# 02110-1301, USA.
-"""Tool to restart erronously downed virtual machines.
+"""Tool to restart erroneously downed virtual machines.
This program and set of classes implement a watchdog to restart
virtual machines in a Ganeti cluster that have crashed or been killed
"""
+# pylint: disable-msg=C0103,W0142
+
+# C0103: Invalid name ganeti-watcher
+
import os
import sys
import time
from ganeti import utils
from ganeti import constants
from ganeti import serializer
-from ganeti import ssconf
from ganeti import errors
from ganeti import opcodes
-from ganeti import logger
from ganeti import cli
+from ganeti import luxi
+from ganeti import ssconf
+from ganeti import bdev
+from ganeti import hypervisor
+from ganeti.confd import client as confd_client
MAXTRIES = 5
BAD_STATES = ['ERROR_down']
-HELPLESS_STATES = ['ERROR_nodedown']
+HELPLESS_STATES = ['ERROR_nodedown', 'ERROR_nodeoffline']
NOTICE = 'NOTICE'
ERROR = 'ERROR'
KEY_RESTART_COUNT = "restart_count"
"""Exception raised when this host is not the master."""
-def Indent(s, prefix='| '):
- """Indent a piece of text with a given prefix before each line.
+def ShouldPause():
+ """Check whether we should pause.
+
+ """
+ return bool(utils.ReadWatcherPauseFile(constants.WATCHER_PAUSEFILE))
+
+
+def StartNodeDaemons():
+ """Start all the daemons that should be running on all nodes.
+
+ """
+ # on master or not, try to start the node daemon
+ utils.EnsureDaemon(constants.NODED)
+ # start confd as well. On non candidates it will be in disabled mode.
+ utils.EnsureDaemon(constants.CONFD)
+
- Args:
- s: The string to indent
- prefix: The string to prepend each line.
+def RunWatcherHooks():
+ """Run the watcher hooks.
"""
- return "%s%s\n" % (prefix, ('\n' + prefix).join(s.splitlines()))
+ hooks_dir = utils.PathJoin(constants.HOOKS_BASE_DIR,
+ constants.HOOKS_NAME_WATCHER)
+ if not os.path.isdir(hooks_dir):
+ return
+
+ try:
+ results = utils.RunParts(hooks_dir)
+ except Exception, msg: # pylint: disable-msg=W0703
+ logging.critical("RunParts %s failed: %s", hooks_dir, msg)
+
+ for (relname, status, runresult) in results:
+ if status == constants.RUNPARTS_SKIP:
+ logging.debug("Watcher hook %s: skipped", relname)
+ elif status == constants.RUNPARTS_ERR:
+ logging.warning("Watcher hook %s: error (%s)", relname, runresult)
+ elif status == constants.RUNPARTS_RUN:
+ if runresult.failed:
+ logging.warning("Watcher hook %s: failed (exit: %d) (output: %s)",
+ relname, runresult.exit_code, runresult.output)
+ else:
+ logging.debug("Watcher hook %s: success (output: %s)", relname,
+ runresult.output)
+
+
+class NodeMaintenance(object):
+ """Talks to confd daemons and possible shutdown instances/drbd devices.
+
+ """
+ def __init__(self):
+ self.store_cb = confd_client.StoreResultCallback()
+ self.filter_cb = confd_client.ConfdFilterCallback(self.store_cb)
+ self.confd_client = confd_client.GetConfdClient(self.filter_cb)
+
+ @staticmethod
+ def ShouldRun():
+ """Checks whether node maintenance should run.
+
+ """
+ try:
+ return ssconf.SimpleStore().GetMaintainNodeHealth()
+ except errors.ConfigurationError, err:
+ logging.error("Configuration error, not activating node maintenance: %s",
+ err)
+ return False
+
+ @staticmethod
+ def GetRunningInstances():
+ """Compute list of hypervisor/running instances.
+
+ """
+ hyp_list = ssconf.SimpleStore().GetHypervisorList()
+ results = []
+ for hv_name in hyp_list:
+ try:
+ hv = hypervisor.GetHypervisor(hv_name)
+ ilist = hv.ListInstances()
+ results.extend([(iname, hv_name) for iname in ilist])
+ except: # pylint: disable-msg=W0702
+ logging.error("Error while listing instances for hypervisor %s",
+ hv_name, exc_info=True)
+ return results
+
+ @staticmethod
+ def GetUsedDRBDs():
+ """Get list of used DRBD minors.
+
+ """
+ return bdev.DRBD8.GetUsedDevs().keys()
+
+ @classmethod
+ def DoMaintenance(cls, role):
+ """Maintain the instance list.
+
+ """
+ if role == constants.CONFD_NODE_ROLE_OFFLINE:
+ inst_running = cls.GetRunningInstances()
+ cls.ShutdownInstances(inst_running)
+ drbd_running = cls.GetUsedDRBDs()
+ cls.ShutdownDRBD(drbd_running)
+ else:
+ logging.debug("Not doing anything for role %s", role)
+
+ @staticmethod
+ def ShutdownInstances(inst_running):
+ """Shutdown running instances.
+
+ """
+ names_running = set([i[0] for i in inst_running])
+ if names_running:
+ logging.info("Following instances should not be running,"
+ " shutting them down: %s", utils.CommaJoin(names_running))
+ # this dictionary will collapse duplicate instance names (only
+ # xen pvm/vhm) into a single key, which is fine
+ i2h = dict(inst_running)
+ for name in names_running:
+ hv_name = i2h[name]
+ hv = hypervisor.GetHypervisor(hv_name)
+ hv.StopInstance(None, force=True, name=name)
+
+ @staticmethod
+ def ShutdownDRBD(drbd_running):
+ """Shutdown active DRBD devices.
+
+ """
+ if drbd_running:
+ logging.info("Following DRBD minors should not be active,"
+ " shutting them down: %s", utils.CommaJoin(drbd_running))
+ for minor in drbd_running:
+ # pylint: disable-msg=W0212
+ # using the private method as is, pending enhancements to the DRBD
+ # interface
+ bdev.DRBD8._ShutdownAll(minor)
+
+ def Exec(self):
+ """Check node status versus cluster desired state.
+
+ """
+ my_name = utils.HostInfo().name
+ req = confd_client.ConfdClientRequest(type=
+ constants.CONFD_REQ_NODE_ROLE_BYNAME,
+ query=my_name)
+ self.confd_client.SendRequest(req, async=False, coverage=-1)
+ timed_out, _, _ = self.confd_client.WaitForReply(req.rsalt)
+ if not timed_out:
+ # should have a valid response
+ status, result = self.store_cb.GetResponse(req.rsalt)
+ assert status, "Missing result but received replies"
+ if not self.filter_cb.consistent[req.rsalt]:
+ logging.warning("Inconsistent replies, not doing anything")
+ return
+ self.DoMaintenance(result.server_reply.answer)
+ else:
+ logging.warning("Confd query timed out, cannot do maintenance actions")
class WatcherState(object):
"""Interface to a state file recording restart attempts.
"""
- def __init__(self):
+ def __init__(self, statefile):
"""Open, lock, read and parse the file.
- Raises exception on lock contention.
+ @type statefile: file
+ @param statefile: State file object
"""
- # The two-step dance below is necessary to allow both opening existing
- # file read/write and creating if not existing. Vanilla open will truncate
- # an existing file -or- allow creating if not existing.
- fd = os.open(constants.WATCHER_STATEFILE, os.O_RDWR | os.O_CREAT)
- self.statefile = os.fdopen(fd, 'w+')
-
- utils.LockFile(self.statefile.fileno())
+ self.statefile = statefile
try:
- self._data = serializer.Load(self.statefile.read())
- except Exception, msg:
+ state_data = self.statefile.read()
+ if not state_data:
+ self._data = {}
+ else:
+ self._data = serializer.Load(state_data)
+ except Exception, msg: # pylint: disable-msg=W0703
# Ignore errors while loading the file and treat it as empty
self._data = {}
- logging.warning(("Empty or invalid state file. Using defaults."
+ logging.warning(("Invalid state file. Using defaults."
" Error message: %s"), msg)
if "instance" not in self._data:
def NumberOfRestartAttempts(self, instance):
"""Returns number of previous restart attempts.
- Args:
- instance - the instance to look up.
+ @type instance: L{Instance}
+ @param instance: the instance to look up
"""
idata = self._data["instance"]
def RecordRestartAttempt(self, instance):
"""Record a restart attempt.
- Args:
- instance - the instance being restarted
+ @type instance: L{Instance}
+ @param instance: the instance being restarted
"""
idata = self._data["instance"]
inst[KEY_RESTART_COUNT] = inst.get(KEY_RESTART_COUNT, 0) + 1
def RemoveInstance(self, instance):
- """Update state to reflect that a machine is running, i.e. remove record.
+ """Update state to reflect that a machine is running.
- Args:
- instance - the instance to remove from books
+ This method removes the record for a named instance (as we only
+ track down instances).
- This method removes the record for a named instance.
+ @type instance: L{Instance}
+ @param instance: the instance to remove from books
"""
idata = self._data["instance"]
class Instance(object):
"""Abstraction for a Virtual Machine instance.
- Methods:
- Restart(): issue a command to restart the represented machine.
-
"""
def __init__(self, name, state, autostart):
self.name = name
"""Encapsulates the start of an instance.
"""
- op = opcodes.OpStartupInstance(instance_name=self.name,
- force=False,
- extra_args=None)
+ op = opcodes.OpStartupInstance(instance_name=self.name, force=False)
cli.SubmitOpCode(op, cl=client)
def ActivateDisks(self):
cli.SubmitOpCode(op, cl=client)
-def GetInstanceList(with_secondaries=None):
+def GetClusterData():
"""Get a list of instances on this cluster.
"""
- fields = ["name", "status", "admin_state"]
+ op1_fields = ["name", "status", "admin_state", "snodes"]
+ op1 = opcodes.OpQueryInstances(output_fields=op1_fields, names=[],
+ use_locking=True)
+ op2_fields = ["name", "bootid", "offline"]
+ op2 = opcodes.OpQueryNodes(output_fields=op2_fields, names=[],
+ use_locking=True)
- if with_secondaries is not None:
- fields.append("snodes")
+ job_id = client.SubmitJob([op1, op2])
- result = client.QueryInstances([], fields)
+ all_results = cli.PollJob(job_id, cl=client, feedback_fn=logging.debug)
- instances = []
- for fields in result:
- if with_secondaries is not None:
- (name, status, autostart, snodes) = fields
+ logging.debug("Got data from cluster, writing instance status file")
- if not snodes:
- continue
+ result = all_results[0]
+ smap = {}
- for node in with_secondaries:
- if node in snodes:
- break
- else:
- continue
+ instances = {}
- else:
- (name, status, autostart) = fields
+ # write the upfile
+ up_data = "".join(["%s %s\n" % (fields[0], fields[1]) for fields in result])
+ utils.WriteFile(file_name=constants.INSTANCE_UPFILE, data=up_data)
- instances.append(Instance(name, status, autostart))
+ for fields in result:
+ (name, status, autostart, snodes) = fields
- return instances
+ # update the secondary node map
+ for node in snodes:
+ if node not in smap:
+ smap[node] = []
+ smap[node].append(name)
+ instances[name] = Instance(name, status, autostart)
-def GetNodeBootIDs():
- """Get a dict mapping nodes to boot IDs.
+ nodes = dict([(name, (bootid, offline))
+ for name, bootid, offline in all_results[1]])
- """
- result = client.QueryNodes([], ["name", "bootid"])
- return dict([(name, bootid) for name, bootid in result])
+ client.ArchiveJob(job_id)
+
+ return instances, nodes, smap
class Watcher(object):
- """Encapsulate the logic for restarting erronously halted virtual machines.
+ """Encapsulate the logic for restarting erroneously halted virtual machines.
The calling program should periodically instantiate me and call Run().
This will traverse the list of instances, and make up to MAXTRIES attempts
to restart machines that are down.
"""
- def __init__(self):
- sstore = ssconf.SimpleStore()
- master = sstore.GetMasterNode()
+ def __init__(self, opts, notepad):
+ self.notepad = notepad
+ master = client.QueryConfigValues(["master_node"])[0]
if master != utils.HostInfo().name:
raise NotMasterError("This is not the master node")
- self.instances = GetInstanceList()
- self.bootids = GetNodeBootIDs()
+ # first archive old jobs
+ self.ArchiveJobs(opts.job_age)
+ # and only then submit new ones
+ self.instances, self.bootids, self.smap = GetClusterData()
self.started_instances = set()
+ self.opts = opts
def Run(self):
- notepad = WatcherState()
- try:
- self.CheckInstances(notepad)
- self.CheckDisks(notepad)
- self.VerifyDisks()
- finally:
- notepad.Save()
+ """Watcher run sequence.
+
+ """
+ notepad = self.notepad
+ self.CheckInstances(notepad)
+ self.CheckDisks(notepad)
+ self.VerifyDisks()
+
+ @staticmethod
+ def ArchiveJobs(age):
+ """Archive old jobs.
+
+ """
+ arch_count, left_count = client.AutoArchiveJobs(age)
+ logging.debug("Archived %s jobs, left %s", arch_count, left_count)
def CheckDisks(self, notepad):
"""Check all nodes for restarted ones.
"""
check_nodes = []
- for name, new_id in self.bootids.iteritems():
+ for name, (new_id, offline) in self.bootids.iteritems():
old = notepad.GetNodeBootID(name)
+ if new_id is None:
+ # Bad node, not returning a boot id
+ if not offline:
+ logging.debug("Node %s missing boot id, skipping secondary checks",
+ name)
+ continue
if old != new_id:
# Node's boot ID has changed, proably through a reboot.
check_nodes.append(name)
if check_nodes:
# Activate disks for all instances with any of the checked nodes as a
# secondary node.
- for instance in GetInstanceList(with_secondaries=check_nodes):
- if not instance.autostart:
- logging.info(("Skipping disk activation for non-autostart"
- " instance %s"), instance.name)
- continue
- if instance.name in self.started_instances:
- # we already tried to start the instance, which should have
- # activated its drives (if they can be at all)
+ for node in check_nodes:
+ if node not in self.smap:
continue
- try:
- logging.info("Activating disks for instance %s", instance.name)
- instance.ActivateDisks()
- except Exception:
- logging.exception("Error while activating disks for instance %s",
- instance.name)
+ for instance_name in self.smap[node]:
+ instance = self.instances[instance_name]
+ if not instance.autostart:
+ logging.info(("Skipping disk activation for non-autostart"
+ " instance %s"), instance.name)
+ continue
+ if instance.name in self.started_instances:
+ # we already tried to start the instance, which should have
+ # activated its drives (if they can be at all)
+ continue
+ try:
+ logging.info("Activating disks for instance %s", instance.name)
+ instance.ActivateDisks()
+ except Exception: # pylint: disable-msg=W0703
+ logging.exception("Error while activating disks for instance %s",
+ instance.name)
# Keep changed boot IDs
for name in check_nodes:
- notepad.SetNodeBootID(name, self.bootids[name])
+ notepad.SetNodeBootID(name, self.bootids[name][0])
def CheckInstances(self, notepad):
"""Make a pass over the list of instances, restarting downed ones.
"""
- for instance in self.instances:
+ for instance in self.instances.values():
if instance.state in BAD_STATES:
n = notepad.NumberOfRestartAttempts(instance)
instance.name, last)
instance.Restart()
self.started_instances.add(instance.name)
- except Exception:
- logging.exception("Erro while restarting instance %s", instance.name)
+ except Exception: # pylint: disable-msg=W0703
+ logging.exception("Error while restarting instance %s",
+ instance.name)
notepad.RecordRestartAttempt(instance)
elif instance.state in HELPLESS_STATES:
"""
op = opcodes.OpVerifyDisks()
- result = cli.SubmitOpCode(op, cl=client)
+ job_id = client.SubmitJob([op])
+ result = cli.PollJob(job_id, cl=client, feedback_fn=logging.debug)[0]
+ client.ArchiveJob(job_id)
if not isinstance(result, (tuple, list)):
logging.error("Can't get a valid result from verify-disks")
return
# nothing to do
return
logging.debug("Will activate disks for instances %s",
- ", ".join(offline_disk_instances))
+ utils.CommaJoin(offline_disk_instances))
# we submit only one job, and wait for it. not optimal, but spams
# less the job queue
job = [opcodes.OpActivateInstanceDisks(instance_name=name)
for name in offline_disk_instances]
job_id = cli.SendJob(job, cl=client)
- cli.PollJob(job_id, cl=client, feedback_fn=logging.debug)
+ try:
+ cli.PollJob(job_id, cl=client, feedback_fn=logging.debug)
+ except Exception: # pylint: disable-msg=W0703
+ logging.exception("Error while activating disks")
+
+
+def OpenStateFile(path):
+ """Opens the state file and acquires a lock on it.
+
+ @type path: string
+ @param path: Path to state file
+
+ """
+ # The two-step dance below is necessary to allow both opening existing
+ # file read/write and creating if not existing. Vanilla open will truncate
+ # an existing file -or- allow creating if not existing.
+ statefile_fd = os.open(path, os.O_RDWR | os.O_CREAT)
+
+ # Try to acquire lock on state file. If this fails, another watcher instance
+ # might already be running or another program is temporarily blocking the
+ # watcher from running.
+ try:
+ utils.LockFile(statefile_fd)
+ except errors.LockError, err:
+ logging.error("Can't acquire lock on state file %s: %s", path, err)
+ return None
+
+ return os.fdopen(statefile_fd, "w+")
def ParseOptions():
"""Parse the command line options.
- Returns:
- (options, args) as from OptionParser.parse_args()
+ @return: (options, args) as from OptionParser.parse_args()
"""
parser = OptionParser(description="Ganeti cluster watcher",
version="%%prog (ganeti) %s" %
constants.RELEASE_VERSION)
- parser.add_option("-d", "--debug", dest="debug",
- help="Write all messages to stderr",
- default=False, action="store_true")
+ parser.add_option(cli.DEBUG_OPT)
+ parser.add_option("-A", "--job-age", dest="job_age",
+ help="Autoarchive jobs older than this age (default"
+ " 6 hours)", default=6*3600)
options, args = parser.parse_args()
+ options.job_age = cli.ParseTimespec(options.job_age)
return options, args
"""Main function.
"""
- global client
+ global client # pylint: disable-msg=W0603
options, args = ParseOptions()
- logger.SetupLogging(constants.LOG_WATCHER, debug=options.debug,
- stderr_logging=options.debug)
+ if args: # watcher doesn't take any arguments
+ print >> sys.stderr, ("Usage: %s [-f] " % sys.argv[0])
+ sys.exit(constants.EXIT_FAILURE)
- try:
- client = cli.GetClient()
+ utils.SetupLogging(constants.LOG_WATCHER, debug=options.debug,
+ stderr_logging=options.debug)
+
+ if ShouldPause():
+ logging.debug("Pause has been set, exiting")
+ sys.exit(constants.EXIT_SUCCESS)
+ statefile = OpenStateFile(constants.WATCHER_STATEFILE)
+ if not statefile:
+ sys.exit(constants.EXIT_FAILURE)
+
+ update_file = False
+ try:
+ StartNodeDaemons()
+ RunWatcherHooks()
+ # run node maintenance in all cases, even if master, so that old
+ # masters can be properly cleaned up too
+ if NodeMaintenance.ShouldRun():
+ NodeMaintenance().Exec()
+
+ notepad = WatcherState(statefile)
try:
- watcher = Watcher()
- except errors.ConfigurationError:
- # Just exit if there's no configuration
- sys.exit(constants.EXIT_SUCCESS)
+ try:
+ client = cli.GetClient()
+ except errors.OpPrereqError:
+ # this is, from cli.GetClient, a not-master case
+ logging.debug("Not on master, exiting")
+ update_file = True
+ sys.exit(constants.EXIT_SUCCESS)
+ except luxi.NoMasterError, err:
+ logging.warning("Master seems to be down (%s), trying to restart",
+ str(err))
+ if not utils.EnsureDaemon(constants.MASTERD):
+ logging.critical("Can't start the master, exiting")
+ sys.exit(constants.EXIT_FAILURE)
+ # else retry the connection
+ client = cli.GetClient()
+
+ # we are on master now
+ utils.EnsureDaemon(constants.RAPI)
+
+ try:
+ watcher = Watcher(options, notepad)
+ except errors.ConfigurationError:
+ # Just exit if there's no configuration
+ update_file = True
+ sys.exit(constants.EXIT_SUCCESS)
+
+ watcher.Run()
+ update_file = True
- watcher.Run()
+ finally:
+ if update_file:
+ notepad.Save()
+ else:
+ logging.debug("Not updating status file due to failure")
except SystemExit:
raise
except NotMasterError:
except errors.ResolverError, err:
logging.error("Cannot resolve hostname '%s', exiting.", err.args[0])
sys.exit(constants.EXIT_NODESETUP_ERROR)
+ except errors.JobQueueFull:
+ logging.error("Job queue is full, can't query cluster state")
+ except errors.JobQueueDrainError:
+ logging.error("Job queue is drained, can't maintain cluster state")
except Exception, err:
- logging.error(str(err), exc_info=True)
+ logging.exception(str(err))
sys.exit(constants.EXIT_FAILURE)
projects / ganeti-local / blobdiff