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#
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#
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# Copyright (C) 2006, 2007, 2008 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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"""Functions to bootstrap a new cluster.
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"""
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import os
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import os.path
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import re
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import logging
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import time
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from ganeti import rpc
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from ganeti import ssh
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from ganeti import utils
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from ganeti import errors
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from ganeti import config
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from ganeti import constants
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from ganeti import objects
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from ganeti import ssconf
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from ganeti import serializer
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from ganeti import hypervisor
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def _InitSSHSetup():
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  """Setup the SSH configuration for the cluster.
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  This generates a dsa keypair for root, adds the pub key to the
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  permitted hosts and adds the hostkey to its own known hosts.
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  """
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  priv_key, pub_key, auth_keys = ssh.GetUserFiles(constants.GANETI_RUNAS)
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  for name in priv_key, pub_key:
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    if os.path.exists(name):
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      utils.CreateBackup(name)
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    utils.RemoveFile(name)
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  result = utils.RunCmd(["ssh-keygen", "-t", "dsa",
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                         "-f", priv_key,
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                         "-q", "-N", ""])
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  if result.failed:
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    raise errors.OpExecError("Could not generate ssh keypair, error %s" %
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                             result.output)
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  utils.AddAuthorizedKey(auth_keys, utils.ReadFile(pub_key))
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67

    
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def GenerateHmacKey(file_name):
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  """Writes a new HMAC key.
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  @type file_name: str
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  @param file_name: Path to output file
73

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  """
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  utils.WriteFile(file_name, data="%s\n" % utils.GenerateSecret(), mode=0400,
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                  backup=True)
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78

    
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def GenerateClusterCrypto(new_cluster_cert, new_rapi_cert, new_confd_hmac_key,
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                          new_cds, rapi_cert_pem=None, cds=None):
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  """Updates the cluster certificates, keys and secrets.
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83
  @type new_cluster_cert: bool
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  @param new_cluster_cert: Whether to generate a new cluster certificate
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  @type new_rapi_cert: bool
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  @param new_rapi_cert: Whether to generate a new RAPI certificate
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  @type new_confd_hmac_key: bool
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  @param new_confd_hmac_key: Whether to generate a new HMAC key
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  @type new_cds: bool
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  @param new_cds: Whether to generate a new cluster domain secret
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  @type rapi_cert_pem: string
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  @param rapi_cert_pem: New RAPI certificate in PEM format
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  @type cds: string
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  @param cds: New cluster domain secret
95

96
  """
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  # noded SSL certificate
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  cluster_cert_exists = os.path.exists(constants.NODED_CERT_FILE)
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  if new_cluster_cert or not cluster_cert_exists:
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    if cluster_cert_exists:
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      utils.CreateBackup(constants.NODED_CERT_FILE)
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103
    logging.debug("Generating new cluster certificate at %s",
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                  constants.NODED_CERT_FILE)
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    utils.GenerateSelfSignedSslCert(constants.NODED_CERT_FILE)
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107
  # confd HMAC key
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  if new_confd_hmac_key or not os.path.exists(constants.CONFD_HMAC_KEY):
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    logging.debug("Writing new confd HMAC key to %s", constants.CONFD_HMAC_KEY)
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    GenerateHmacKey(constants.CONFD_HMAC_KEY)
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112
  # RAPI
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  rapi_cert_exists = os.path.exists(constants.RAPI_CERT_FILE)
114

    
115
  if rapi_cert_pem:
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    # Assume rapi_pem contains a valid PEM-formatted certificate and key
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    logging.debug("Writing RAPI certificate at %s",
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                  constants.RAPI_CERT_FILE)
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    utils.WriteFile(constants.RAPI_CERT_FILE, data=rapi_cert_pem, backup=True)
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  elif new_rapi_cert or not rapi_cert_exists:
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    if rapi_cert_exists:
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      utils.CreateBackup(constants.RAPI_CERT_FILE)
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    logging.debug("Generating new RAPI certificate at %s",
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                  constants.RAPI_CERT_FILE)
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    utils.GenerateSelfSignedSslCert(constants.RAPI_CERT_FILE)
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  # Cluster domain secret
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  if cds:
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    logging.debug("Writing cluster domain secret to %s",
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                  constants.CLUSTER_DOMAIN_SECRET_FILE)
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    utils.WriteFile(constants.CLUSTER_DOMAIN_SECRET_FILE,
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                    data=cds, backup=True)
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136
  elif new_cds or not os.path.exists(constants.CLUSTER_DOMAIN_SECRET_FILE):
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    logging.debug("Generating new cluster domain secret at %s",
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                  constants.CLUSTER_DOMAIN_SECRET_FILE)
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    GenerateHmacKey(constants.CLUSTER_DOMAIN_SECRET_FILE)
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141

    
142
def _InitGanetiServerSetup(master_name):
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  """Setup the necessary configuration for the initial node daemon.
144

145
  This creates the nodepass file containing the shared password for
146
  the cluster and also generates the SSL certificate.
147

148
  """
149
  # Generate cluster secrets
150
  GenerateClusterCrypto(True, False, False, False)
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152
  result = utils.RunCmd([constants.DAEMON_UTIL, "start", constants.NODED])
153
  if result.failed:
154
    raise errors.OpExecError("Could not start the node daemon, command %s"
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                             " had exitcode %s and error %s" %
156
                             (result.cmd, result.exit_code, result.output))
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158
  _WaitForNodeDaemon(master_name)
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160

    
161
def _WaitForNodeDaemon(node_name):
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  """Wait for node daemon to become responsive.
163

164
  """
165
  def _CheckNodeDaemon():
166
    result = rpc.RpcRunner.call_version([node_name])[node_name]
167
    if result.fail_msg:
168
      raise utils.RetryAgain()
169

    
170
  try:
171
    utils.Retry(_CheckNodeDaemon, 1.0, 10.0)
172
  except utils.RetryTimeout:
173
    raise errors.OpExecError("Node daemon on %s didn't answer queries within"
174
                             " 10 seconds" % node_name)
175

    
176

    
177
def InitCluster(cluster_name, mac_prefix,
178
                master_netdev, file_storage_dir, candidate_pool_size,
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                secondary_ip=None, vg_name=None, beparams=None,
180
                nicparams=None, hvparams=None, enabled_hypervisors=None,
181
                modify_etc_hosts=True, modify_ssh_setup=True):
182
  """Initialise the cluster.
183

184
  @type candidate_pool_size: int
185
  @param candidate_pool_size: master candidate pool size
186

187
  """
188
  # TODO: complete the docstring
189
  if config.ConfigWriter.IsCluster():
190
    raise errors.OpPrereqError("Cluster is already initialised",
191
                               errors.ECODE_STATE)
192

    
193
  if not enabled_hypervisors:
194
    raise errors.OpPrereqError("Enabled hypervisors list must contain at"
195
                               " least one member", errors.ECODE_INVAL)
196
  invalid_hvs = set(enabled_hypervisors) - constants.HYPER_TYPES
197
  if invalid_hvs:
198
    raise errors.OpPrereqError("Enabled hypervisors contains invalid"
199
                               " entries: %s" % invalid_hvs,
200
                               errors.ECODE_INVAL)
201

    
202
  hostname = utils.GetHostInfo()
203

    
204
  if hostname.ip.startswith("127."):
205
    raise errors.OpPrereqError("This host's IP resolves to the private"
206
                               " range (%s). Please fix DNS or %s." %
207
                               (hostname.ip, constants.ETC_HOSTS),
208
                               errors.ECODE_ENVIRON)
209

    
210
  if not utils.OwnIpAddress(hostname.ip):
211
    raise errors.OpPrereqError("Inconsistency: this host's name resolves"
212
                               " to %s,\nbut this ip address does not"
213
                               " belong to this host. Aborting." %
214
                               hostname.ip, errors.ECODE_ENVIRON)
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216
  clustername = utils.GetHostInfo(utils.HostInfo.NormalizeName(cluster_name))
217

    
218
  if utils.TcpPing(clustername.ip, constants.DEFAULT_NODED_PORT,
219
                   timeout=5):
220
    raise errors.OpPrereqError("Cluster IP already active. Aborting.",
221
                               errors.ECODE_NOTUNIQUE)
222

    
223
  if secondary_ip:
224
    if not utils.IsValidIP(secondary_ip):
225
      raise errors.OpPrereqError("Invalid secondary ip given",
226
                                 errors.ECODE_INVAL)
227
    if (secondary_ip != hostname.ip and
228
        not utils.OwnIpAddress(secondary_ip)):
229
      raise errors.OpPrereqError("You gave %s as secondary IP,"
230
                                 " but it does not belong to this host." %
231
                                 secondary_ip, errors.ECODE_ENVIRON)
232
  else:
233
    secondary_ip = hostname.ip
234

    
235
  if vg_name is not None:
236
    # Check if volume group is valid
237
    vgstatus = utils.CheckVolumeGroupSize(utils.ListVolumeGroups(), vg_name,
238
                                          constants.MIN_VG_SIZE)
239
    if vgstatus:
240
      raise errors.OpPrereqError("Error: %s\nspecify --no-lvm-storage if"
241
                                 " you are not using lvm" % vgstatus,
242
                                 errors.ECODE_INVAL)
243

    
244
  file_storage_dir = os.path.normpath(file_storage_dir)
245

    
246
  if not os.path.isabs(file_storage_dir):
247
    raise errors.OpPrereqError("The file storage directory you passed is"
248
                               " not an absolute path.", errors.ECODE_INVAL)
249

    
250
  if not os.path.exists(file_storage_dir):
251
    try:
252
      os.makedirs(file_storage_dir, 0750)
253
    except OSError, err:
254
      raise errors.OpPrereqError("Cannot create file storage directory"
255
                                 " '%s': %s" % (file_storage_dir, err),
256
                                 errors.ECODE_ENVIRON)
257

    
258
  if not os.path.isdir(file_storage_dir):
259
    raise errors.OpPrereqError("The file storage directory '%s' is not"
260
                               " a directory." % file_storage_dir,
261
                               errors.ECODE_ENVIRON)
262

    
263
  if not re.match("^[0-9a-z]{2}:[0-9a-z]{2}:[0-9a-z]{2}$", mac_prefix):
264
    raise errors.OpPrereqError("Invalid mac prefix given '%s'" % mac_prefix,
265
                               errors.ECODE_INVAL)
266

    
267
  result = utils.RunCmd(["ip", "link", "show", "dev", master_netdev])
268
  if result.failed:
269
    raise errors.OpPrereqError("Invalid master netdev given (%s): '%s'" %
270
                               (master_netdev,
271
                                result.output.strip()), errors.ECODE_INVAL)
272

    
273
  dirs = [(constants.RUN_GANETI_DIR, constants.RUN_DIRS_MODE)]
274
  utils.EnsureDirs(dirs)
275

    
276
  utils.ForceDictType(beparams, constants.BES_PARAMETER_TYPES)
277
  utils.ForceDictType(nicparams, constants.NICS_PARAMETER_TYPES)
278
  objects.NIC.CheckParameterSyntax(nicparams)
279

    
280
  # hvparams is a mapping of hypervisor->hvparams dict
281
  for hv_name, hv_params in hvparams.iteritems():
282
    utils.ForceDictType(hv_params, constants.HVS_PARAMETER_TYPES)
283
    hv_class = hypervisor.GetHypervisor(hv_name)
284
    hv_class.CheckParameterSyntax(hv_params)
285

    
286
  # set up the inter-node password and certificate
287
  _InitGanetiServerSetup(hostname.name)
288

    
289
  # set up ssh config and /etc/hosts
290
  sshline = utils.ReadFile(constants.SSH_HOST_RSA_PUB)
291
  sshkey = sshline.split(" ")[1]
292

    
293
  if modify_etc_hosts:
294
    utils.AddHostToEtcHosts(hostname.name)
295

    
296
  if modify_ssh_setup:
297
    _InitSSHSetup()
298

    
299
  now = time.time()
300

    
301
  # init of cluster config file
302
  cluster_config = objects.Cluster(
303
    serial_no=1,
304
    rsahostkeypub=sshkey,
305
    highest_used_port=(constants.FIRST_DRBD_PORT - 1),
306
    mac_prefix=mac_prefix,
307
    volume_group_name=vg_name,
308
    tcpudp_port_pool=set(),
309
    master_node=hostname.name,
310
    master_ip=clustername.ip,
311
    master_netdev=master_netdev,
312
    cluster_name=clustername.name,
313
    file_storage_dir=file_storage_dir,
314
    enabled_hypervisors=enabled_hypervisors,
315
    beparams={constants.PP_DEFAULT: beparams},
316
    nicparams={constants.PP_DEFAULT: nicparams},
317
    hvparams=hvparams,
318
    candidate_pool_size=candidate_pool_size,
319
    modify_etc_hosts=modify_etc_hosts,
320
    modify_ssh_setup=modify_ssh_setup,
321
    ctime=now,
322
    mtime=now,
323
    uuid=utils.NewUUID(),
324
    )
325
  master_node_config = objects.Node(name=hostname.name,
326
                                    primary_ip=hostname.ip,
327
                                    secondary_ip=secondary_ip,
328
                                    serial_no=1,
329
                                    master_candidate=True,
330
                                    offline=False, drained=False,
331
                                    )
332
  InitConfig(constants.CONFIG_VERSION, cluster_config, master_node_config)
333
  cfg = config.ConfigWriter()
334
  ssh.WriteKnownHostsFile(cfg, constants.SSH_KNOWN_HOSTS_FILE)
335
  cfg.Update(cfg.GetClusterInfo(), logging.error)
336

    
337
  # start the master ip
338
  # TODO: Review rpc call from bootstrap
339
  # TODO: Warn on failed start master
340
  rpc.RpcRunner.call_node_start_master(hostname.name, True, False)
341

    
342

    
343
def InitConfig(version, cluster_config, master_node_config,
344
               cfg_file=constants.CLUSTER_CONF_FILE):
345
  """Create the initial cluster configuration.
346

347
  It will contain the current node, which will also be the master
348
  node, and no instances.
349

350
  @type version: int
351
  @param version: configuration version
352
  @type cluster_config: L{objects.Cluster}
353
  @param cluster_config: cluster configuration
354
  @type master_node_config: L{objects.Node}
355
  @param master_node_config: master node configuration
356
  @type cfg_file: string
357
  @param cfg_file: configuration file path
358

359
  """
360
  nodes = {
361
    master_node_config.name: master_node_config,
362
    }
363

    
364
  now = time.time()
365
  config_data = objects.ConfigData(version=version,
366
                                   cluster=cluster_config,
367
                                   nodes=nodes,
368
                                   instances={},
369
                                   serial_no=1,
370
                                   ctime=now, mtime=now)
371
  utils.WriteFile(cfg_file,
372
                  data=serializer.Dump(config_data.ToDict()),
373
                  mode=0600)
374

    
375

    
376
def FinalizeClusterDestroy(master):
377
  """Execute the last steps of cluster destroy
378

379
  This function shuts down all the daemons, completing the destroy
380
  begun in cmdlib.LUDestroyOpcode.
381

382
  """
383
  cfg = config.ConfigWriter()
384
  modify_ssh_setup = cfg.GetClusterInfo().modify_ssh_setup
385
  result = rpc.RpcRunner.call_node_stop_master(master, True)
386
  msg = result.fail_msg
387
  if msg:
388
    logging.warning("Could not disable the master role: %s", msg)
389
  result = rpc.RpcRunner.call_node_leave_cluster(master, modify_ssh_setup)
390
  msg = result.fail_msg
391
  if msg:
392
    logging.warning("Could not shutdown the node daemon and cleanup"
393
                    " the node: %s", msg)
394

    
395

    
396
def SetupNodeDaemon(cluster_name, node, ssh_key_check):
397
  """Add a node to the cluster.
398

399
  This function must be called before the actual opcode, and will ssh
400
  to the remote node, copy the needed files, and start ganeti-noded,
401
  allowing the master to do the rest via normal rpc calls.
402

403
  @param cluster_name: the cluster name
404
  @param node: the name of the new node
405
  @param ssh_key_check: whether to do a strict key check
406

407
  """
408
  sshrunner = ssh.SshRunner(cluster_name)
409

    
410
  noded_cert = utils.ReadFile(constants.NODED_CERT_FILE)
411
  rapi_cert = utils.ReadFile(constants.RAPI_CERT_FILE)
412
  confd_hmac_key = utils.ReadFile(constants.CONFD_HMAC_KEY)
413

    
414
  # in the base64 pem encoding, neither '!' nor '.' are valid chars,
415
  # so we use this to detect an invalid certificate; as long as the
416
  # cert doesn't contain this, the here-document will be correctly
417
  # parsed by the shell sequence below. HMAC keys are hexadecimal strings,
418
  # so the same restrictions apply.
419
  for content in (noded_cert, rapi_cert, confd_hmac_key):
420
    if re.search('^!EOF\.', content, re.MULTILINE):
421
      raise errors.OpExecError("invalid SSL certificate or HMAC key")
422

    
423
  if not noded_cert.endswith("\n"):
424
    noded_cert += "\n"
425
  if not rapi_cert.endswith("\n"):
426
    rapi_cert += "\n"
427
  if not confd_hmac_key.endswith("\n"):
428
    confd_hmac_key += "\n"
429

    
430
  # set up inter-node password and certificate and restarts the node daemon
431
  # and then connect with ssh to set password and start ganeti-noded
432
  # note that all the below variables are sanitized at this point,
433
  # either by being constants or by the checks above
434
  # TODO: Could this command exceed a shell's maximum command length?
435
  mycommand = ("umask 077 && "
436
               "cat > '%s' << '!EOF.' && \n"
437
               "%s!EOF.\n"
438
               "cat > '%s' << '!EOF.' && \n"
439
               "%s!EOF.\n"
440
               "cat > '%s' << '!EOF.' && \n"
441
               "%s!EOF.\n"
442
               "chmod 0400 %s %s %s && "
443
               "%s start %s" %
444
               (constants.NODED_CERT_FILE, noded_cert,
445
                constants.RAPI_CERT_FILE, rapi_cert,
446
                constants.CONFD_HMAC_KEY, confd_hmac_key,
447
                constants.NODED_CERT_FILE, constants.RAPI_CERT_FILE,
448
                constants.CONFD_HMAC_KEY,
449
                constants.DAEMON_UTIL, constants.NODED))
450

    
451
  result = sshrunner.Run(node, 'root', mycommand, batch=False,
452
                         ask_key=ssh_key_check,
453
                         use_cluster_key=False,
454
                         strict_host_check=ssh_key_check)
455
  if result.failed:
456
    raise errors.OpExecError("Remote command on node %s, error: %s,"
457
                             " output: %s" %
458
                             (node, result.fail_reason, result.output))
459

    
460
  _WaitForNodeDaemon(node)
461

    
462

    
463
def MasterFailover(no_voting=False):
464
  """Failover the master node.
465

466
  This checks that we are not already the master, and will cause the
467
  current master to cease being master, and the non-master to become
468
  new master.
469

470
  @type no_voting: boolean
471
  @param no_voting: force the operation without remote nodes agreement
472
                      (dangerous)
473

474
  """
475
  sstore = ssconf.SimpleStore()
476

    
477
  old_master, new_master = ssconf.GetMasterAndMyself(sstore)
478
  node_list = sstore.GetNodeList()
479
  mc_list = sstore.GetMasterCandidates()
480

    
481
  if old_master == new_master:
482
    raise errors.OpPrereqError("This commands must be run on the node"
483
                               " where you want the new master to be."
484
                               " %s is already the master" %
485
                               old_master, errors.ECODE_INVAL)
486

    
487
  if new_master not in mc_list:
488
    mc_no_master = [name for name in mc_list if name != old_master]
489
    raise errors.OpPrereqError("This node is not among the nodes marked"
490
                               " as master candidates. Only these nodes"
491
                               " can become masters. Current list of"
492
                               " master candidates is:\n"
493
                               "%s" % ('\n'.join(mc_no_master)),
494
                               errors.ECODE_STATE)
495

    
496
  if not no_voting:
497
    vote_list = GatherMasterVotes(node_list)
498

    
499
    if vote_list:
500
      voted_master = vote_list[0][0]
501
      if voted_master is None:
502
        raise errors.OpPrereqError("Cluster is inconsistent, most nodes did"
503
                                   " not respond.", errors.ECODE_ENVIRON)
504
      elif voted_master != old_master:
505
        raise errors.OpPrereqError("I have a wrong configuration, I believe"
506
                                   " the master is %s but the other nodes"
507
                                   " voted %s. Please resync the configuration"
508
                                   " of this node." %
509
                                   (old_master, voted_master),
510
                                   errors.ECODE_STATE)
511
  # end checks
512

    
513
  rcode = 0
514

    
515
  logging.info("Setting master to %s, old master: %s", new_master, old_master)
516

    
517
  result = rpc.RpcRunner.call_node_stop_master(old_master, True)
518
  msg = result.fail_msg
519
  if msg:
520
    logging.error("Could not disable the master role on the old master"
521
                 " %s, please disable manually: %s", old_master, msg)
522

    
523
  # Here we have a phase where no master should be running
524

    
525
  # instantiate a real config writer, as we now know we have the
526
  # configuration data
527
  cfg = config.ConfigWriter()
528

    
529
  cluster_info = cfg.GetClusterInfo()
530
  cluster_info.master_node = new_master
531
  # this will also regenerate the ssconf files, since we updated the
532
  # cluster info
533
  cfg.Update(cluster_info, logging.error)
534

    
535
  result = rpc.RpcRunner.call_node_start_master(new_master, True, no_voting)
536
  msg = result.fail_msg
537
  if msg:
538
    logging.error("Could not start the master role on the new master"
539
                  " %s, please check: %s", new_master, msg)
540
    rcode = 1
541

    
542
  return rcode
543

    
544

    
545
def GetMaster():
546
  """Returns the current master node.
547

548
  This is a separate function in bootstrap since it's needed by
549
  gnt-cluster, and instead of importing directly ssconf, it's better
550
  to abstract it in bootstrap, where we do use ssconf in other
551
  functions too.
552

553
  """
554
  sstore = ssconf.SimpleStore()
555

    
556
  old_master, _ = ssconf.GetMasterAndMyself(sstore)
557

    
558
  return old_master
559

    
560

    
561
def GatherMasterVotes(node_list):
562
  """Check the agreement on who is the master.
563

564
  This function will return a list of (node, number of votes), ordered
565
  by the number of votes. Errors will be denoted by the key 'None'.
566

567
  Note that the sum of votes is the number of nodes this machine
568
  knows, whereas the number of entries in the list could be different
569
  (if some nodes vote for another master).
570

571
  We remove ourselves from the list since we know that (bugs aside)
572
  since we use the same source for configuration information for both
573
  backend and boostrap, we'll always vote for ourselves.
574

575
  @type node_list: list
576
  @param node_list: the list of nodes to query for master info; the current
577
      node will be removed if it is in the list
578
  @rtype: list
579
  @return: list of (node, votes)
580

581
  """
582
  myself = utils.HostInfo().name
583
  try:
584
    node_list.remove(myself)
585
  except ValueError:
586
    pass
587
  if not node_list:
588
    # no nodes left (eventually after removing myself)
589
    return []
590
  results = rpc.RpcRunner.call_master_info(node_list)
591
  if not isinstance(results, dict):
592
    # this should not happen (unless internal error in rpc)
593
    logging.critical("Can't complete rpc call, aborting master startup")
594
    return [(None, len(node_list))]
595
  votes = {}
596
  for node in results:
597
    nres = results[node]
598
    data = nres.payload
599
    msg = nres.fail_msg
600
    fail = False
601
    if msg:
602
      logging.warning("Error contacting node %s: %s", node, msg)
603
      fail = True
604
    elif not isinstance(data, (tuple, list)) or len(data) < 3:
605
      logging.warning("Invalid data received from node %s: %s", node, data)
606
      fail = True
607
    if fail:
608
      if None not in votes:
609
        votes[None] = 0
610
      votes[None] += 1
611
      continue
612
    master_node = data[2]
613
    if master_node not in votes:
614
      votes[master_node] = 0
615
    votes[master_node] += 1
616

    
617
  vote_list = [v for v in votes.items()]
618
  # sort first on number of votes then on name, since we want None
619
  # sorted later if we have the half of the nodes not responding, and
620
  # half voting all for the same master
621
  vote_list.sort(key=lambda x: (x[1], x[0]), reverse=True)
622

    
623
  return vote_list