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