mcpu.py 13.6 KB
Newer Older
Iustin Pop's avatar
Iustin Pop committed
1
#
Iustin Pop's avatar
Iustin Pop committed
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
#

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


"""Module implementing the logic behind the cluster operations

This module implements the logic for doing operations in the cluster. There
are two kinds of classes defined:
  - logical units, which know how to deal with their specific opcode only
  - the processor, which dispatches the opcodes to their logical units

"""

31
import logging
Iustin Pop's avatar
Iustin Pop committed
32
33
34
35
36
37

from ganeti import opcodes
from ganeti import constants
from ganeti import errors
from ganeti import rpc
from ganeti import cmdlib
38
from ganeti import locking
Iustin Pop's avatar
Iustin Pop committed
39

40

Iustin Pop's avatar
Iustin Pop committed
41
42
43
44
45
46
47
class Processor(object):
  """Object which runs OpCodes"""
  DISPATCH_TABLE = {
    # Cluster
    opcodes.OpDestroyCluster: cmdlib.LUDestroyCluster,
    opcodes.OpQueryClusterInfo: cmdlib.LUQueryClusterInfo,
    opcodes.OpVerifyCluster: cmdlib.LUVerifyCluster,
48
    opcodes.OpQueryConfigValues: cmdlib.LUQueryConfigValues,
49
    opcodes.OpRenameCluster: cmdlib.LURenameCluster,
50
    opcodes.OpVerifyDisks: cmdlib.LUVerifyDisks,
51
    opcodes.OpSetClusterParams: cmdlib.LUSetClusterParams,
52
    opcodes.OpRedistributeConfig: cmdlib.LURedistributeConfig,
Iustin Pop's avatar
Iustin Pop committed
53
54
55
    # node lu
    opcodes.OpAddNode: cmdlib.LUAddNode,
    opcodes.OpQueryNodes: cmdlib.LUQueryNodes,
56
    opcodes.OpQueryNodeVolumes: cmdlib.LUQueryNodeVolumes,
Iustin Pop's avatar
Iustin Pop committed
57
    opcodes.OpRemoveNode: cmdlib.LURemoveNode,
Iustin Pop's avatar
Iustin Pop committed
58
    opcodes.OpSetNodeParams: cmdlib.LUSetNodeParams,
Iustin Pop's avatar
Iustin Pop committed
59
    opcodes.OpPowercycleNode: cmdlib.LUPowercycleNode,
60
    opcodes.OpEvacuateNode: cmdlib.LUEvacuateNode,
61
    opcodes.OpMigrateNode: cmdlib.LUMigrateNode,
Iustin Pop's avatar
Iustin Pop committed
62
63
    # instance lu
    opcodes.OpCreateInstance: cmdlib.LUCreateInstance,
64
    opcodes.OpReinstallInstance: cmdlib.LUReinstallInstance,
Iustin Pop's avatar
Iustin Pop committed
65
    opcodes.OpRemoveInstance: cmdlib.LURemoveInstance,
66
    opcodes.OpRenameInstance: cmdlib.LURenameInstance,
Iustin Pop's avatar
Iustin Pop committed
67
68
69
    opcodes.OpActivateInstanceDisks: cmdlib.LUActivateInstanceDisks,
    opcodes.OpShutdownInstance: cmdlib.LUShutdownInstance,
    opcodes.OpStartupInstance: cmdlib.LUStartupInstance,
70
    opcodes.OpRebootInstance: cmdlib.LURebootInstance,
Iustin Pop's avatar
Iustin Pop committed
71
72
73
    opcodes.OpDeactivateInstanceDisks: cmdlib.LUDeactivateInstanceDisks,
    opcodes.OpReplaceDisks: cmdlib.LUReplaceDisks,
    opcodes.OpFailoverInstance: cmdlib.LUFailoverInstance,
74
    opcodes.OpMigrateInstance: cmdlib.LUMigrateInstance,
Iustin Pop's avatar
Iustin Pop committed
75
76
77
    opcodes.OpConnectConsole: cmdlib.LUConnectConsole,
    opcodes.OpQueryInstances: cmdlib.LUQueryInstances,
    opcodes.OpQueryInstanceData: cmdlib.LUQueryInstanceData,
78
    opcodes.OpSetInstanceParams: cmdlib.LUSetInstanceParams,
Iustin Pop's avatar
Iustin Pop committed
79
    opcodes.OpGrowDisk: cmdlib.LUGrowDisk,
Iustin Pop's avatar
Iustin Pop committed
80
81
82
83
84
    # os lu
    opcodes.OpDiagnoseOS: cmdlib.LUDiagnoseOS,
    # exports lu
    opcodes.OpQueryExports: cmdlib.LUQueryExports,
    opcodes.OpExportInstance: cmdlib.LUExportInstance,
85
    opcodes.OpRemoveExport: cmdlib.LURemoveExport,
86
87
    # tags lu
    opcodes.OpGetTags: cmdlib.LUGetTags,
Iustin Pop's avatar
Iustin Pop committed
88
    opcodes.OpSearchTags: cmdlib.LUSearchTags,
89
90
    opcodes.OpAddTags: cmdlib.LUAddTags,
    opcodes.OpDelTags: cmdlib.LUDelTags,
91
92
    # test lu
    opcodes.OpTestDelay: cmdlib.LUTestDelay,
93
    opcodes.OpTestAllocator: cmdlib.LUTestAllocator,
Iustin Pop's avatar
Iustin Pop committed
94
95
    }

96
  def __init__(self, context):
Iustin Pop's avatar
Iustin Pop committed
97
98
    """Constructor for Processor

99
100
101
    Args:
     - feedback_fn: the feedback function (taking one string) to be run when
                    interesting events are happening
Iustin Pop's avatar
Iustin Pop committed
102
    """
103
    self.context = context
104
    self._feedback_fn = None
105
    self.exclusive_BGL = False
Iustin Pop's avatar
Iustin Pop committed
106
    self.rpc = rpc.RpcRunner(context.cfg)
Iustin Pop's avatar
Iustin Pop committed
107

108
109
110
111
112
113
  def _ExecLU(self, lu):
    """Logical Unit execution sequence.

    """
    write_count = self.context.cfg.write_count
    lu.CheckPrereq()
Iustin Pop's avatar
Iustin Pop committed
114
    hm = HooksMaster(self.rpc.call_hooks_runner, self, lu)
115
116
117
    h_results = hm.RunPhase(constants.HOOKS_PHASE_PRE)
    lu.HooksCallBack(constants.HOOKS_PHASE_PRE, h_results,
                     self._feedback_fn, None)
118
119
120
121
122
123
124
125
126

    if getattr(lu.op, "dry_run", False):
      # in this mode, no post-hooks are run, and the config is not
      # written (as it might have been modified by another LU, and we
      # shouldn't do writeout on behalf of other threads
      self.LogInfo("dry-run mode requested, not actually executing"
                   " the operation")
      return lu.dry_run_result

127
128
129
130
131
132
133
134
135
136
137
138
    try:
      result = lu.Exec(self._feedback_fn)
      h_results = hm.RunPhase(constants.HOOKS_PHASE_POST)
      result = lu.HooksCallBack(constants.HOOKS_PHASE_POST, h_results,
                                self._feedback_fn, result)
    finally:
      # FIXME: This needs locks if not lu_class.REQ_BGL
      if write_count != self.context.cfg.write_count:
        hm.RunConfigUpdate()

    return result

139
140
141
142
143
144
145
146
  def _LockAndExecLU(self, lu, level):
    """Execute a Logical Unit, with the needed locks.

    This is a recursive function that starts locking the given level, and
    proceeds up, till there are no more locks to acquire. Then it executes the
    given LU and its opcodes.

    """
147
148
    adding_locks = level in lu.add_locks
    acquiring_locks = level in lu.needed_locks
149
    if level not in locking.LEVELS:
Iustin Pop's avatar
Iustin Pop committed
150
151
      if callable(self._run_notifier):
        self._run_notifier()
152
      result = self._ExecLU(lu)
153
154
155
156
157
158
    elif adding_locks and acquiring_locks:
      # We could both acquire and add locks at the same level, but for now we
      # don't need this, so we'll avoid the complicated code needed.
      raise NotImplementedError(
        "Can't declare locks to acquire when adding others")
    elif adding_locks or acquiring_locks:
Guido Trotter's avatar
Guido Trotter committed
159
      lu.DeclareLocks(level)
Guido Trotter's avatar
Guido Trotter committed
160
      share = lu.share_locks[level]
161
162
163
164
165
166
167
168
169
170
171
172
      if acquiring_locks:
        needed_locks = lu.needed_locks[level]
        lu.acquired_locks[level] = self.context.glm.acquire(level,
                                                            needed_locks,
                                                            shared=share)
      else: # adding_locks
        add_locks = lu.add_locks[level]
        lu.remove_locks[level] = add_locks
        try:
          self.context.glm.add(level, add_locks, acquired=1, shared=share)
        except errors.LockError:
          raise errors.OpPrereqError(
Michael Hanselmann's avatar
Michael Hanselmann committed
173
            "Couldn't add locks (%s), probably because of a race condition"
174
            " with another job, who added them first" % add_locks)
175
      try:
176
177
178
179
180
181
182
        try:
          if adding_locks:
            lu.acquired_locks[level] = add_locks
          result = self._LockAndExecLU(lu, level + 1)
        finally:
          if level in lu.remove_locks:
            self.context.glm.remove(level, lu.remove_locks[level])
183
      finally:
184
        if self.context.glm.is_owned(level):
185
186
          self.context.glm.release(level)
    else:
187
      result = self._LockAndExecLU(lu, level + 1)
188
189
190

    return result

Iustin Pop's avatar
Iustin Pop committed
191
  def ExecOpCode(self, op, feedback_fn, run_notifier):
Iustin Pop's avatar
Iustin Pop committed
192
193
    """Execute an opcode.

Iustin Pop's avatar
Iustin Pop committed
194
195
196
197
198
199
200
201
    @type op: an OpCode instance
    @param op: the opcode to be executed
    @type feedback_fn: a function that takes a single argument
    @param feedback_fn: this function will be used as feedback from the LU
                        code to the end-user
    @type run_notifier: callable (no arguments) or None
    @param run_notifier:  this function (if callable) will be called when
                          we are about to call the lu's Exec() method, that
Michael Hanselmann's avatar
Michael Hanselmann committed
202
                          is, after we have acquired all locks
Iustin Pop's avatar
Iustin Pop committed
203
204
205

    """
    if not isinstance(op, opcodes.OpCode):
206
207
      raise errors.ProgrammerError("Non-opcode instance passed"
                                   " to ExecOpcode")
Iustin Pop's avatar
Iustin Pop committed
208

209
    self._feedback_fn = feedback_fn
Iustin Pop's avatar
Iustin Pop committed
210
    self._run_notifier = run_notifier
Iustin Pop's avatar
Iustin Pop committed
211
212
    lu_class = self.DISPATCH_TABLE.get(op.__class__, None)
    if lu_class is None:
213
      raise errors.OpCodeUnknown("Unknown opcode")
Iustin Pop's avatar
Iustin Pop committed
214

215
216
    # Acquire the Big Ganeti Lock exclusively if this LU requires it, and in a
    # shared fashion otherwise (to prevent concurrent run with an exclusive LU.
Guido Trotter's avatar
Guido Trotter committed
217
    self.context.glm.acquire(locking.LEVEL_CLUSTER, [locking.BGL],
218
                             shared=not lu_class.REQ_BGL)
219
    try:
220
      self.exclusive_BGL = lu_class.REQ_BGL
Iustin Pop's avatar
Iustin Pop committed
221
      lu = lu_class(self, op, self.context, self.rpc)
222
      lu.ExpandNames()
223
      assert lu.needed_locks is not None, "needed_locks not set by LU"
224
      result = self._LockAndExecLU(lu, locking.LEVEL_INSTANCE)
225
    finally:
Guido Trotter's avatar
Guido Trotter committed
226
      self.context.glm.release(locking.LEVEL_CLUSTER)
227
      self.exclusive_BGL = False
228

Iustin Pop's avatar
Iustin Pop committed
229
230
    return result

231
232
233
234
  def LogStep(self, current, total, message):
    """Log a change in LU execution progress.

    """
235
    logging.debug("Step %d/%d %s", current, total, message)
236
237
    self._feedback_fn("STEP %d/%d %s" % (current, total, message))

238
  def LogWarning(self, message, *args, **kwargs):
239
240
    """Log a warning to the logs and the user.

241
242
243
244
    The optional keyword argument is 'hint' and can be used to show a
    hint to the user (presumably related to the warning). If the
    message is empty, it will not be printed at all, allowing one to
    show only a hint.
245

246
247
248
249
250
251
252
253
254
255
256
257
    """
    assert not kwargs or (len(kwargs) == 1 and "hint" in kwargs), \
           "Invalid keyword arguments for LogWarning (%s)" % str(kwargs)
    if args:
      message = message % tuple(args)
    if message:
      logging.warning(message)
      self._feedback_fn(" - WARNING: %s" % message)
    if "hint" in kwargs:
      self._feedback_fn("      Hint: %s" % kwargs["hint"])

  def LogInfo(self, message, *args):
258
259
260
    """Log an informational message to the logs and the user.

    """
261
262
    if args:
      message = message % tuple(args)
263
    logging.info(message)
264
265
    self._feedback_fn(" - INFO: %s" % message)

Iustin Pop's avatar
Iustin Pop committed
266
267
268
269
270
271
272
273
274
275
276
277
278

class HooksMaster(object):
  """Hooks master.

  This class distributes the run commands to the nodes based on the
  specific LU class.

  In order to remove the direct dependency on the rpc module, the
  constructor needs a function which actually does the remote
  call. This will usually be rpc.call_hooks_runner, but any function
  which behaves the same works.

  """
279
  def __init__(self, callfn, proc, lu):
Iustin Pop's avatar
Iustin Pop committed
280
    self.callfn = callfn
281
    self.proc = proc
Iustin Pop's avatar
Iustin Pop committed
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
    self.lu = lu
    self.op = lu.op
    self.env, node_list_pre, node_list_post = self._BuildEnv()
    self.node_list = {constants.HOOKS_PHASE_PRE: node_list_pre,
                      constants.HOOKS_PHASE_POST: node_list_post}

  def _BuildEnv(self):
    """Compute the environment and the target nodes.

    Based on the opcode and the current node list, this builds the
    environment for the hooks and the target node list for the run.

    """
    env = {
      "PATH": "/sbin:/bin:/usr/sbin:/usr/bin",
      "GANETI_HOOKS_VERSION": constants.HOOKS_VERSION,
      "GANETI_OP_CODE": self.op.OP_ID,
      "GANETI_OBJECT_TYPE": self.lu.HTYPE,
300
      "GANETI_DATA_DIR": constants.DATA_DIR,
Iustin Pop's avatar
Iustin Pop committed
301
302
      }

303
304
305
306
307
308
309
    if self.lu.HPATH is not None:
      lu_env, lu_nodes_pre, lu_nodes_post = self.lu.BuildHooksEnv()
      if lu_env:
        for key in lu_env:
          env["GANETI_" + key] = lu_env[key]
    else:
      lu_nodes_pre = lu_nodes_post = []
Iustin Pop's avatar
Iustin Pop committed
310

311
312
313
314
315
316
317
318
319
320
321
    return env, frozenset(lu_nodes_pre), frozenset(lu_nodes_post)

  def _RunWrapper(self, node_list, hpath, phase):
    """Simple wrapper over self.callfn.

    This method fixes the environment before doing the rpc call.

    """
    env = self.env.copy()
    env["GANETI_HOOKS_PHASE"] = phase
    env["GANETI_HOOKS_PATH"] = hpath
Michael Hanselmann's avatar
Michael Hanselmann committed
322
323
324
    if self.lu.cfg is not None:
      env["GANETI_CLUSTER"] = self.lu.cfg.GetClusterName()
      env["GANETI_MASTER"] = self.lu.cfg.GetMasterNode()
Iustin Pop's avatar
Iustin Pop committed
325

326
    env = dict([(str(key), str(val)) for key, val in env.iteritems()])
Iustin Pop's avatar
Iustin Pop committed
327

328
    return self.callfn(node_list, hpath, phase, env)
Iustin Pop's avatar
Iustin Pop committed
329
330
331
332
333
334

  def RunPhase(self, phase):
    """Run all the scripts for a phase.

    This is the main function of the HookMaster.

Iustin Pop's avatar
Iustin Pop committed
335
336
337
338
    @param phase: one of L{constants.HOOKS_PHASE_POST} or
        L{constants.HOOKS_PHASE_PRE}; it denotes the hooks phase
    @return: the processed results of the hooks multi-node rpc call
    @raise errors.HooksFailure: on communication failure to the nodes
339

Iustin Pop's avatar
Iustin Pop committed
340
341
    """
    if not self.node_list[phase]:
342
343
344
      # empty node list, we should not attempt to run this as either
      # we're in the cluster init phase and the rpc client part can't
      # even attempt to run, or this LU doesn't do hooks at all
Iustin Pop's avatar
Iustin Pop committed
345
      return
346
347
    hpath = self.lu.HPATH
    results = self._RunWrapper(self.node_list[phase], hpath, phase)
Iustin Pop's avatar
Iustin Pop committed
348
349
350
    if phase == constants.HOOKS_PHASE_PRE:
      errs = []
      if not results:
351
        raise errors.HooksFailure("Communication failure")
Iustin Pop's avatar
Iustin Pop committed
352
353
      for node_name in results:
        res = results[node_name]
354
        if res.offline:
355
          continue
356
357
358
359
360
361
        msg = res.RemoteFailMsg()
        if msg:
          self.proc.LogWarning("Communication failure to node %s: %s",
                               node_name, msg)
          continue
        for script, hkr, output in res.payload:
Iustin Pop's avatar
Iustin Pop committed
362
363
364
          if hkr == constants.HKR_FAIL:
            errs.append((node_name, script, output))
      if errs:
365
        raise errors.HooksAbort(errs)
366
    return results
367
368
369
370
371
372
373
374
375
376

  def RunConfigUpdate(self):
    """Run the special configuration update hook

    This is a special hook that runs only on the master after each
    top-level LI if the configuration has been updated.

    """
    phase = constants.HOOKS_PHASE_POST
    hpath = constants.HOOKS_NAME_CFGUPDATE
Michael Hanselmann's avatar
Michael Hanselmann committed
377
    nodes = [self.lu.cfg.GetMasterNode()]
Iustin Pop's avatar
Iustin Pop committed
378
    self._RunWrapper(nodes, hpath, phase)