#!/usr/bin/python
#
-# Copyright (C) 2006, 2007, 2008 Google Inc.
+# Copyright (C) 2006, 2007, 2008, 2010 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
# 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 errors
from ganeti import opcodes
from ganeti import cli
+from ganeti import luxi
+from ganeti import ssconf
+from ganeti import bdev
+from ganeti import hypervisor
+from ganeti import rapi
+from ganeti.confd import client as confd_client
+from ganeti import netutils
+
+import ganeti.rapi.client # pylint: disable-msg=W0611
MAXTRIES = 5
+# Delete any record that is older than 8 hours; this value is based on
+# the fact that the current retry counter is 5, and watcher runs every
+# 5 minutes, so it takes around half an hour to exceed the retry
+# counter, so 8 hours (16*1/2h) seems like a reasonable reset time
+RETRY_EXPIRATION = 8 * 3600
BAD_STATES = ['ERROR_down']
HELPLESS_STATES = ['ERROR_nodedown', 'ERROR_nodeoffline']
NOTICE = 'NOTICE'
"""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)
+
+
+def RunWatcherHooks():
+ """Run the watcher hooks.
+
+ """
+ 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)
+
- @param s: the string to indent
- @param prefix: the string to prepend each line
+class NodeMaintenance(object):
+ """Talks to confd daemons and possible shutdown instances/drbd devices.
"""
- return "%s%s\n" % (prefix, ('\n' + prefix).join(s.splitlines()))
+ 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 = netutils.Hostname.GetSysName()
+ 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:
return 0
+ def MaintainInstanceList(self, instances):
+ """Perform maintenance on the recorded instances.
+
+ @type instances: list of string
+ @param instances: the list of currently existing instances
+
+ """
+ idict = self._data["instance"]
+ # First, delete obsolete instances
+ obsolete_instances = set(idict).difference(instances)
+ for inst in obsolete_instances:
+ logging.debug("Forgetting obsolete instance %s", inst)
+ del idict[inst]
+
+ # Second, delete expired records
+ earliest = time.time() - RETRY_EXPIRATION
+ expired_instances = [i for i in idict
+ if idict[i][KEY_RESTART_WHEN] < earliest]
+ for inst in expired_instances:
+ logging.debug("Expiring record for instance %s", inst)
+ del idict[inst]
+
def RecordRestartAttempt(self, instance):
"""Record a restart attempt.
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, True)
+ 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)
+
+ for fields in result:
+ (name, status, autostart, snodes) = fields
- instances.append(Instance(name, status, autostart))
+ # update the secondary node map
+ for node in snodes:
+ if node not in smap:
+ smap[node] = []
+ smap[node].append(name)
- return instances
+ instances[name] = Instance(name, status, autostart)
+ nodes = dict([(name, (bootid, offline))
+ for name, bootid, offline in all_results[1]])
-def GetNodeBootIDs():
- """Get a dict mapping nodes to boot IDs.
+ client.ArchiveJob(job_id)
- """
- result = client.QueryNodes([], ["name", "bootid", "offline"], True)
- return dict([(name, (bootid, offline)) for name, bootid, offline in result])
+ 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, opts):
+ def __init__(self, opts, notepad):
+ self.notepad = notepad
master = client.QueryConfigValues(["master_node"])[0]
- if master != utils.HostInfo().name:
+ if master != netutils.Hostname.GetSysName():
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.ArchiveJobs(self.opts.job_age)
- 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()
- def ArchiveJobs(self, age):
+ @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))
+ logging.debug("Archived %s jobs, left %s", arch_count, left_count)
def CheckDisks(self, notepad):
"""Check all nodes for restarted ones.
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:
"""Make a pass over the list of instances, restarting downed ones.
"""
- for instance in self.instances:
+ notepad.MaintainInstanceList(self.instances.keys())
+
+ for instance in self.instances.values():
if instance.state in BAD_STATES:
n = notepad.NumberOfRestartAttempts(instance)
if n > MAXTRIES:
- # stay quiet.
+ logging.warning("Not restarting instance %s, retries exhausted",
+ instance.name)
continue
elif n < MAXTRIES:
last = " (Attempt #%d)" % (n + 1)
instance.name, last)
instance.Restart()
self.started_instances.add(instance.name)
- except Exception:
+ except Exception: # pylint: disable-msg=W0703
logging.exception("Error while restarting instance %s",
instance.name)
"""
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 IsRapiResponding(hostname):
+ """Connects to RAPI port and does a simple test.
+
+ Connects to RAPI port of hostname and does a simple test. At this time, the
+ test is GetVersion.
+
+ @type hostname: string
+ @param hostname: hostname of the node to connect to.
+ @rtype: bool
+ @return: Whether RAPI is working properly
+
+ """
+ curl_config = rapi.client.GenericCurlConfig(cafile=constants.RAPI_CERT_FILE)
+ rapi_client = rapi.client.GanetiRapiClient(hostname,
+ curl_config_fn=curl_config)
+ try:
+ master_version = rapi_client.GetVersion()
+ except rapi.client.CertificateError, err:
+ logging.warning("RAPI Error: CertificateError (%s)", err)
+ return False
+ except rapi.client.GanetiApiError, err:
+ logging.warning("RAPI Error: GanetiApiError (%s)", err)
+ return False
+ logging.debug("RAPI Result: master_version is %s", master_version)
+ return master_version == constants.RAPI_VERSION
def ParseOptions():
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)
return options, args
+@rapi.client.UsesRapiClient
def main():
"""Main function.
"""
- global client
+ global client # pylint: disable-msg=W0603
options, args = ParseOptions()
+ if args: # watcher doesn't take any arguments
+ print >> sys.stderr, ("Usage: %s [-f] " % sys.argv[0])
+ sys.exit(constants.EXIT_FAILURE)
+
utils.SetupLogging(constants.LOG_WATCHER, debug=options.debug,
stderr_logging=options.debug)
- try:
- client = cli.GetClient()
+ 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(options)
- 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)
+
+ # If RAPI isn't responding to queries, try one restart.
+ logging.debug("Attempting to talk with RAPI.")
+ if not IsRapiResponding(constants.IP4_ADDRESS_LOCALHOST):
+ logging.warning("Couldn't get answer from Ganeti RAPI daemon."
+ " Restarting Ganeti RAPI.")
+ utils.StopDaemon(constants.RAPI)
+ utils.EnsureDaemon(constants.RAPI)
+ logging.debug("Second attempt to talk with RAPI")
+ if not IsRapiResponding(constants.IP4_ADDRESS_LOCALHOST):
+ logging.fatal("RAPI is not responding. Please investigate.")
+ logging.debug("Successfully talked to 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