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#!/usr/bin/python -u |
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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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|
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|
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"""Master daemon program. |
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|
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Some classes deviates from the standard style guide since the |
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inheritance from parent classes requires it. |
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|
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""" |
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|
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|
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import os |
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import errno |
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import sys |
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import SocketServer |
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import time |
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import collections |
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import Queue |
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import random |
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import signal |
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import simplejson |
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import logging |
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|
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from cStringIO import StringIO |
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from optparse import OptionParser |
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|
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from ganeti import config |
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from ganeti import constants |
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from ganeti import mcpu |
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from ganeti import opcodes |
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from ganeti import jqueue |
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from ganeti import locking |
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from ganeti import luxi |
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from ganeti import utils |
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from ganeti import errors |
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from ganeti import ssconf |
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from ganeti import workerpool |
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from ganeti import rpc |
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from ganeti import bootstrap |
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|
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|
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CLIENT_REQUEST_WORKERS = 16 |
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|
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EXIT_NOTMASTER = constants.EXIT_NOTMASTER |
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EXIT_NODESETUP_ERROR = constants.EXIT_NODESETUP_ERROR |
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|
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|
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class ClientRequestWorker(workerpool.BaseWorker): |
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def RunTask(self, server, request, client_address): |
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"""Process the request. |
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|
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This is copied from the code in ThreadingMixIn. |
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|
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""" |
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try: |
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server.finish_request(request, client_address) |
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server.close_request(request) |
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except: |
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server.handle_error(request, client_address) |
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server.close_request(request) |
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|
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|
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class IOServer(SocketServer.UnixStreamServer): |
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"""IO thread class. |
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|
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This class takes care of initializing the other threads, setting |
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signal handlers (which are processed only in this thread), and doing |
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cleanup at shutdown. |
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|
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""" |
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def __init__(self, address, rqhandler): |
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"""IOServer constructor |
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|
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Args: |
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address: the address to bind this IOServer to |
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rqhandler: RequestHandler type object |
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|
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""" |
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SocketServer.UnixStreamServer.__init__(self, address, rqhandler) |
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|
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# We'll only start threads once we've forked. |
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self.context = None |
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self.request_workers = None |
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|
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def setup_queue(self): |
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self.context = GanetiContext() |
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self.request_workers = workerpool.WorkerPool(CLIENT_REQUEST_WORKERS, |
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ClientRequestWorker) |
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|
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def process_request(self, request, client_address): |
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"""Add task to workerpool to process request. |
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|
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""" |
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self.request_workers.AddTask(self, request, client_address) |
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|
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def serve_forever(self): |
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"""Handle one request at a time until told to quit.""" |
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sighandler = utils.SignalHandler([signal.SIGINT, signal.SIGTERM]) |
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try: |
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while not sighandler.called: |
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self.handle_request() |
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finally: |
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sighandler.Reset() |
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|
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def server_cleanup(self): |
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"""Cleanup the server. |
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|
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This involves shutting down the processor threads and the master |
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socket. |
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|
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""" |
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try: |
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self.server_close() |
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finally: |
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if self.request_workers: |
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self.request_workers.TerminateWorkers() |
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if self.context: |
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self.context.jobqueue.Shutdown() |
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|
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|
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class ClientRqHandler(SocketServer.BaseRequestHandler): |
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"""Client handler""" |
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EOM = '\3' |
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READ_SIZE = 4096 |
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|
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def setup(self): |
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self._buffer = "" |
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self._msgs = collections.deque() |
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self._ops = ClientOps(self.server) |
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|
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def handle(self): |
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while True: |
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msg = self.read_message() |
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if msg is None: |
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logging.info("client closed connection") |
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break |
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|
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request = simplejson.loads(msg) |
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logging.debug("request: %s", request) |
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if not isinstance(request, dict): |
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logging.error("wrong request received: %s", msg) |
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break |
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|
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method = request.get(luxi.KEY_METHOD, None) |
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args = request.get(luxi.KEY_ARGS, None) |
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if method is None or args is None: |
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logging.error("no method or args in request") |
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break |
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|
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success = False |
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try: |
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result = self._ops.handle_request(method, args) |
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success = True |
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except errors.GenericError, err: |
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success = False |
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result = (err.__class__.__name__, err.args) |
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except: |
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logging.error("Unexpected exception", exc_info=True) |
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err = sys.exc_info() |
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result = "Caught exception: %s" % str(err[1]) |
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|
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response = { |
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luxi.KEY_SUCCESS: success, |
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luxi.KEY_RESULT: result, |
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} |
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logging.debug("response: %s", response) |
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self.send_message(simplejson.dumps(response)) |
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|
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def read_message(self): |
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while not self._msgs: |
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data = self.request.recv(self.READ_SIZE) |
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if not data: |
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return None |
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new_msgs = (self._buffer + data).split(self.EOM) |
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self._buffer = new_msgs.pop() |
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self._msgs.extend(new_msgs) |
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return self._msgs.popleft() |
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|
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def send_message(self, msg): |
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#print "sending", msg |
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self.request.sendall(msg + self.EOM) |
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|
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|
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class ClientOps: |
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"""Class holding high-level client operations.""" |
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def __init__(self, server): |
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self.server = server |
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|
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def handle_request(self, method, args): |
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queue = self.server.context.jobqueue |
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|
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# TODO: Parameter validation |
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|
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if method == luxi.REQ_SUBMIT_JOB: |
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ops = [opcodes.OpCode.LoadOpCode(state) for state in args] |
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return queue.SubmitJob(ops) |
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|
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elif method == luxi.REQ_CANCEL_JOB: |
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job_id = args |
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return queue.CancelJob(job_id) |
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|
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elif method == luxi.REQ_ARCHIVE_JOB: |
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job_id = args |
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return queue.ArchiveJob(job_id) |
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|
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elif method == luxi.REQ_AUTOARCHIVE_JOBS: |
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age = args |
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return queue.AutoArchiveJobs(age) |
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|
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elif method == luxi.REQ_WAIT_FOR_JOB_CHANGE: |
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(job_id, fields, prev_job_info, prev_log_serial, timeout) = args |
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return queue.WaitForJobChanges(job_id, fields, prev_job_info, |
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prev_log_serial, timeout) |
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|
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elif method == luxi.REQ_QUERY_JOBS: |
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(job_ids, fields) = args |
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return queue.QueryJobs(job_ids, fields) |
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|
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elif method == luxi.REQ_QUERY_INSTANCES: |
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(names, fields) = args |
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op = opcodes.OpQueryInstances(names=names, output_fields=fields) |
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return self._Query(op) |
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|
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elif method == luxi.REQ_QUERY_NODES: |
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(names, fields) = args |
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op = opcodes.OpQueryNodes(names=names, output_fields=fields) |
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return self._Query(op) |
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|
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elif method == luxi.REQ_QUERY_EXPORTS: |
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nodes = args |
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op = opcodes.OpQueryExports(nodes=nodes) |
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return self._Query(op) |
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|
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elif method == luxi.REQ_QUERY_CONFIG_VALUES: |
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fields = args |
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op = opcodes.OpQueryConfigValues(output_fields=fields) |
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return self._Query(op) |
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|
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elif method == luxi.REQ_QUEUE_SET_DRAIN_FLAG: |
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drain_flag = args |
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return queue.SetDrainFlag(drain_flag) |
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|
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else: |
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raise ValueError("Invalid operation") |
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|
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def _DummyLog(self, *args): |
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pass |
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|
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def _Query(self, op): |
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"""Runs the specified opcode and returns the result. |
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|
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""" |
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proc = mcpu.Processor(self.server.context) |
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# TODO: Where should log messages go? |
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return proc.ExecOpCode(op, self._DummyLog, None) |
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|
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|
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class GanetiContext(object): |
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"""Context common to all ganeti threads. |
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This class creates and holds common objects shared by all threads. |
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|
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""" |
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_instance = None |
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|
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def __init__(self): |
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"""Constructs a new GanetiContext object. |
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|
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There should be only a GanetiContext object at any time, so this |
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function raises an error if this is not the case. |
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|
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""" |
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assert self.__class__._instance is None, "double GanetiContext instance" |
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|
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# Create global configuration object |
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self.cfg = config.ConfigWriter() |
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|
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# Locking manager |
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self.glm = locking.GanetiLockManager( |
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self.cfg.GetNodeList(), |
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self.cfg.GetInstanceList()) |
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|
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# Job queue |
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self.jobqueue = jqueue.JobQueue(self) |
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|
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# setting this also locks the class against attribute modifications |
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self.__class__._instance = self |
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|
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def __setattr__(self, name, value): |
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"""Setting GanetiContext attributes is forbidden after initialization. |
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|
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""" |
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assert self.__class__._instance is None, "Attempt to modify Ganeti Context" |
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object.__setattr__(self, name, value) |
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|
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def AddNode(self, node): |
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"""Adds a node to the configuration and lock manager. |
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|
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""" |
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# Add it to the configuration |
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self.cfg.AddNode(node) |
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|
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# If preseeding fails it'll not be added |
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self.jobqueue.AddNode(node) |
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|
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# Add the new node to the Ganeti Lock Manager |
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self.glm.add(locking.LEVEL_NODE, node.name) |
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|
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def ReaddNode(self, node): |
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"""Updates a node that's already in the configuration |
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|
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""" |
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# Synchronize the queue again |
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self.jobqueue.AddNode(node) |
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|
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def RemoveNode(self, name): |
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"""Removes a node from the configuration and lock manager. |
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|
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""" |
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# Remove node from configuration |
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self.cfg.RemoveNode(name) |
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|
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# Notify job queue |
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self.jobqueue.RemoveNode(name) |
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|
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# Remove the node from the Ganeti Lock Manager |
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self.glm.remove(locking.LEVEL_NODE, name) |
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|
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|
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def ParseOptions(): |
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"""Parse the command line options. |
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|
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Returns: |
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(options, args) as from OptionParser.parse_args() |
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|
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""" |
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parser = OptionParser(description="Ganeti master daemon", |
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usage="%prog [-f] [-d]", |
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version="%%prog (ganeti) %s" % |
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constants.RELEASE_VERSION) |
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|
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parser.add_option("-f", "--foreground", dest="fork", |
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help="Don't detach from the current terminal", |
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default=True, action="store_false") |
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parser.add_option("-d", "--debug", dest="debug", |
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help="Enable some debug messages", |
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default=False, action="store_true") |
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options, args = parser.parse_args() |
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return options, args |
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|
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|
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def CheckAgreement(): |
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"""Check the agreement on who is the master. |
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|
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The function uses a very simple algorithm: we must get more positive |
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than negative answers. Since in most of the cases we are the master, |
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we'll use our own config file for getting the node list. In the |
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future we could collect the current node list from our (possibly |
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obsolete) known nodes. |
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|
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In order to account for cold-start of all nodes, we retry for up to |
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a minute until we get a real answer as the top-voted one. If the |
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nodes are more out-of-sync, for now manual startup of the master |
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should be attempted. |
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|
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Note that for a even number of nodes cluster, we need at least half |
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of the nodes (beside ourselves) to vote for us. This creates a |
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problem on two-node clusters, since in this case we require the |
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other node to be up too to confirm our status. |
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|
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""" |
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myself = utils.HostInfo().name |
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#temp instantiation of a config writer, used only to get the node list |
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cfg = config.ConfigWriter() |
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node_list = cfg.GetNodeList() |
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del cfg |
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retries = 6 |
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while retries > 0: |
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votes = bootstrap.GatherMasterVotes(node_list) |
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if not votes: |
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# empty node list, this is a one node cluster |
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return True |
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if votes[0][0] is None: |
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retries -= 1 |
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time.sleep(10) |
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continue |
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break |
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if retries == 0: |
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logging.critical("Cluster inconsistent, most of the nodes didn't answer" |
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" after multiple retries. Aborting startup") |
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return False |
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# here a real node is at the top of the list |
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all_votes = sum(item[1] for item in votes) |
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top_node, top_votes = votes[0] |
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result = False |
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if top_node != myself: |
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logging.critical("It seems we are not the master (top-voted node" |
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" is %s)", top_node) |
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elif top_votes < all_votes - top_votes: |
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logging.critical("It seems we are not the master (%d votes for," |
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" %d votes against)", top_votes, all_votes - top_votes) |
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else: |
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result = True |
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|
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return result |
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|
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|
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def main(): |
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"""Main function""" |
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|
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options, args = ParseOptions() |
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utils.debug = options.debug |
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utils.no_fork = True |
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|
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rpc.Init() |
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try: |
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ssconf.CheckMaster(options.debug) |
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|
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# we believe we are the master, let's ask the other nodes... |
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if not CheckAgreement(): |
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return |
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|
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try: |
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os.mkdir(constants.SOCKET_DIR, constants.SOCKET_DIR_MODE) |
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except EnvironmentError, err: |
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if err.errno != errno.EEXIST: |
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raise errors.GenericError("Cannot create socket directory" |
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" '%s': %s" % (constants.SOCKET_DIR, err)) |
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|
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master = IOServer(constants.MASTER_SOCKET, ClientRqHandler) |
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finally: |
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rpc.Shutdown() |
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|
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# become a daemon |
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if options.fork: |
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utils.Daemonize(logfile=constants.LOG_MASTERDAEMON, |
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noclose_fds=[master.fileno()]) |
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|
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utils.WritePidFile(constants.MASTERD_PID) |
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try: |
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utils.SetupLogging(constants.LOG_MASTERDAEMON, debug=options.debug, |
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stderr_logging=not options.fork) |
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|
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logging.info("Ganeti master daemon startup") |
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|
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rpc.Init() |
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try: |
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# activate ip |
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master_node = ssconf.SimpleConfigReader().GetMasterNode() |
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if not rpc.RpcRunner.call_node_start_master(master_node, False): |
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logging.error("Can't activate master IP address") |
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|
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master.setup_queue() |
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try: |
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master.serve_forever() |
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finally: |
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master.server_cleanup() |
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finally: |
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rpc.Shutdown() |
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finally: |
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utils.RemovePidFile(constants.MASTERD_PID) |
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|
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|
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if __name__ == "__main__": |
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main() |