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#
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#
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# Copyright (C) 2006, 2007 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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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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_config_lock = locking.SharedLock()
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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.ConfigurationError("Cluster configuration version"
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                                    " mismatch, got %s instead of %s" %
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                                    (data.version,
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                                     constants.CONFIG_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.items():
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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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                                    (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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108
    """
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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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124

    
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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
130

131
  """
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  def __init__(self, cfg_file=None, offline=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._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 = utils.HostInfo().name
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    self._last_cluster_serial = -1
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    self._OpenConfig()
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156
  # 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():
159
    """Check if the cluster is configured.
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161
    """
162
    return os.path.exists(constants.CLUSTER_CONF_FILE)
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164
  def _GenerateOneMAC(self):
165
    """Generate one mac address
166

167
    """
168
    prefix = self._config_data.cluster.mac_prefix
169
    byte1 = random.randrange(0, 256)
170
    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)
173
    return mac
174

    
175
  @locking.ssynchronized(_config_lock, shared=1)
176
  def GenerateMAC(self, ec_id):
177
    """Generate a MAC for an instance.
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179
    This should check the current instances for duplicates.
180

181
    """
182
    existing = self._AllMACs()
183
    return self._temporary_ids.Generate(existing, self._GenerateOneMAC, ec_id)
184

    
185
  @locking.ssynchronized(_config_lock, shared=1)
186
  def ReserveMAC(self, mac, ec_id):
187
    """Reserve a MAC for an instance.
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189
    This only checks instances managed by this cluster, it does not
190
    check for potential collisions elsewhere.
191

192
    """
193
    all_macs = self._AllMACs()
194
    if mac in all_macs:
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      raise errors.ReservationError("mac already in use")
196
    else:
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      self._temporary_macs.Reserve(mac, ec_id)
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199
  @locking.ssynchronized(_config_lock, shared=1)
200
  def ReserveLV(self, lv_name, ec_id):
201
    """Reserve an VG/LV pair for an instance.
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203
    @type lv_name: string
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    @param lv_name: the logical volume name to reserve
205

206
    """
207
    all_lvs = self._AllLVs()
208
    if lv_name in all_lvs:
209
      raise errors.ReservationError("LV already in use")
210
    else:
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      self._temporary_lvs.Reserve(lv_name, ec_id)
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213
  @locking.ssynchronized(_config_lock, shared=1)
214
  def GenerateDRBDSecret(self, ec_id):
215
    """Generate a DRBD secret.
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217
    This checks the current disks for duplicates.
218

219
    """
220
    return self._temporary_secrets.Generate(self._AllDRBDSecrets(),
221
                                            utils.GenerateSecret,
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                                            ec_id)
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224
  def _AllLVs(self):
225
    """Compute the list of all LVs.
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227
    """
228
    lvnames = set()
229
    for instance in self._config_data.instances.values():
230
      node_data = instance.MapLVsByNode()
231
      for lv_list in node_data.values():
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        lvnames.update(lv_list)
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    return lvnames
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235
  def _AllIDs(self, include_temporary):
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    """Compute the list of all UUIDs and names we have.
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238
    @type include_temporary: boolean
239
    @param include_temporary: whether to include the _temporary_ids set
240
    @rtype: set
241
    @return: a set of IDs
242

243
    """
244
    existing = set()
245
    if include_temporary:
246
      existing.update(self._temporary_ids.GetReserved())
247
    existing.update(self._AllLVs())
248
    existing.update(self._config_data.instances.keys())
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    existing.update(self._config_data.nodes.keys())
250
    existing.update([i.uuid for i in self._AllUUIDObjects() if i.uuid])
251
    return existing
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253
  def _GenerateUniqueID(self, ec_id):
254
    """Generate an unique UUID.
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256
    This checks the current node, instances and disk names for
257
    duplicates.
258

259
    @rtype: string
260
    @return: the unique id
261

262
    """
263
    existing = self._AllIDs(include_temporary=False)
264
    return self._temporary_ids.Generate(existing, utils.NewUUID, ec_id)
265

    
266
  @locking.ssynchronized(_config_lock, shared=1)
267
  def GenerateUniqueID(self, ec_id):
268
    """Generate an unique ID.
269

270
    This is just a wrapper over the unlocked version.
271

272
    @type ec_id: string
273
    @param ec_id: unique id for the job to reserve the id to
274

275
    """
276
    return self._GenerateUniqueID(ec_id)
277

    
278
  def _AllMACs(self):
279
    """Return all MACs present in the config.
280

281
    @rtype: list
282
    @return: the list of all MACs
283

284
    """
285
    result = []
286
    for instance in self._config_data.instances.values():
287
      for nic in instance.nics:
288
        result.append(nic.mac)
289

    
290
    return result
291

    
292
  def _AllDRBDSecrets(self):
293
    """Return all DRBD secrets present in the config.
294

295
    @rtype: list
296
    @return: the list of all DRBD secrets
297

298
    """
299
    def helper(disk, result):
300
      """Recursively gather secrets from this disk."""
301
      if disk.dev_type == constants.DT_DRBD8:
302
        result.append(disk.logical_id[5])
303
      if disk.children:
304
        for child in disk.children:
305
          helper(child, result)
306

    
307
    result = []
308
    for instance in self._config_data.instances.values():
309
      for disk in instance.disks:
310
        helper(disk, result)
311

    
312
    return result
313

    
314
  def _CheckDiskIDs(self, disk, l_ids, p_ids):
315
    """Compute duplicate disk IDs
316

317
    @type disk: L{objects.Disk}
318
    @param disk: the disk at which to start searching
319
    @type l_ids: list
320
    @param l_ids: list of current logical ids
321
    @type p_ids: list
322
    @param p_ids: list of current physical ids
323
    @rtype: list
324
    @return: a list of error messages
325

326
    """
327
    result = []
328
    if disk.logical_id is not None:
329
      if disk.logical_id in l_ids:
330
        result.append("duplicate logical id %s" % str(disk.logical_id))
331
      else:
332
        l_ids.append(disk.logical_id)
333
    if disk.physical_id is not None:
334
      if disk.physical_id in p_ids:
335
        result.append("duplicate physical id %s" % str(disk.physical_id))
336
      else:
337
        p_ids.append(disk.physical_id)
338

    
339
    if disk.children:
340
      for child in disk.children:
341
        result.extend(self._CheckDiskIDs(child, l_ids, p_ids))
342
    return result
343

    
344
  def _UnlockedVerifyConfig(self):
345
    """Verify function.
346

347
    @rtype: list
348
    @return: a list of error messages; a non-empty list signifies
349
        configuration errors
350

351
    """
352
    result = []
353
    seen_macs = []
354
    ports = {}
355
    data = self._config_data
356
    seen_lids = []
357
    seen_pids = []
358

    
359
    # global cluster checks
360
    if not data.cluster.enabled_hypervisors:
361
      result.append("enabled hypervisors list doesn't have any entries")
362
    invalid_hvs = set(data.cluster.enabled_hypervisors) - constants.HYPER_TYPES
363
    if invalid_hvs:
364
      result.append("enabled hypervisors contains invalid entries: %s" %
365
                    invalid_hvs)
366

    
367
    if data.cluster.master_node not in data.nodes:
368
      result.append("cluster has invalid primary node '%s'" %
369
                    data.cluster.master_node)
370

    
371
    # per-instance checks
372
    for instance_name in data.instances:
373
      instance = data.instances[instance_name]
374
      if instance.name != instance_name:
375
        result.append("instance '%s' is indexed by wrong name '%s'" %
376
                      (instance.name, instance_name))
377
      if instance.primary_node not in data.nodes:
378
        result.append("instance '%s' has invalid primary node '%s'" %
379
                      (instance_name, instance.primary_node))
380
      for snode in instance.secondary_nodes:
381
        if snode not in data.nodes:
382
          result.append("instance '%s' has invalid secondary node '%s'" %
383
                        (instance_name, snode))
384
      for idx, nic in enumerate(instance.nics):
385
        if nic.mac in seen_macs:
386
          result.append("instance '%s' has NIC %d mac %s duplicate" %
387
                        (instance_name, idx, nic.mac))
388
        else:
389
          seen_macs.append(nic.mac)
390

    
391
      # gather the drbd ports for duplicate checks
392
      for dsk in instance.disks:
393
        if dsk.dev_type in constants.LDS_DRBD:
394
          tcp_port = dsk.logical_id[2]
395
          if tcp_port not in ports:
396
            ports[tcp_port] = []
397
          ports[tcp_port].append((instance.name, "drbd disk %s" % dsk.iv_name))
398
      # gather network port reservation
399
      net_port = getattr(instance, "network_port", None)
400
      if net_port is not None:
401
        if net_port not in ports:
402
          ports[net_port] = []
403
        ports[net_port].append((instance.name, "network port"))
404

    
405
      # instance disk verify
406
      for idx, disk in enumerate(instance.disks):
407
        result.extend(["instance '%s' disk %d error: %s" %
408
                       (instance.name, idx, msg) for msg in disk.Verify()])
409
        result.extend(self._CheckDiskIDs(disk, seen_lids, seen_pids))
410

    
411
    # cluster-wide pool of free ports
412
    for free_port in data.cluster.tcpudp_port_pool:
413
      if free_port not in ports:
414
        ports[free_port] = []
415
      ports[free_port].append(("cluster", "port marked as free"))
416

    
417
    # compute tcp/udp duplicate ports
418
    keys = ports.keys()
419
    keys.sort()
420
    for pnum in keys:
421
      pdata = ports[pnum]
422
      if len(pdata) > 1:
423
        txt = utils.CommaJoin(["%s/%s" % val for val in pdata])
424
        result.append("tcp/udp port %s has duplicates: %s" % (pnum, txt))
425

    
426
    # highest used tcp port check
427
    if keys:
428
      if keys[-1] > data.cluster.highest_used_port:
429
        result.append("Highest used port mismatch, saved %s, computed %s" %
430
                      (data.cluster.highest_used_port, keys[-1]))
431

    
432
    if not data.nodes[data.cluster.master_node].master_candidate:
433
      result.append("Master node is not a master candidate")
434

    
435
    # master candidate checks
436
    mc_now, mc_max, _ = self._UnlockedGetMasterCandidateStats()
437
    if mc_now < mc_max:
438
      result.append("Not enough master candidates: actual %d, target %d" %
439
                    (mc_now, mc_max))
440

    
441
    # node checks
442
    for node_name, node in data.nodes.items():
443
      if node.name != node_name:
444
        result.append("Node '%s' is indexed by wrong name '%s'" %
445
                      (node.name, node_name))
446
      if [node.master_candidate, node.drained, node.offline].count(True) > 1:
447
        result.append("Node %s state is invalid: master_candidate=%s,"
448
                      " drain=%s, offline=%s" %
449
                      (node.name, node.master_candidate, node.drain,
450
                       node.offline))
451

    
452
    # drbd minors check
453
    _, duplicates = self._UnlockedComputeDRBDMap()
454
    for node, minor, instance_a, instance_b in duplicates:
455
      result.append("DRBD minor %d on node %s is assigned twice to instances"
456
                    " %s and %s" % (minor, node, instance_a, instance_b))
457

    
458
    # IP checks
459
    default_nicparams = data.cluster.nicparams[constants.PP_DEFAULT]
460
    ips = {}
461

    
462
    def _AddIpAddress(ip, name):
463
      ips.setdefault(ip, []).append(name)
464

    
465
    _AddIpAddress(data.cluster.master_ip, "cluster_ip")
466

    
467
    for node in data.nodes.values():
468
      _AddIpAddress(node.primary_ip, "node:%s/primary" % node.name)
469
      if node.secondary_ip != node.primary_ip:
470
        _AddIpAddress(node.secondary_ip, "node:%s/secondary" % node.name)
471

    
472
    for instance in data.instances.values():
473
      for idx, nic in enumerate(instance.nics):
474
        if nic.ip is None:
475
          continue
476

    
477
        nicparams = objects.FillDict(default_nicparams, nic.nicparams)
478
        nic_mode = nicparams[constants.NIC_MODE]
479
        nic_link = nicparams[constants.NIC_LINK]
480

    
481
        if nic_mode == constants.NIC_MODE_BRIDGED:
482
          link = "bridge:%s" % nic_link
483
        elif nic_mode == constants.NIC_MODE_ROUTED:
484
          link = "route:%s" % nic_link
485
        else:
486
          raise errors.ProgrammerError("NIC mode '%s' not handled" % nic_mode)
487

    
488
        _AddIpAddress("%s/%s" % (link, nic.ip),
489
                      "instance:%s/nic:%d" % (instance.name, idx))
490

    
491
    for ip, owners in ips.items():
492
      if len(owners) > 1:
493
        result.append("IP address %s is used by multiple owners: %s" %
494
                      (ip, utils.CommaJoin(owners)))
495

    
496
    return result
497

    
498
  @locking.ssynchronized(_config_lock, shared=1)
499
  def VerifyConfig(self):
500
    """Verify function.
501

502
    This is just a wrapper over L{_UnlockedVerifyConfig}.
503

504
    @rtype: list
505
    @return: a list of error messages; a non-empty list signifies
506
        configuration errors
507

508
    """
509
    return self._UnlockedVerifyConfig()
510

    
511
  def _UnlockedSetDiskID(self, disk, node_name):
512
    """Convert the unique ID to the ID needed on the target nodes.
513

514
    This is used only for drbd, which needs ip/port configuration.
515

516
    The routine descends down and updates its children also, because
517
    this helps when the only the top device is passed to the remote
518
    node.
519

520
    This function is for internal use, when the config lock is already held.
521

522
    """
523
    if disk.children:
524
      for child in disk.children:
525
        self._UnlockedSetDiskID(child, node_name)
526

    
527
    if disk.logical_id is None and disk.physical_id is not None:
528
      return
529
    if disk.dev_type == constants.LD_DRBD8:
530
      pnode, snode, port, pminor, sminor, secret = disk.logical_id
531
      if node_name not in (pnode, snode):
532
        raise errors.ConfigurationError("DRBD device not knowing node %s" %
533
                                        node_name)
534
      pnode_info = self._UnlockedGetNodeInfo(pnode)
535
      snode_info = self._UnlockedGetNodeInfo(snode)
536
      if pnode_info is None or snode_info is None:
537
        raise errors.ConfigurationError("Can't find primary or secondary node"
538
                                        " for %s" % str(disk))
539
      p_data = (pnode_info.secondary_ip, port)
540
      s_data = (snode_info.secondary_ip, port)
541
      if pnode == node_name:
542
        disk.physical_id = p_data + s_data + (pminor, secret)
543
      else: # it must be secondary, we tested above
544
        disk.physical_id = s_data + p_data + (sminor, secret)
545
    else:
546
      disk.physical_id = disk.logical_id
547
    return
548

    
549
  @locking.ssynchronized(_config_lock)
550
  def SetDiskID(self, disk, node_name):
551
    """Convert the unique ID to the ID needed on the target nodes.
552

553
    This is used only for drbd, which needs ip/port configuration.
554

555
    The routine descends down and updates its children also, because
556
    this helps when the only the top device is passed to the remote
557
    node.
558

559
    """
560
    return self._UnlockedSetDiskID(disk, node_name)
561

    
562
  @locking.ssynchronized(_config_lock)
563
  def AddTcpUdpPort(self, port):
564
    """Adds a new port to the available port pool.
565

566
    """
567
    if not isinstance(port, int):
568
      raise errors.ProgrammerError("Invalid type passed for port")
569

    
570
    self._config_data.cluster.tcpudp_port_pool.add(port)
571
    self._WriteConfig()
572

    
573
  @locking.ssynchronized(_config_lock, shared=1)
574
  def GetPortList(self):
575
    """Returns a copy of the current port list.
576

577
    """
578
    return self._config_data.cluster.tcpudp_port_pool.copy()
579

    
580
  @locking.ssynchronized(_config_lock)
581
  def AllocatePort(self):
582
    """Allocate a port.
583

584
    The port will be taken from the available port pool or from the
585
    default port range (and in this case we increase
586
    highest_used_port).
587

588
    """
589
    # If there are TCP/IP ports configured, we use them first.
590
    if self._config_data.cluster.tcpudp_port_pool:
591
      port = self._config_data.cluster.tcpudp_port_pool.pop()
592
    else:
593
      port = self._config_data.cluster.highest_used_port + 1
594
      if port >= constants.LAST_DRBD_PORT:
595
        raise errors.ConfigurationError("The highest used port is greater"
596
                                        " than %s. Aborting." %
597
                                        constants.LAST_DRBD_PORT)
598
      self._config_data.cluster.highest_used_port = port
599

    
600
    self._WriteConfig()
601
    return port
602

    
603
  def _UnlockedComputeDRBDMap(self):
604
    """Compute the used DRBD minor/nodes.
605

606
    @rtype: (dict, list)
607
    @return: dictionary of node_name: dict of minor: instance_name;
608
        the returned dict will have all the nodes in it (even if with
609
        an empty list), and a list of duplicates; if the duplicates
610
        list is not empty, the configuration is corrupted and its caller
611
        should raise an exception
612

613
    """
614
    def _AppendUsedPorts(instance_name, disk, used):
615
      duplicates = []
616
      if disk.dev_type == constants.LD_DRBD8 and len(disk.logical_id) >= 5:
617
        node_a, node_b, _, minor_a, minor_b = disk.logical_id[:5]
618
        for node, port in ((node_a, minor_a), (node_b, minor_b)):
619
          assert node in used, ("Node '%s' of instance '%s' not found"
620
                                " in node list" % (node, instance_name))
621
          if port in used[node]:
622
            duplicates.append((node, port, instance_name, used[node][port]))
623
          else:
624
            used[node][port] = instance_name
625
      if disk.children:
626
        for child in disk.children:
627
          duplicates.extend(_AppendUsedPorts(instance_name, child, used))
628
      return duplicates
629

    
630
    duplicates = []
631
    my_dict = dict((node, {}) for node in self._config_data.nodes)
632
    for instance in self._config_data.instances.itervalues():
633
      for disk in instance.disks:
634
        duplicates.extend(_AppendUsedPorts(instance.name, disk, my_dict))
635
    for (node, minor), instance in self._temporary_drbds.iteritems():
636
      if minor in my_dict[node] and my_dict[node][minor] != instance:
637
        duplicates.append((node, minor, instance, my_dict[node][minor]))
638
      else:
639
        my_dict[node][minor] = instance
640
    return my_dict, duplicates
641

    
642
  @locking.ssynchronized(_config_lock)
643
  def ComputeDRBDMap(self):
644
    """Compute the used DRBD minor/nodes.
645

646
    This is just a wrapper over L{_UnlockedComputeDRBDMap}.
647

648
    @return: dictionary of node_name: dict of minor: instance_name;
649
        the returned dict will have all the nodes in it (even if with
650
        an empty list).
651

652
    """
653
    d_map, duplicates = self._UnlockedComputeDRBDMap()
654
    if duplicates:
655
      raise errors.ConfigurationError("Duplicate DRBD ports detected: %s" %
656
                                      str(duplicates))
657
    return d_map
658

    
659
  @locking.ssynchronized(_config_lock)
660
  def AllocateDRBDMinor(self, nodes, instance):
661
    """Allocate a drbd minor.
662

663
    The free minor will be automatically computed from the existing
664
    devices. A node can be given multiple times in order to allocate
665
    multiple minors. The result is the list of minors, in the same
666
    order as the passed nodes.
667

668
    @type instance: string
669
    @param instance: the instance for which we allocate minors
670

671
    """
672
    assert isinstance(instance, basestring), \
673
           "Invalid argument '%s' passed to AllocateDRBDMinor" % instance
674

    
675
    d_map, duplicates = self._UnlockedComputeDRBDMap()
676
    if duplicates:
677
      raise errors.ConfigurationError("Duplicate DRBD ports detected: %s" %
678
                                      str(duplicates))
679
    result = []
680
    for nname in nodes:
681
      ndata = d_map[nname]
682
      if not ndata:
683
        # no minors used, we can start at 0
684
        result.append(0)
685
        ndata[0] = instance
686
        self._temporary_drbds[(nname, 0)] = instance
687
        continue
688
      keys = ndata.keys()
689
      keys.sort()
690
      ffree = utils.FirstFree(keys)
691
      if ffree is None:
692
        # return the next minor
693
        # TODO: implement high-limit check
694
        minor = keys[-1] + 1
695
      else:
696
        minor = ffree
697
      # double-check minor against current instances
698
      assert minor not in d_map[nname], \
699
             ("Attempt to reuse allocated DRBD minor %d on node %s,"
700
              " already allocated to instance %s" %
701
              (minor, nname, d_map[nname][minor]))
702
      ndata[minor] = instance
703
      # double-check minor against reservation
704
      r_key = (nname, minor)
705
      assert r_key not in self._temporary_drbds, \
706
             ("Attempt to reuse reserved DRBD minor %d on node %s,"
707
              " reserved for instance %s" %
708
              (minor, nname, self._temporary_drbds[r_key]))
709
      self._temporary_drbds[r_key] = instance
710
      result.append(minor)
711
    logging.debug("Request to allocate drbd minors, input: %s, returning %s",
712
                  nodes, result)
713
    return result
714

    
715
  def _UnlockedReleaseDRBDMinors(self, instance):
716
    """Release temporary drbd minors allocated for a given instance.
717

718
    @type instance: string
719
    @param instance: the instance for which temporary minors should be
720
                     released
721

722
    """
723
    assert isinstance(instance, basestring), \
724
           "Invalid argument passed to ReleaseDRBDMinors"
725
    for key, name in self._temporary_drbds.items():
726
      if name == instance:
727
        del self._temporary_drbds[key]
728

    
729
  @locking.ssynchronized(_config_lock)
730
  def ReleaseDRBDMinors(self, instance):
731
    """Release temporary drbd minors allocated for a given instance.
732

733
    This should be called on the error paths, on the success paths
734
    it's automatically called by the ConfigWriter add and update
735
    functions.
736

737
    This function is just a wrapper over L{_UnlockedReleaseDRBDMinors}.
738

739
    @type instance: string
740
    @param instance: the instance for which temporary minors should be
741
                     released
742

743
    """
744
    self._UnlockedReleaseDRBDMinors(instance)
745

    
746
  @locking.ssynchronized(_config_lock, shared=1)
747
  def GetConfigVersion(self):
748
    """Get the configuration version.
749

750
    @return: Config version
751

752
    """
753
    return self._config_data.version
754

    
755
  @locking.ssynchronized(_config_lock, shared=1)
756
  def GetClusterName(self):
757
    """Get cluster name.
758

759
    @return: Cluster name
760

761
    """
762
    return self._config_data.cluster.cluster_name
763

    
764
  @locking.ssynchronized(_config_lock, shared=1)
765
  def GetMasterNode(self):
766
    """Get the hostname of the master node for this cluster.
767

768
    @return: Master hostname
769

770
    """
771
    return self._config_data.cluster.master_node
772

    
773
  @locking.ssynchronized(_config_lock, shared=1)
774
  def GetMasterIP(self):
775
    """Get the IP of the master node for this cluster.
776

777
    @return: Master IP
778

779
    """
780
    return self._config_data.cluster.master_ip
781

    
782
  @locking.ssynchronized(_config_lock, shared=1)
783
  def GetMasterNetdev(self):
784
    """Get the master network device for this cluster.
785

786
    """
787
    return self._config_data.cluster.master_netdev
788

    
789
  @locking.ssynchronized(_config_lock, shared=1)
790
  def GetFileStorageDir(self):
791
    """Get the file storage dir for this cluster.
792

793
    """
794
    return self._config_data.cluster.file_storage_dir
795

    
796
  @locking.ssynchronized(_config_lock, shared=1)
797
  def GetHypervisorType(self):
798
    """Get the hypervisor type for this cluster.
799

800
    """
801
    return self._config_data.cluster.enabled_hypervisors[0]
802

    
803
  @locking.ssynchronized(_config_lock, shared=1)
804
  def GetHostKey(self):
805
    """Return the rsa hostkey from the config.
806

807
    @rtype: string
808
    @return: the rsa hostkey
809

810
    """
811
    return self._config_data.cluster.rsahostkeypub
812

    
813
  @locking.ssynchronized(_config_lock)
814
  def AddInstance(self, instance, ec_id):
815
    """Add an instance to the config.
816

817
    This should be used after creating a new instance.
818

819
    @type instance: L{objects.Instance}
820
    @param instance: the instance object
821

822
    """
823
    if not isinstance(instance, objects.Instance):
824
      raise errors.ProgrammerError("Invalid type passed to AddInstance")
825

    
826
    if instance.disk_template != constants.DT_DISKLESS:
827
      all_lvs = instance.MapLVsByNode()
828
      logging.info("Instance '%s' DISK_LAYOUT: %s", instance.name, all_lvs)
829

    
830
    all_macs = self._AllMACs()
831
    for nic in instance.nics:
832
      if nic.mac in all_macs:
833
        raise errors.ConfigurationError("Cannot add instance %s:"
834
                                        " MAC address '%s' already in use." %
835
                                        (instance.name, nic.mac))
836

    
837
    self._EnsureUUID(instance, ec_id)
838

    
839
    instance.serial_no = 1
840
    instance.ctime = instance.mtime = time.time()
841
    self._config_data.instances[instance.name] = instance
842
    self._config_data.cluster.serial_no += 1
843
    self._UnlockedReleaseDRBDMinors(instance.name)
844
    self._WriteConfig()
845

    
846
  def _EnsureUUID(self, item, ec_id):
847
    """Ensures a given object has a valid UUID.
848

849
    @param item: the instance or node to be checked
850
    @param ec_id: the execution context id for the uuid reservation
851

852
    """
853
    if not item.uuid:
854
      item.uuid = self._GenerateUniqueID(ec_id)
855
    elif item.uuid in self._AllIDs(include_temporary=True):
856
      raise errors.ConfigurationError("Cannot add '%s': UUID %s already"
857
                                      " in use" % (item.name, item.uuid))
858

    
859
  def _SetInstanceStatus(self, instance_name, status):
860
    """Set the instance's status to a given value.
861

862
    """
863
    assert isinstance(status, bool), \
864
           "Invalid status '%s' passed to SetInstanceStatus" % (status,)
865

    
866
    if instance_name not in self._config_data.instances:
867
      raise errors.ConfigurationError("Unknown instance '%s'" %
868
                                      instance_name)
869
    instance = self._config_data.instances[instance_name]
870
    if instance.admin_up != status:
871
      instance.admin_up = status
872
      instance.serial_no += 1
873
      instance.mtime = time.time()
874
      self._WriteConfig()
875

    
876
  @locking.ssynchronized(_config_lock)
877
  def MarkInstanceUp(self, instance_name):
878
    """Mark the instance status to up in the config.
879

880
    """
881
    self._SetInstanceStatus(instance_name, True)
882

    
883
  @locking.ssynchronized(_config_lock)
884
  def RemoveInstance(self, instance_name):
885
    """Remove the instance from the configuration.
886

887
    """
888
    if instance_name not in self._config_data.instances:
889
      raise errors.ConfigurationError("Unknown instance '%s'" % instance_name)
890
    del self._config_data.instances[instance_name]
891
    self._config_data.cluster.serial_no += 1
892
    self._WriteConfig()
893

    
894
  @locking.ssynchronized(_config_lock)
895
  def RenameInstance(self, old_name, new_name):
896
    """Rename an instance.
897

898
    This needs to be done in ConfigWriter and not by RemoveInstance
899
    combined with AddInstance as only we can guarantee an atomic
900
    rename.
901

902
    """
903
    if old_name not in self._config_data.instances:
904
      raise errors.ConfigurationError("Unknown instance '%s'" % old_name)
905
    inst = self._config_data.instances[old_name]
906
    del self._config_data.instances[old_name]
907
    inst.name = new_name
908

    
909
    for disk in inst.disks:
910
      if disk.dev_type == constants.LD_FILE:
911
        # rename the file paths in logical and physical id
912
        file_storage_dir = os.path.dirname(os.path.dirname(disk.logical_id[1]))
913
        disk.physical_id = disk.logical_id = (disk.logical_id[0],
914
                                              utils.PathJoin(file_storage_dir,
915
                                                             inst.name,
916
                                                             disk.iv_name))
917

    
918
    self._config_data.instances[inst.name] = inst
919
    self._WriteConfig()
920

    
921
  @locking.ssynchronized(_config_lock)
922
  def MarkInstanceDown(self, instance_name):
923
    """Mark the status of an instance to down in the configuration.
924

925
    """
926
    self._SetInstanceStatus(instance_name, False)
927

    
928
  def _UnlockedGetInstanceList(self):
929
    """Get the list of instances.
930

931
    This function is for internal use, when the config lock is already held.
932

933
    """
934
    return self._config_data.instances.keys()
935

    
936
  @locking.ssynchronized(_config_lock, shared=1)
937
  def GetInstanceList(self):
938
    """Get the list of instances.
939

940
    @return: array of instances, ex. ['instance2.example.com',
941
        'instance1.example.com']
942

943
    """
944
    return self._UnlockedGetInstanceList()
945

    
946
  @locking.ssynchronized(_config_lock, shared=1)
947
  def ExpandInstanceName(self, short_name):
948
    """Attempt to expand an incomplete instance name.
949

950
    """
951
    return utils.MatchNameComponent(short_name,
952
                                    self._config_data.instances.keys(),
953
                                    case_sensitive=False)
954

    
955
  def _UnlockedGetInstanceInfo(self, instance_name):
956
    """Returns information about an instance.
957

958
    This function is for internal use, when the config lock is already held.
959

960
    """
961
    if instance_name not in self._config_data.instances:
962
      return None
963

    
964
    return self._config_data.instances[instance_name]
965

    
966
  @locking.ssynchronized(_config_lock, shared=1)
967
  def GetInstanceInfo(self, instance_name):
968
    """Returns information about an instance.
969

970
    It takes the information from the configuration file. Other information of
971
    an instance are taken from the live systems.
972

973
    @param instance_name: name of the instance, e.g.
974
        I{instance1.example.com}
975

976
    @rtype: L{objects.Instance}
977
    @return: the instance object
978

979
    """
980
    return self._UnlockedGetInstanceInfo(instance_name)
981

    
982
  @locking.ssynchronized(_config_lock, shared=1)
983
  def GetAllInstancesInfo(self):
984
    """Get the configuration of all instances.
985

986
    @rtype: dict
987
    @return: dict of (instance, instance_info), where instance_info is what
988
              would GetInstanceInfo return for the node
989

990
    """
991
    my_dict = dict([(instance, self._UnlockedGetInstanceInfo(instance))
992
                    for instance in self._UnlockedGetInstanceList()])
993
    return my_dict
994

    
995
  @locking.ssynchronized(_config_lock)
996
  def AddNode(self, node, ec_id):
997
    """Add a node to the configuration.
998

999
    @type node: L{objects.Node}
1000
    @param node: a Node instance
1001

1002
    """
1003
    logging.info("Adding node %s to configuration", node.name)
1004

    
1005
    self._EnsureUUID(node, ec_id)
1006

    
1007
    node.serial_no = 1
1008
    node.ctime = node.mtime = time.time()
1009
    self._config_data.nodes[node.name] = node
1010
    self._config_data.cluster.serial_no += 1
1011
    self._WriteConfig()
1012

    
1013
  @locking.ssynchronized(_config_lock)
1014
  def RemoveNode(self, node_name):
1015
    """Remove a node from the configuration.
1016

1017
    """
1018
    logging.info("Removing node %s from configuration", node_name)
1019

    
1020
    if node_name not in self._config_data.nodes:
1021
      raise errors.ConfigurationError("Unknown node '%s'" % node_name)
1022

    
1023
    del self._config_data.nodes[node_name]
1024
    self._config_data.cluster.serial_no += 1
1025
    self._WriteConfig()
1026

    
1027
  @locking.ssynchronized(_config_lock, shared=1)
1028
  def ExpandNodeName(self, short_name):
1029
    """Attempt to expand an incomplete instance name.
1030

1031
    """
1032
    return utils.MatchNameComponent(short_name,
1033
                                    self._config_data.nodes.keys(),
1034
                                    case_sensitive=False)
1035

    
1036
  def _UnlockedGetNodeInfo(self, node_name):
1037
    """Get the configuration of a node, as stored in the config.
1038

1039
    This function is for internal use, when the config lock is already
1040
    held.
1041

1042
    @param node_name: the node name, e.g. I{node1.example.com}
1043

1044
    @rtype: L{objects.Node}
1045
    @return: the node object
1046

1047
    """
1048
    if node_name not in self._config_data.nodes:
1049
      return None
1050

    
1051
    return self._config_data.nodes[node_name]
1052

    
1053
  @locking.ssynchronized(_config_lock, shared=1)
1054
  def GetNodeInfo(self, node_name):
1055
    """Get the configuration of a node, as stored in the config.
1056

1057
    This is just a locked wrapper over L{_UnlockedGetNodeInfo}.
1058

1059
    @param node_name: the node name, e.g. I{node1.example.com}
1060

1061
    @rtype: L{objects.Node}
1062
    @return: the node object
1063

1064
    """
1065
    return self._UnlockedGetNodeInfo(node_name)
1066

    
1067
  def _UnlockedGetNodeList(self):
1068
    """Return the list of nodes which are in the configuration.
1069

1070
    This function is for internal use, when the config lock is already
1071
    held.
1072

1073
    @rtype: list
1074

1075
    """
1076
    return self._config_data.nodes.keys()
1077

    
1078
  @locking.ssynchronized(_config_lock, shared=1)
1079
  def GetNodeList(self):
1080
    """Return the list of nodes which are in the configuration.
1081

1082
    """
1083
    return self._UnlockedGetNodeList()
1084

    
1085
  def _UnlockedGetOnlineNodeList(self):
1086
    """Return the list of nodes which are online.
1087

1088
    """
1089
    all_nodes = [self._UnlockedGetNodeInfo(node)
1090
                 for node in self._UnlockedGetNodeList()]
1091
    return [node.name for node in all_nodes if not node.offline]
1092

    
1093
  @locking.ssynchronized(_config_lock, shared=1)
1094
  def GetOnlineNodeList(self):
1095
    """Return the list of nodes which are online.
1096

1097
    """
1098
    return self._UnlockedGetOnlineNodeList()
1099

    
1100
  @locking.ssynchronized(_config_lock, shared=1)
1101
  def GetAllNodesInfo(self):
1102
    """Get the configuration of all nodes.
1103

1104
    @rtype: dict
1105
    @return: dict of (node, node_info), where node_info is what
1106
              would GetNodeInfo return for the node
1107

1108
    """
1109
    my_dict = dict([(node, self._UnlockedGetNodeInfo(node))
1110
                    for node in self._UnlockedGetNodeList()])
1111
    return my_dict
1112

    
1113
  def _UnlockedGetMasterCandidateStats(self, exceptions=None):
1114
    """Get the number of current and maximum desired and possible candidates.
1115

1116
    @type exceptions: list
1117
    @param exceptions: if passed, list of nodes that should be ignored
1118
    @rtype: tuple
1119
    @return: tuple of (current, desired and possible, possible)
1120

1121
    """
1122
    mc_now = mc_should = mc_max = 0
1123
    for node in self._config_data.nodes.values():
1124
      if exceptions and node.name in exceptions:
1125
        continue
1126
      if not (node.offline or node.drained):
1127
        mc_max += 1
1128
      if node.master_candidate:
1129
        mc_now += 1
1130
    mc_should = min(mc_max, self._config_data.cluster.candidate_pool_size)
1131
    return (mc_now, mc_should, mc_max)
1132

    
1133
  @locking.ssynchronized(_config_lock, shared=1)
1134
  def GetMasterCandidateStats(self, exceptions=None):
1135
    """Get the number of current and maximum possible candidates.
1136

1137
    This is just a wrapper over L{_UnlockedGetMasterCandidateStats}.
1138

1139
    @type exceptions: list
1140
    @param exceptions: if passed, list of nodes that should be ignored
1141
    @rtype: tuple
1142
    @return: tuple of (current, max)
1143

1144
    """
1145
    return self._UnlockedGetMasterCandidateStats(exceptions)
1146

    
1147
  @locking.ssynchronized(_config_lock)
1148
  def MaintainCandidatePool(self, exceptions):
1149
    """Try to grow the candidate pool to the desired size.
1150

1151
    @type exceptions: list
1152
    @param exceptions: if passed, list of nodes that should be ignored
1153
    @rtype: list
1154
    @return: list with the adjusted nodes (L{objects.Node} instances)
1155

1156
    """
1157
    mc_now, mc_max, _ = self._UnlockedGetMasterCandidateStats(exceptions)
1158
    mod_list = []
1159
    if mc_now < mc_max:
1160
      node_list = self._config_data.nodes.keys()
1161
      random.shuffle(node_list)
1162
      for name in node_list:
1163
        if mc_now >= mc_max:
1164
          break
1165
        node = self._config_data.nodes[name]
1166
        if (node.master_candidate or node.offline or node.drained or
1167
            node.name in exceptions):
1168
          continue
1169
        mod_list.append(node)
1170
        node.master_candidate = True
1171
        node.serial_no += 1
1172
        mc_now += 1
1173
      if mc_now != mc_max:
1174
        # this should not happen
1175
        logging.warning("Warning: MaintainCandidatePool didn't manage to"
1176
                        " fill the candidate pool (%d/%d)", mc_now, mc_max)
1177
      if mod_list:
1178
        self._config_data.cluster.serial_no += 1
1179
        self._WriteConfig()
1180

    
1181
    return mod_list
1182

    
1183
  def _BumpSerialNo(self):
1184
    """Bump up the serial number of the config.
1185

1186
    """
1187
    self._config_data.serial_no += 1
1188
    self._config_data.mtime = time.time()
1189

    
1190
  def _AllUUIDObjects(self):
1191
    """Returns all objects with uuid attributes.
1192

1193
    """
1194
    return (self._config_data.instances.values() +
1195
            self._config_data.nodes.values() +
1196
            [self._config_data.cluster])
1197

    
1198
  def _OpenConfig(self):
1199
    """Read the config data from disk.
1200

1201
    """
1202
    raw_data = utils.ReadFile(self._cfg_file)
1203

    
1204
    try:
1205
      data = objects.ConfigData.FromDict(serializer.Load(raw_data))
1206
    except Exception, err:
1207
      raise errors.ConfigurationError(err)
1208

    
1209
    # Make sure the configuration has the right version
1210
    _ValidateConfig(data)
1211

    
1212
    if (not hasattr(data, 'cluster') or
1213
        not hasattr(data.cluster, 'rsahostkeypub')):
1214
      raise errors.ConfigurationError("Incomplete configuration"
1215
                                      " (missing cluster.rsahostkeypub)")
1216

    
1217
    # Upgrade configuration if needed
1218
    data.UpgradeConfig()
1219

    
1220
    self._config_data = data
1221
    # reset the last serial as -1 so that the next write will cause
1222
    # ssconf update
1223
    self._last_cluster_serial = -1
1224

    
1225
    # And finally run our (custom) config upgrade sequence
1226
    self._UpgradeConfig()
1227

    
1228
  def _UpgradeConfig(self):
1229
    """Run upgrade steps that cannot be done purely in the objects.
1230

1231
    This is because some data elements need uniqueness across the
1232
    whole configuration, etc.
1233

1234
    @warning: this function will call L{_WriteConfig()}, so it needs
1235
        to either be called with the lock held or from a safe place
1236
        (the constructor)
1237

1238
    """
1239
    modified = False
1240
    for item in self._AllUUIDObjects():
1241
      if item.uuid is None:
1242
        item.uuid = self._GenerateUniqueID(_UPGRADE_CONFIG_JID)
1243
        modified = True
1244
    if modified:
1245
      self._WriteConfig()
1246
      # This is ok even if it acquires the internal lock, as _UpgradeConfig is
1247
      # only called at config init time, without the lock held
1248
      self.DropECReservations(_UPGRADE_CONFIG_JID)
1249

    
1250
  def _DistributeConfig(self, feedback_fn):
1251
    """Distribute the configuration to the other nodes.
1252

1253
    Currently, this only copies the configuration file. In the future,
1254
    it could be used to encapsulate the 2/3-phase update mechanism.
1255

1256
    """
1257
    if self._offline:
1258
      return True
1259

    
1260
    bad = False
1261

    
1262
    node_list = []
1263
    addr_list = []
1264
    myhostname = self._my_hostname
1265
    # we can skip checking whether _UnlockedGetNodeInfo returns None
1266
    # since the node list comes from _UnlocketGetNodeList, and we are
1267
    # called with the lock held, so no modifications should take place
1268
    # in between
1269
    for node_name in self._UnlockedGetNodeList():
1270
      if node_name == myhostname:
1271
        continue
1272
      node_info = self._UnlockedGetNodeInfo(node_name)
1273
      if not node_info.master_candidate:
1274
        continue
1275
      node_list.append(node_info.name)
1276
      addr_list.append(node_info.primary_ip)
1277

    
1278
    result = rpc.RpcRunner.call_upload_file(node_list, self._cfg_file,
1279
                                            address_list=addr_list)
1280
    for to_node, to_result in result.items():
1281
      msg = to_result.fail_msg
1282
      if msg:
1283
        msg = ("Copy of file %s to node %s failed: %s" %
1284
               (self._cfg_file, to_node, msg))
1285
        logging.error(msg)
1286

    
1287
        if feedback_fn:
1288
          feedback_fn(msg)
1289

    
1290
        bad = True
1291

    
1292
    return not bad
1293

    
1294
  def _WriteConfig(self, destination=None, feedback_fn=None):
1295
    """Write the configuration data to persistent storage.
1296

1297
    """
1298
    assert feedback_fn is None or callable(feedback_fn)
1299

    
1300
    # Warn on config errors, but don't abort the save - the
1301
    # configuration has already been modified, and we can't revert;
1302
    # the best we can do is to warn the user and save as is, leaving
1303
    # recovery to the user
1304
    config_errors = self._UnlockedVerifyConfig()
1305
    if config_errors:
1306
      errmsg = ("Configuration data is not consistent: %s" %
1307
                (utils.CommaJoin(config_errors)))
1308
      logging.critical(errmsg)
1309
      if feedback_fn:
1310
        feedback_fn(errmsg)
1311

    
1312
    if destination is None:
1313
      destination = self._cfg_file
1314
    self._BumpSerialNo()
1315
    txt = serializer.Dump(self._config_data.ToDict())
1316

    
1317
    utils.WriteFile(destination, data=txt)
1318

    
1319
    self.write_count += 1
1320

    
1321
    # and redistribute the config file to master candidates
1322
    self._DistributeConfig(feedback_fn)
1323

    
1324
    # Write ssconf files on all nodes (including locally)
1325
    if self._last_cluster_serial < self._config_data.cluster.serial_no:
1326
      if not self._offline:
1327
        result = rpc.RpcRunner.call_write_ssconf_files(
1328
          self._UnlockedGetOnlineNodeList(),
1329
          self._UnlockedGetSsconfValues())
1330

    
1331
        for nname, nresu in result.items():
1332
          msg = nresu.fail_msg
1333
          if msg:
1334
            errmsg = ("Error while uploading ssconf files to"
1335
                      " node %s: %s" % (nname, msg))
1336
            logging.warning(errmsg)
1337

    
1338
            if feedback_fn:
1339
              feedback_fn(errmsg)
1340

    
1341
      self._last_cluster_serial = self._config_data.cluster.serial_no
1342

    
1343
  def _UnlockedGetSsconfValues(self):
1344
    """Return the values needed by ssconf.
1345

1346
    @rtype: dict
1347
    @return: a dictionary with keys the ssconf names and values their
1348
        associated value
1349

1350
    """
1351
    fn = "\n".join
1352
    instance_names = utils.NiceSort(self._UnlockedGetInstanceList())
1353
    node_names = utils.NiceSort(self._UnlockedGetNodeList())
1354
    node_info = [self._UnlockedGetNodeInfo(name) for name in node_names]
1355
    node_pri_ips = ["%s %s" % (ninfo.name, ninfo.primary_ip)
1356
                    for ninfo in node_info]
1357
    node_snd_ips = ["%s %s" % (ninfo.name, ninfo.secondary_ip)
1358
                    for ninfo in node_info]
1359

    
1360
    instance_data = fn(instance_names)
1361
    off_data = fn(node.name for node in node_info if node.offline)
1362
    on_data = fn(node.name for node in node_info if not node.offline)
1363
    mc_data = fn(node.name for node in node_info if node.master_candidate)
1364
    mc_ips_data = fn(node.primary_ip for node in node_info
1365
                     if node.master_candidate)
1366
    node_data = fn(node_names)
1367
    node_pri_ips_data = fn(node_pri_ips)
1368
    node_snd_ips_data = fn(node_snd_ips)
1369

    
1370
    cluster = self._config_data.cluster
1371
    cluster_tags = fn(cluster.GetTags())
1372

    
1373
    hypervisor_list = fn(cluster.enabled_hypervisors)
1374

    
1375
    return {
1376
      constants.SS_CLUSTER_NAME: cluster.cluster_name,
1377
      constants.SS_CLUSTER_TAGS: cluster_tags,
1378
      constants.SS_FILE_STORAGE_DIR: cluster.file_storage_dir,
1379
      constants.SS_MASTER_CANDIDATES: mc_data,
1380
      constants.SS_MASTER_CANDIDATES_IPS: mc_ips_data,
1381
      constants.SS_MASTER_IP: cluster.master_ip,
1382
      constants.SS_MASTER_NETDEV: cluster.master_netdev,
1383
      constants.SS_MASTER_NODE: cluster.master_node,
1384
      constants.SS_NODE_LIST: node_data,
1385
      constants.SS_NODE_PRIMARY_IPS: node_pri_ips_data,
1386
      constants.SS_NODE_SECONDARY_IPS: node_snd_ips_data,
1387
      constants.SS_OFFLINE_NODES: off_data,
1388
      constants.SS_ONLINE_NODES: on_data,
1389
      constants.SS_INSTANCE_LIST: instance_data,
1390
      constants.SS_RELEASE_VERSION: constants.RELEASE_VERSION,
1391
      constants.SS_HYPERVISOR_LIST: hypervisor_list,
1392
      }
1393

    
1394
  @locking.ssynchronized(_config_lock, shared=1)
1395
  def GetVGName(self):
1396
    """Return the volume group name.
1397

1398
    """
1399
    return self._config_data.cluster.volume_group_name
1400

    
1401
  @locking.ssynchronized(_config_lock)
1402
  def SetVGName(self, vg_name):
1403
    """Set the volume group name.
1404

1405
    """
1406
    self._config_data.cluster.volume_group_name = vg_name
1407
    self._config_data.cluster.serial_no += 1
1408
    self._WriteConfig()
1409

    
1410
  @locking.ssynchronized(_config_lock, shared=1)
1411
  def GetMACPrefix(self):
1412
    """Return the mac prefix.
1413

1414
    """
1415
    return self._config_data.cluster.mac_prefix
1416

    
1417
  @locking.ssynchronized(_config_lock, shared=1)
1418
  def GetClusterInfo(self):
1419
    """Returns information about the cluster
1420

1421
    @rtype: L{objects.Cluster}
1422
    @return: the cluster object
1423

1424
    """
1425
    return self._config_data.cluster
1426

    
1427
  @locking.ssynchronized(_config_lock)
1428
  def Update(self, target, feedback_fn):
1429
    """Notify function to be called after updates.
1430

1431
    This function must be called when an object (as returned by
1432
    GetInstanceInfo, GetNodeInfo, GetCluster) has been updated and the
1433
    caller wants the modifications saved to the backing store. Note
1434
    that all modified objects will be saved, but the target argument
1435
    is the one the caller wants to ensure that it's saved.
1436

1437
    @param target: an instance of either L{objects.Cluster},
1438
        L{objects.Node} or L{objects.Instance} which is existing in
1439
        the cluster
1440
    @param feedback_fn: Callable feedback function
1441

1442
    """
1443
    if self._config_data is None:
1444
      raise errors.ProgrammerError("Configuration file not read,"
1445
                                   " cannot save.")
1446
    update_serial = False
1447
    if isinstance(target, objects.Cluster):
1448
      test = target == self._config_data.cluster
1449
    elif isinstance(target, objects.Node):
1450
      test = target in self._config_data.nodes.values()
1451
      update_serial = True
1452
    elif isinstance(target, objects.Instance):
1453
      test = target in self._config_data.instances.values()
1454
    else:
1455
      raise errors.ProgrammerError("Invalid object type (%s) passed to"
1456
                                   " ConfigWriter.Update" % type(target))
1457
    if not test:
1458
      raise errors.ConfigurationError("Configuration updated since object"
1459
                                      " has been read or unknown object")
1460
    target.serial_no += 1
1461
    target.mtime = now = time.time()
1462

    
1463
    if update_serial:
1464
      # for node updates, we need to increase the cluster serial too
1465
      self._config_data.cluster.serial_no += 1
1466
      self._config_data.cluster.mtime = now
1467

    
1468
    if isinstance(target, objects.Instance):
1469
      self._UnlockedReleaseDRBDMinors(target.name)
1470

    
1471
    self._WriteConfig(feedback_fn=feedback_fn)
1472

    
1473
  @locking.ssynchronized(_config_lock)
1474
  def DropECReservations(self, ec_id):
1475
    """Drop per-execution-context reservations
1476

1477
    """
1478
    for rm in self._all_rms:
1479
      rm.DropECReservations(ec_id)