config_data.nodes.values() +
1610
            self._config_data.nodegroups.values() +
1611
            [self._config_data.cluster])
1612

    
1613
  def _OpenConfig(self, accept_foreign):
1614
    """Read the config data from disk.
1615

1616
    """
1617
    raw_data = utils.ReadFile(self._cfg_file)
1618

    
1619
    try:
1620
      data = objects.ConfigData.FromDict(serializer.Load(raw_data))
1621
    except Exception, err:
1622
      raise errors.ConfigurationError(err)
1623

    
1624
    # Make sure the configuration has the right version
1625
    _ValidateConfig(data)
1626

    
1627
    if (not hasattr(data, 'cluster') or
1628
        not hasattr(data.cluster, 'rsahostkeypub')):
1629
      raise errors.ConfigurationError("Incomplete configuration"
1630
                                      " (missing cluster.rsahostkeypub)")
1631

    
1632
    if data.cluster.master_node != self._my_hostname and not accept_foreign:
1633
      msg = ("The configuration denotes node %s as master, while my"
1634
             " hostname is %s; opening a foreign configuration is only"
1635
             " possible in accept_foreign mode" %
1636
             (data.cluster.master_node, self._my_hostname))
1637
      raise errors.ConfigurationError(msg)
1638

    
1639
    # Upgrade configuration if needed
1640
    data.UpgradeConfig()
1641

    
1642
    self._config_data = data
1643
    # reset the last serial as -1 so that the next write will cause
1644
    # ssconf update
1645
    self._last_cluster_serial = -1
1646

    
1647
    # And finally run our (custom) config upgrade sequence
1648
    self._UpgradeConfig()
1649

    
1650
    self._cfg_id = utils.GetFileID(path=self._cfg_file)
1651

    
1652
  def _UpgradeConfig(self):
1653
    """Run upgrade steps that cannot be done purely in the objects.
1654

1655
    This is because some data elements need uniqueness across the
1656
    whole configuration, etc.
1657

1658
    @warning: this function will call L{_WriteConfig()}, but also
1659
        L{DropECReservations} so it needs to be called only from a
1660
        "safe" place (the constructor). If one wanted to call it with
1661
        the lock held, a DropECReservationUnlocked would need to be
1662
        created first, to avoid causing deadlock.
1663

1664
    """
1665
    modified = False
1666
    for item in self._AllUUIDObjects():
1667
      if item.uuid is None:
1668
        item.uuid = self._GenerateUniqueID(_UPGRADE_CONFIG_JID)
1669
        modified = True
1670
    if not self._config_data.nodegroups:
1671
      default_nodegroup_name = constants.INITIAL_NODE_GROUP_NAME
1672
      default_nodegroup = objects.NodeGroup(name=default_nodegroup_name,
1673
                                            members=[])
1674
      self._UnlockedAddNodeGroup(default_nodegroup, _UPGRADE_CONFIG_JID, True)
1675
      modified = True
1676
    for node in self._config_data.nodes.values():
1677
      if not node.group:
1678
        node.group = self.LookupNodeGroup(None)
1679
        modified = True
1680
      # This is technically *not* an upgrade, but needs to be done both when
1681
      # nodegroups are being added, and upon normally loading the config,
1682
      # because the members list of a node group is discarded upon
1683
      # serializing/deserializing the object.
1684
      self._UnlockedAddNodeToGroup(node.name, node.group)
1685
    if modified:
1686
      self._WriteConfig()
1687
      # This is ok even if it acquires the internal lock, as _UpgradeConfig is
1688
      # only called at config init time, without the lock held
1689
      self.DropECReservations(_UPGRADE_CONFIG_JID)
1690

    
1691
  def _DistributeConfig(self, feedback_fn):
1692
    """Distribute the configuration to the other nodes.
1693

1694
    Currently, this only copies the configuration file. In the future,
1695
    it could be used to encapsulate the 2/3-phase update mechanism.
1696

1697
    """
1698
    if self._offline:
1699
      return True
1700

    
1701
    bad = False
1702

    
1703
    node_list = []
1704
    addr_list = []
1705
    myhostname = self._my_hostname
1706
    # we can skip checking whether _UnlockedGetNodeInfo returns None
1707
    # since the node list comes from _UnlocketGetNodeList, and we are
1708
    # called with the lock held, so no modifications should take place
1709
    # in between
1710
    for node_name in self._UnlockedGetNodeList():
1711
      if node_name == myhostname:
1712
        continue
1713
      node_info = self._UnlockedGetNodeInfo(node_name)
1714
      if not node_info.master_candidate:
1715
        continue
1716
      node_list.append(node_info.name)
1717
      addr_list.append(node_info.primary_ip)
1718

    
1719
    result = rpc.RpcRunner.call_upload_file(node_list, self._cfg_file,
1720
                                            address_list=addr_list)
1721
    for to_node, to_result in result.items():
1722
      msg = to_result.fail_msg
1723
      if msg:
1724
        msg = ("Copy of file %s to node %s failed: %s" %
1725
               (self._cfg_file, to_node, msg))
1726
        logging.error(msg)
1727

    
1728
        if feedback_fn:
1729
          feedback_fn(msg)
1730

    
1731
        bad = True
1732

    
1733
    return not bad
1734

    
1735
  def _WriteConfig(self, destination=None, feedback_fn=None):
1736
    """Write the configuration data to persistent storage.
1737

1738
    """
1739
    assert feedback_fn is None or callable(feedback_fn)
1740

    
1741
    # Warn on config errors, but don't abort the save - the
1742
    # configuration has already been modified, and we can't revert;
1743
    # the best we can do is to warn the user and save as is, leaving
1744
    # recovery to the user
1745
    config_errors = self._UnlockedVerifyConfig()
1746
    if config_errors:
1747
      errmsg = ("Configuration data is not consistent: %s" %
1748
                (utils.CommaJoin(config_errors)))
1749
      logging.critical(errmsg)
1750
      if feedback_fn:
1751
        feedback_fn(errmsg)
1752

    
1753
    if destination is None:
1754
      destination = self._cfg_file
1755
    self._BumpSerialNo()
1756
    txt = serializer.Dump(self._config_data.ToDict())
1757

    
1758
    getents = self._getents()
1759
    try:
1760
      fd = utils.SafeWriteFile(destination, self._cfg_id, data=txt,
1761
                               close=False, gid=getents.confd_gid, mode=0640)
1762
    except errors.LockError:
1763
      raise errors.ConfigurationError("The configuration file has been"
1764
                                      " modified since the last write, cannot"
1765
                                      " update")
1766
    try:
1767
      self._cfg_id = utils.GetFileID(fd=fd)
1768
    finally:
1769
      os.close(fd)
1770

    
1771
    self.write_count += 1
1772

    
1773
    # and redistribute the config file to master candidates
1774
    self._DistributeConfig(feedback_fn)
1775

    
1776
    # Write ssconf files on all nodes (including locally)
1777
    if self._last_cluster_serial < self._config_data.cluster.serial_no:
1778
      if not self._offline:
1779
        result = rpc.RpcRunner.call_write_ssconf_files(
1780
          self._UnlockedGetOnlineNodeList(),
1781
          self._UnlockedGetSsconfValues())
1782

    
1783
        for nname, nresu in result.items():
1784
          msg = nresu.fail_msg
1785
          if msg:
1786
            errmsg = ("Error while uploading ssconf files to"
1787
                      " node %s: %s" % (nname, msg))
1788
            logging.warning(errmsg)
1789

    
1790
            if feedback_fn:
1791
              feedback_fn(errmsg)
1792

    
1793
      self._last_cluster_serial = self._config_data.cluster.serial_no
1794

    
1795
  def _UnlockedGetSsconfValues(self):
1796
    """Return the values needed by ssconf.
1797

1798
    @rtype: dict
1799
    @return: a dictionary with keys the ssconf names and values their
1800
        associated value
1801

1802
    """
1803
    fn = "\n".join
1804
    instance_names = utils.NiceSort(self._UnlockedGetInstanceList())
1805
    node_names = utils.NiceSort(self._UnlockedGetNodeList())
1806
    node_info = [self._UnlockedGetNodeInfo(name) for name in node_names]
1807
    node_pri_ips = ["%s %s" % (ninfo.name, ninfo.primary_ip)
1808
                    for ninfo in node_info]
1809
    node_snd_ips = ["%s %s" % (ninfo.name, ninfo.secondary_ip)
1810
                    for ninfo in node_info]
1811

    
1812
    instance_data = fn(instance_names)
1813
    off_data = fn(node.name for node in node_info if node.offline)
1814
    on_data = fn(node.name for node in node_info if not node.offline)
1815
    mc_data = fn(node.name for node in node_info if node.master_candidate)
1816
    mc_ips_data = fn(node.primary_ip for node in node_info
1817
                     if node.master_candidate)
1818
    node_data = fn(node_names)
1819
    node_pri_ips_data = fn(node_pri_ips)
1820
    node_snd_ips_data = fn(node_snd_ips)
1821

    
1822
    cluster = self._config_data.cluster
1823
    cluster_tags = fn(cluster.GetTags())
1824

    
1825
    hypervisor_list = fn(cluster.enabled_hypervisors)
1826

    
1827
    uid_pool = uidpool.FormatUidPool(cluster.uid_pool, separator="\n")
1828

    
1829
    nodegroups = ["%s %s" % (nodegroup.uuid, nodegroup.name) for nodegroup in
1830
                  self._config_data.nodegroups.values()]
1831
    nodegroups_data = fn(utils.NiceSort(nodegroups))
1832

    
1833
    ssconf_values = {
1834
      constants.SS_CLUSTER_NAME: cluster.cluster_name,
1835
      constants.SS_CLUSTER_TAGS: cluster_tags,
1836
      constants.SS_FILE_STORAGE_DIR: cluster.file_storage_dir,
1837
      constants.SS_SHARED_FILE_STORAGE_DIR: cluster.shared_file_storage_dir,
1838
      constants.SS_MASTER_CANDIDATES: mc_data,
1839
      constants.SS_MASTER_CANDIDATES_IPS: mc_ips_data,
1840
      constants.SS_MASTER_IP: cluster.master_ip,
1841
      constants.SS_MASTER_NETDEV: cluster.master_netdev,
1842
      constants.SS_MASTER_NODE: cluster.master_node,
1843
      constants.SS_NODE_LIST: node_data,
1844
      constants.SS_NODE_PRIMARY_IPS: node_pri_ips_data,
1845
      constants.SS_NODE_SECONDARY_IPS: node_snd_ips_data,
1846
      constants.SS_OFFLINE_NODES: off_data,
1847
      constants.SS_ONLINE_NODES: on_data,
1848
      constants.SS_PRIMARY_IP_FAMILY: str(cluster.primary_ip_family),
1849
      constants.SS_INSTANCE_LIST: instance_data,
1850
      constants.SS_RELEASE_VERSION: constants.RELEASE_VERSION,
1851
      constants.SS_HYPERVISOR_LIST: hypervisor_list,
1852
      constants.SS_MAINTAIN_NODE_HEALTH: str(cluster.maintain_node_health),
1853
      constants.SS_UID_POOL: uid_pool,
1854
      constants.SS_NODEGROUPS: nodegroups_data,
1855
      }
1856
    bad_values = [(k, v) for k, v in ssconf_values.items()
1857
                  if not isinstance(v, (str, basestring))]
1858
    if bad_values:
1859
      err = utils.CommaJoin("%s=%s" % (k, v) for k, v in bad_values)
1860
      raise errors.ConfigurationError("Some ssconf key(s) have non-string"
1861
                                      " values: %s" % err)
1862
    return ssconf_values
1863

    
1864
  @locking.ssynchronized(_config_lock, shared=1)
1865
  def GetSsconfValues(self):
1866
    """Wrapper using lock around _UnlockedGetSsconf().
1867

1868
    """
1869
    return self._UnlockedGetSsconfValues()
1870

    
1871
  @locking.ssynchronized(_config_lock, shared=1)
1872
  def GetVGName(self):
1873
    """Return the volume group name.
1874

1875
    """
1876
    return self._config_data.cluster.volume_group_name
1877

    
1878
  @locking.ssynchronized(_config_lock)
1879
  def SetVGName(self, vg_name):
1880
    """Set the volume group name.
1881

1882
    """
1883
    self._config_data.cluster.volume_group_name = vg_name
1884
    self._config_data.cluster.serial_no += 1
1885
    self._WriteConfig()
1886

    
1887
  @locking.ssynchronized(_config_lock, shared=1)
1888
  def GetDRBDHelper(self):
1889
    """Return DRBD usermode helper.
1890

1891
    """
1892
    return self._config_data.cluster.drbd_usermode_helper
1893

    
1894
  @locking.ssynchronized(_config_lock)
1895
  def SetDRBDHelper(self, drbd_helper):
1896
    """Set DRBD usermode helper.
1897

1898
    """
1899
    self._config_data.cluster.drbd_usermode_helper = drbd_helper
1900
    self._config_data.cluster.serial_no += 1
1901
    self._WriteConfig()
1902

    
1903
  @locking.ssynchronized(_config_lock, shared=1)
1904
  def GetMACPrefix(self):
1905
    """Return the mac prefix.
1906

1907
    """
1908
    return self._config_data.cluster.mac_prefix
1909

    
1910
  @locking.ssynchronized(_config_lock, shared=1)
1911
  def GetClusterInfo(self):
1912
    """Returns information about the cluster
1913

1914
    @rtype: L{objects.Cluster}
1915
    @return: the cluster object
1916

1917
    """
1918
    return self._config_data.cluster
1919

    
1920
  @locking.ssynchronized(_config_lock, shared=1)
1921
  def HasAnyDiskOfType(self, dev_type):
1922
    """Check if in there is at disk of the given type in the configuration.
1923

1924
    """
1925
    return self._config_data.HasAnyDiskOfType(dev_type)
1926

    
1927
  @locking.ssynchronized(_config_lock)
1928
  def Update(self, target, feedback_fn):
1929
    """Notify function to be called after updates.
1930

1931
    This function must be called when an object (as returned by
1932
    GetInstanceInfo, GetNodeInfo, GetCluster) has been updated and the
1933
    caller wants the modifications saved to the backing store. Note
1934
    that all modified objects will be saved, but the target argument
1935
    is the one the caller wants to ensure that it's saved.
1936

1937
    @param target: an instance of either L{objects.Cluster},
1938
        L{objects.Node} or L{objects.Instance} which is existing in
1939
        the cluster
1940
    @param feedback_fn: Callable feedback function
1941

1942
    """
1943
    if self._config_data is None:
1944
      raise errors.ProgrammerError("Configuration file not read,"
1945
                                   " cannot save.")
1946
    update_serial = False
1947
    if isinstance(target, objects.Cluster):
1948
      test = target == self._config_data.cluster
1949
    elif isinstance(target, objects.Node):
1950
      test = target in self._config_data.nodes.values()
1951
      update_serial = True
1952
    elif isinstance(target, objects.Instance):
1953
      test = target in self._config_data.instances.values()
1954
    elif isinstance(target, objects.NodeGroup):
1955
      test = target in self._config_data.nodegroups.values()
1956
    else:
1957
      raise errors.ProgrammerError("Invalid object type (%s) passed to"
1958
                                   " ConfigWriter.Update" % type(target))
1959
    if not test:
1960
      raise errors.ConfigurationError("Configuration updated since object"
1961
                                      " has been read or unknown object")
1962
    target.serial_no += 1
1963
    target.mtime = now = time.time()
1964

    
1965
    if update_serial:
1966
      # for node updates, we need to increase the cluster serial too
1967
      self._config_data.cluster.serial_no += 1
1968
      self._config_data.cluster.mtime = now
1969

    
1970
    if isinstance(target, objects.Instance):
1971
      self._UnlockedReleaseDRBDMinors(target.name)
1972

    
1973
    self._WriteConfig(feedback_fn=feedback_fn)
1974

    
1975
  @locking.ssynchronized(_config_lock)
1976
  def DropECReservations(self, ec_id):
1977
    """Drop per-execution-context reservations
1978

1979
    """
1980
    for rm in self._all_rms:
1981
      rm.DropECReservations(ec_id)