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+      #
+      #
       # Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 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.
       """Configuration management for Ganeti
       This module provides the interface to the Ganeti cluster configuration.
       The configuration data is stored on every node but is updated on the master
       only. After each update, the master distributes the data to the other nodes.
       Currently, the data storage format is JSON. YAML was slow and consuming too
       much memory.
       """
       # pylint: disable=R0904
       # R0904: Too many public methods
       import os
       import random
       import logging
       import time
       import itertools
       from ganeti import errors
       from ganeti import locking
       from ganeti import utils
       from ganeti import constants
       from ganeti import rpc
       from ganeti import objects
       from ganeti import serializer
       from ganeti import uidpool
       from ganeti import netutils
       from ganeti import runtime
       _config_lock = locking.SharedLock("ConfigWriter")
       # job id used for resource management at config upgrade time
       _UPGRADE_CONFIG_JID = "jid-cfg-upgrade"
       def _ValidateConfig(data):
         """Verifies that a configuration objects looks valid.
         This only verifies the version of the configuration.
         @raise errors.ConfigurationError: if the version differs from what
             we expect
         """
         if data.version != constants.CONFIG_VERSION:
           raise errors.ConfigVersionMismatch(constants.CONFIG_VERSION, data.version)
       class TemporaryReservationManager:
         """A temporary resource reservation manager.
         This is used to reserve resources in a job, before using them, making sure
         other jobs cannot get them in the meantime.
         """
         def __init__(self):
           self._ec_reserved = {}
         def Reserved(self, resource):
           for holder_reserved in self._ec_reserved.values():
             if resource in holder_reserved:
               return True
           return False
         def Reserve(self, ec_id, resource):
           if self.Reserved(resource):
             raise errors.ReservationError("Duplicate reservation for resource '%s'"
                                           % str(resource))
           if ec_id not in self._ec_reserved:
             self._ec_reserved[ec_id] = set([resource])
           else:
             self._ec_reserved[ec_id].add(resource)
         def DropECReservations(self, ec_id):
           if ec_id in self._ec_reserved:
             del self._ec_reserved[ec_id]
         def GetReserved(self):
           all_reserved = set()
           for holder_reserved in self._ec_reserved.values():
             all_reserved.update(holder_reserved)
           return all_reserved
         def Generate(self, existing, generate_one_fn, ec_id):
           """Generate a new resource of this type
           """
           assert callable(generate_one_fn)
           all_elems = self.GetReserved()
           all_elems.update(existing)
           retries = 64
           while retries > 0:
             new_resource = generate_one_fn()
             if new_resource is not None and new_resource not in all_elems:
               break
           else:
             raise errors.ConfigurationError("Not able generate new resource"
                                             " (last tried: %s)" % new_resource)
           self.Reserve(ec_id, new_resource)
           return new_resource
       def _MatchNameComponentIgnoreCase(short_name, names):
         """Wrapper around L{utils.text.MatchNameComponent}.
         """
         return utils.MatchNameComponent(short_name, names, case_sensitive=False)
       def _CheckInstanceDiskIvNames(disks):
         """Checks if instance's disks' C{iv_name} attributes are in order.
         @type disks: list of L{objects.Disk}
         @param disks: List of disks
         @rtype: list of tuples; (int, string, string)
         @return: List of wrongly named disks, each tuple contains disk index,
           expected and actual name
         """
         result = []
         for (idx, disk) in enumerate(disks):
           exp_iv_name = "disk/%s" % idx
           if disk.iv_name != exp_iv_name:
             result.append((idx, exp_iv_name, disk.iv_name))
         return result
       class ConfigWriter:
         """The interface to the cluster configuration.
         @ivar _temporary_lvs: reservation manager for temporary LVs
         @ivar _all_rms: a list of all temporary reservation managers
         """
         def __init__(self, cfg_file=None, offline=False, _getents=runtime.GetEnts,
                      accept_foreign=False):
           self.write_count = 0
           self._lock = _config_lock
           self._config_data = None
           self._offline = offline
           if cfg_file is None:
             self._cfg_file = constants.CLUSTER_CONF_FILE
           else:
             self._cfg_file = cfg_file
           self._getents = _getents
           self._temporary_ids = TemporaryReservationManager()
           self._temporary_drbds = {}
           self._temporary_macs = TemporaryReservationManager()
           self._temporary_secrets = TemporaryReservationManager()
           self._temporary_lvs = TemporaryReservationManager()
           self._all_rms = [self._temporary_ids, self._temporary_macs,
                            self._temporary_secrets, self._temporary_lvs]
           # Note: in order to prevent errors when resolving our name in
           # _DistributeConfig, we compute it here once and reuse it; it's
           # better to raise an error before starting to modify the config
           # file than after it was modified
           self._my_hostname = netutils.Hostname.GetSysName()
           self._last_cluster_serial = -1
           self._cfg_id = None
           self._context = None
           self._OpenConfig(accept_foreign)
         def _GetRpc(self, address_list):
           """Returns RPC runner for configuration.
           """
           return rpc.ConfigRunner(self._context, address_list)
         def SetContext(self, context):
           """Sets Ganeti context.
           """
           self._context = context
         # this method needs to be static, so that we can call it on the class
         @staticmethod
         def IsCluster():
           """Check if the cluster is configured.
           """
           return os.path.exists(constants.CLUSTER_CONF_FILE)
         def _GenerateOneMAC(self):
           """Generate one mac address
           """
           prefix = self._config_data.cluster.mac_prefix
           byte1 = random.randrange(0, 256)
           byte2 = random.randrange(0, 256)
           byte3 = random.randrange(0, 256)
           mac = "%s:%02x:%02x:%02x" % (prefix, byte1, byte2, byte3)
           return mac
         @locking.ssynchronized(_config_lock, shared=1)
         def GetNdParams(self, node):
           """Get the node params populated with cluster defaults.
           @type node: L{objects.Node}
           @param node: The node we want to know the params for
           @return: A dict with the filled in node params
           """
           nodegroup = self._UnlockedGetNodeGroup(node.group)
           return self._config_data.cluster.FillND(node, nodegroup)
         @locking.ssynchronized(_config_lock, shared=1)
         def GenerateMAC(self, ec_id):
           """Generate a MAC for an instance.
           This should check the current instances for duplicates.
           """
           existing = self._AllMACs()
           return self._temporary_ids.Generate(existing, self._GenerateOneMAC, ec_id)
         @locking.ssynchronized(_config_lock, shared=1)
         def ReserveMAC(self, mac, ec_id):
           """Reserve a MAC for an instance.
           This only checks instances managed by this cluster, it does not
           check for potential collisions elsewhere.
           """
           all_macs = self._AllMACs()
           if mac in all_macs:
             raise errors.ReservationError("mac already in use")
           else:
             self._temporary_macs.Reserve(ec_id, mac)
         @locking.ssynchronized(_config_lock, shared=1)
         def ReserveLV(self, lv_name, ec_id):
           """Reserve an VG/LV pair for an instance.
           @type lv_name: string
           @param lv_name: the logical volume name to reserve
           """
           all_lvs = self._AllLVs()
           if lv_name in all_lvs:
             raise errors.ReservationError("LV already in use")
           else:
             self._temporary_lvs.Reserve(ec_id, lv_name)
         @locking.ssynchronized(_config_lock, shared=1)
         def GenerateDRBDSecret(self, ec_id):
           """Generate a DRBD secret.
           This checks the current disks for duplicates.
           """
           return self._temporary_secrets.Generate(self._AllDRBDSecrets(),
                                                   utils.GenerateSecret,
                                                   ec_id)
         def _AllLVs(self):
           """Compute the list of all LVs.
           """
           lvnames = set()
           for instance in self._config_data.instances.values():
             node_data = instance.MapLVsByNode()
             for lv_list in node_data.values():
               lvnames.update(lv_list)
           return lvnames
         def _AllIDs(self, include_temporary):
           """Compute the list of all UUIDs and names we have.
           @type include_temporary: boolean
           @param include_temporary: whether to include the _temporary_ids set
           @rtype: set
           @return: a set of IDs
           """
           existing = set()
           if include_temporary:
             existing.update(self._temporary_ids.GetReserved())
           existing.update(self._AllLVs())
           existing.update(self._config_data.instances.keys())
           existing.update(self._config_data.nodes.keys())
           existing.update([i.uuid for i in self._AllUUIDObjects() if i.uuid])
           return existing
         def _GenerateUniqueID(self, ec_id):
           """Generate an unique UUID.
           This checks the current node, instances and disk names for
           duplicates.
           @rtype: string
           @return: the unique id
           """
           existing = self._AllIDs(include_temporary=False)
           return self._temporary_ids.Generate(existing, utils.NewUUID, ec_id)
         @locking.ssynchronized(_config_lock, shared=1)
         def GenerateUniqueID(self, ec_id):
           """Generate an unique ID.
           This is just a wrapper over the unlocked version.
           @type ec_id: string
           @param ec_id: unique id for the job to reserve the id to
           """
           return self._GenerateUniqueID(ec_id)
         def _AllMACs(self):
           """Return all MACs present in the config.
           @rtype: list
           @return: the list of all MACs
           """
           result = []
           for instance in self._config_data.instances.values():
             for nic in instance.nics:
               result.append(nic.mac)
           return result
         def _AllDRBDSecrets(self):
           """Return all DRBD secrets present in the config.
           @rtype: list
           @return: the list of all DRBD secrets
           """
           def helper(disk, result):
             """Recursively gather secrets from this disk."""
             if disk.dev_type == constants.DT_DRBD8:
               result.append(disk.logical_id[5])
             if disk.children:
               for child in disk.children:
                 helper(child, result)
           result = []
           for instance in self._config_data.instances.values():
             for disk in instance.disks:
               helper(disk, result)
           return result
         def _CheckDiskIDs(self, disk, l_ids, p_ids):
           """Compute duplicate disk IDs
           @type disk: L{objects.Disk}
           @param disk: the disk at which to start searching
           @type l_ids: list
           @param l_ids: list of current logical ids
           @type p_ids: list
           @param p_ids: list of current physical ids
           @rtype: list
           @return: a list of error messages
           """
           result = []
           if disk.logical_id is not None:
             if disk.logical_id in l_ids:
               result.append("duplicate logical id %s" % str(disk.logical_id))
             else:
               l_ids.append(disk.logical_id)
           if disk.physical_id is not None:
             if disk.physical_id in p_ids:
               result.append("duplicate physical id %s" % str(disk.physical_id))
             else:
               p_ids.append(disk.physical_id)
           if disk.children:
             for child in disk.children:
               result.extend(self._CheckDiskIDs(child, l_ids, p_ids))
           return result
         def _UnlockedVerifyConfig(self):
           """Verify function.
           @rtype: list
           @return: a list of error messages; a non-empty list signifies
               configuration errors
           """
           # pylint: disable=R0914
           result = []
           seen_macs = []
           ports = {}
           data = self._config_data
           cluster = data.cluster
           seen_lids = []
           seen_pids = []
           # global cluster checks
           if not cluster.enabled_hypervisors:
             result.append("enabled hypervisors list doesn't have any entries")
           invalid_hvs = set(cluster.enabled_hypervisors) - constants.HYPER_TYPES
           if invalid_hvs:
             result.append("enabled hypervisors contains invalid entries: %s" %
                           invalid_hvs)
           missing_hvp = (set(cluster.enabled_hypervisors) -
                          set(cluster.hvparams.keys()))
           if missing_hvp:
             result.append("hypervisor parameters missing for the enabled"
                           " hypervisor(s) %s" % utils.CommaJoin(missing_hvp))
           if cluster.master_node not in data.nodes:
             result.append("cluster has invalid primary node '%s'" %
                           cluster.master_node)
           def _helper(owner, attr, value, template):
             try:
               utils.ForceDictType(value, template)
             except errors.GenericError, err:
               result.append("%s has invalid %s: %s" % (owner, attr, err))
           def _helper_nic(owner, params):
             try:
               objects.NIC.CheckParameterSyntax(params)
             except errors.ConfigurationError, err:
               result.append("%s has invalid nicparams: %s" % (owner, err))
           def _helper_ipolicy(owner, params):
             try:
               objects.InstancePolicy.CheckParameterSyntax(params)
             except errors.ConfigurationError, err:
               result.append("%s has invalid instance policy: %s" % (owner, err))
           def _helper_ispecs(owner, params):
             for key, value in params.items():
               if key in constants.IPOLICY_ISPECS:
                 fullkey = "ipolicy/" + key
                 _helper(owner, fullkey, value, constants.ISPECS_PARAMETER_TYPES)
               else:
                 # FIXME: assuming list type
                 if key in constants.IPOLICY_PARAMETERS:
                   exp_type = float
                 else:
                   exp_type = list
                 if not isinstance(value, exp_type):
                   result.append("%s has invalid instance policy: for %s,"
                                 " expecting %s, got %s" %
                                 (owner, key, exp_type.__name__, type(value)))
           # check cluster parameters
           _helper("cluster", "beparams", cluster.SimpleFillBE({}),
                   constants.BES_PARAMETER_TYPES)
           _helper("cluster", "nicparams", cluster.SimpleFillNIC({}),
                   constants.NICS_PARAMETER_TYPES)
           _helper_nic("cluster", cluster.SimpleFillNIC({}))
           _helper("cluster", "ndparams", cluster.SimpleFillND({}),
                   constants.NDS_PARAMETER_TYPES)
           _helper_ipolicy("cluster", cluster.SimpleFillIPolicy({}))
           _helper_ispecs("cluster", cluster.SimpleFillIPolicy({}))
           # per-instance checks
           for instance_name in data.instances:
             instance = data.instances[instance_name]
             if instance.name != instance_name:
               result.append("instance '%s' is indexed by wrong name '%s'" %
                             (instance.name, instance_name))
             if instance.primary_node not in data.nodes:
               result.append("instance '%s' has invalid primary node '%s'" %
                             (instance_name, instance.primary_node))
             for snode in instance.secondary_nodes:
               if snode not in data.nodes:
                 result.append("instance '%s' has invalid secondary node '%s'" %
                               (instance_name, snode))
             for idx, nic in enumerate(instance.nics):
               if nic.mac in seen_macs:
                 result.append("instance '%s' has NIC %d mac %s duplicate" %
                               (instance_name, idx, nic.mac))
               else:
                 seen_macs.append(nic.mac)
               if nic.nicparams:
                 filled = cluster.SimpleFillNIC(nic.nicparams)
                 owner = "instance %s nic %d" % (instance.name, idx)
                 _helper(owner, "nicparams",
                         filled, constants.NICS_PARAMETER_TYPES)
                 _helper_nic(owner, filled)
             # parameter checks
             if instance.beparams:
               _helper("instance %s" % instance.name, "beparams",
                       cluster.FillBE(instance), constants.BES_PARAMETER_TYPES)
             # gather the drbd ports for duplicate checks
             for (idx, dsk) in enumerate(instance.disks):
               if dsk.dev_type in constants.LDS_DRBD:
                 tcp_port = dsk.logical_id[2]
                 if tcp_port not in ports:
                   ports[tcp_port] = []
                 ports[tcp_port].append((instance.name, "drbd disk %s" % idx))
             # gather network port reservation
             net_port = getattr(instance, "network_port", None)
             if net_port is not None:
               if net_port not in ports:
                 ports[net_port] = []
               ports[net_port].append((instance.name, "network port"))
             # instance disk verify
             for idx, disk in enumerate(instance.disks):
               result.extend(["instance '%s' disk %d error: %s" %
                              (instance.name, idx, msg) for msg in disk.Verify()])
               result.extend(self._CheckDiskIDs(disk, seen_lids, seen_pids))
             wrong_names = _CheckInstanceDiskIvNames(instance.disks)
             if wrong_names:
               tmp = "; ".join(("name of disk %s should be '%s', but is '%s'" %
                                (idx, exp_name, actual_name))
                               for (idx, exp_name, actual_name) in wrong_names)
               result.append("Instance '%s' has wrongly named disks: %s" %
                             (instance.name, tmp))
           # cluster-wide pool of free ports
           for free_port in cluster.tcpudp_port_pool:
             if free_port not in ports:
               ports[free_port] = []
             ports[free_port].append(("cluster", "port marked as free"))
           # compute tcp/udp duplicate ports
           keys = ports.keys()
           keys.sort()
           for pnum in keys:
             pdata = ports[pnum]
             if len(pdata) > 1:
               txt = utils.CommaJoin(["%s/%s" % val for val in pdata])
               result.append("tcp/udp port %s has duplicates: %s" % (pnum, txt))
           # highest used tcp port check
           if keys:
             if keys[-1] > cluster.highest_used_port:
               result.append("Highest used port mismatch, saved %s, computed %s" %
                             (cluster.highest_used_port, keys[-1]))
           if not data.nodes[cluster.master_node].master_candidate:
             result.append("Master node is not a master candidate")
           # master candidate checks
           mc_now, mc_max, _ = self._UnlockedGetMasterCandidateStats()
           if mc_now < mc_max:
             result.append("Not enough master candidates: actual %d, target %d" %
                           (mc_now, mc_max))
           # node checks
           for node_name, node in data.nodes.items():
             if node.name != node_name:
               result.append("Node '%s' is indexed by wrong name '%s'" %
                             (node.name, node_name))
             if [node.master_candidate, node.drained, node.offline].count(True) > 1:
               result.append("Node %s state is invalid: master_candidate=%s,"
                             " drain=%s, offline=%s" %
                             (node.name, node.master_candidate, node.drained,
                              node.offline))
             if node.group not in data.nodegroups:
               result.append("Node '%s' has invalid group '%s'" %
                             (node.name, node.group))
             else:
               _helper("node %s" % node.name, "ndparams",
                       cluster.FillND(node, data.nodegroups[node.group]),
                       constants.NDS_PARAMETER_TYPES)
           # nodegroups checks
           nodegroups_names = set()
           for nodegroup_uuid in data.nodegroups:
             nodegroup = data.nodegroups[nodegroup_uuid]
             if nodegroup.uuid != nodegroup_uuid:
               result.append("node group '%s' (uuid: '%s') indexed by wrong uuid '%s'"
                             % (nodegroup.name, nodegroup.uuid, nodegroup_uuid))
             if utils.UUID_RE.match(nodegroup.name.lower()):
               result.append("node group '%s' (uuid: '%s') has uuid-like name" %
                             (nodegroup.name, nodegroup.uuid))
             if nodegroup.name in nodegroups_names:
               result.append("duplicate node group name '%s'" % nodegroup.name)
             else:
               nodegroups_names.add(nodegroup.name)
             group_name = "group %s" % nodegroup.name
             _helper_ipolicy(group_name, cluster.SimpleFillIPolicy(nodegroup.ipolicy))
             _helper_ispecs(group_name, cluster.SimpleFillIPolicy(nodegroup.ipolicy))
             if nodegroup.ndparams:
               _helper(group_name, "ndparams",
                       cluster.SimpleFillND(nodegroup.ndparams),
                       constants.NDS_PARAMETER_TYPES)
           # drbd minors check
           _, duplicates = self._UnlockedComputeDRBDMap()
           for node, minor, instance_a, instance_b in duplicates:
             result.append("DRBD minor %d on node %s is assigned twice to instances"
                           " %s and %s" % (minor, node, instance_a, instance_b))
           # IP checks
           default_nicparams = cluster.nicparams[constants.PP_DEFAULT]
           ips = {}
           def _AddIpAddress(ip, name):
             ips.setdefault(ip, []).append(name)
           _AddIpAddress(cluster.master_ip, "cluster_ip")
           for node in data.nodes.values():
             _AddIpAddress(node.primary_ip, "node:%s/primary" % node.name)
             if node.secondary_ip != node.primary_ip:
               _AddIpAddress(node.secondary_ip, "node:%s/secondary" % node.name)
           for instance in data.instances.values():
             for idx, nic in enumerate(instance.nics):
               if nic.ip is None:
                 continue
               nicparams = objects.FillDict(default_nicparams, nic.nicparams)
               nic_mode = nicparams[constants.NIC_MODE]
               nic_link = nicparams[constants.NIC_LINK]
               if nic_mode == constants.NIC_MODE_BRIDGED:
                 link = "bridge:%s" % nic_link
               elif nic_mode == constants.NIC_MODE_ROUTED:
                 link = "route:%s" % nic_link
               else:
                 raise errors.ProgrammerError("NIC mode '%s' not handled" % nic_mode)
               _AddIpAddress("%s/%s" % (link, nic.ip),
                             "instance:%s/nic:%d" % (instance.name, idx))
           for ip, owners in ips.items():
             if len(owners) > 1:
               result.append("IP address %s is used by multiple owners: %s" %
                             (ip, utils.CommaJoin(owners)))
           return result
         @locking.ssynchronized(_config_lock, shared=1)
         def VerifyConfig(self):
           """Verify function.
           This is just a wrapper over L{_UnlockedVerifyConfig}.
           @rtype: list
           @return: a list of error messages; a non-empty list signifies
               configuration errors
           """
           return self._UnlockedVerifyConfig()
         def _UnlockedSetDiskID(self, disk, node_name):
           """Convert the unique ID to the ID needed on the target nodes.
           This is used only for drbd, which needs ip/port configuration.
           The routine descends down and updates its children also, because
           this helps when the only the top device is passed to the remote
           node.
           This function is for internal use, when the config lock is already held.
           """
           if disk.children:
             for child in disk.children:
               self._UnlockedSetDiskID(child, node_name)
           if disk.logical_id is None and disk.physical_id is not None:
             return
           if disk.dev_type == constants.LD_DRBD8:
             pnode, snode, port, pminor, sminor, secret = disk.logical_id
             if node_name not in (pnode, snode):
               raise errors.ConfigurationError("DRBD device not knowing node %s" %
                                               node_name)
             pnode_info = self._UnlockedGetNodeInfo(pnode)
             snode_info = self._UnlockedGetNodeInfo(snode)
             if pnode_info is None or snode_info is None:
               raise errors.ConfigurationError("Can't find primary or secondary node"
                                               " for %s" % str(disk))
             p_data = (pnode_info.secondary_ip, port)
             s_data = (snode_info.secondary_ip, port)
             if pnode == node_name:
               disk.physical_id = p_data + s_data + (pminor, secret)
             else: # it must be secondary, we tested above
               disk.physical_id = s_data + p_data + (sminor, secret)
           else:
             disk.physical_id = disk.logical_id
           return
         @locking.ssynchronized(_config_lock)
         def SetDiskID(self, disk, node_name):
           """Convert the unique ID to the ID needed on the target nodes.
           This is used only for drbd, which needs ip/port configuration.
           The routine descends down and updates its children also, because
           this helps when the only the top device is passed to the remote
           node.
           """
           return self._UnlockedSetDiskID(disk, node_name)
         @locking.ssynchronized(_config_lock)
         def AddTcpUdpPort(self, port):
           """Adds a new port to the available port pool.
           """
           if not isinstance(port, int):
             raise errors.ProgrammerError("Invalid type passed for port")
           self._config_data.cluster.tcpudp_port_pool.add(port)
           self._WriteConfig()
         @locking.ssynchronized(_config_lock, shared=1)
         def GetPortList(self):
           """Returns a copy of the current port list.
           """
           return self._config_data.cluster.tcpudp_port_pool.copy()
         @locking.ssynchronized(_config_lock)
         def AllocatePort(self):
           """Allocate a port.
           The port will be taken from the available port pool or from the
           default port range (and in this case we increase
           highest_used_port).
           """
           # If there are TCP/IP ports configured, we use them first.
           if self._config_data.cluster.tcpudp_port_pool:
             port = self._config_data.cluster.tcpudp_port_pool.pop()
           else:
             port = self._config_data.cluster.highest_used_port + 1
             if port >= constants.LAST_DRBD_PORT:
               raise errors.ConfigurationError("The highest used port is greater"
                                               " than %s. Aborting." %
                                               constants.LAST_DRBD_PORT)
             self._config_data.cluster.highest_used_port = port
           self._WriteConfig()
           return port
         def _UnlockedComputeDRBDMap(self):
           """Compute the used DRBD minor/nodes.
           @rtype: (dict, list)
           @return: dictionary of node_name: dict of minor: instance_name;
               the returned dict will have all the nodes in it (even if with
               an empty list), and a list of duplicates; if the duplicates
               list is not empty, the configuration is corrupted and its caller
               should raise an exception
           """
           def _AppendUsedPorts(instance_name, disk, used):
             duplicates = []
             if disk.dev_type == constants.LD_DRBD8 and len(disk.logical_id) >= 5:
               node_a, node_b, _, minor_a, minor_b = disk.logical_id[:5]
               for node, port in ((node_a, minor_a), (node_b, minor_b)):
                 assert node in used, ("Node '%s' of instance '%s' not found"
                                       " in node list" % (node, instance_name))
                 if port in used[node]:
                   duplicates.append((node, port, instance_name, used[node][port]))
                 else:
                   used[node][port] = instance_name
             if disk.children:
               for child in disk.children:
                 duplicates.extend(_AppendUsedPorts(instance_name, child, used))
             return duplicates
           duplicates = []
           my_dict = dict((node, {}) for node in self._config_data.nodes)
           for instance in self._config_data.instances.itervalues():
             for disk in instance.disks:
               duplicates.extend(_AppendUsedPorts(instance.name, disk, my_dict))
           for (node, minor), instance in self._temporary_drbds.iteritems():
             if minor in my_dict[node] and my_dict[node][minor] != instance:
               duplicates.append((node, minor, instance, my_dict[node][minor]))
             else:
               my_dict[node][minor] = instance
           return my_dict, duplicates
         @locking.ssynchronized(_config_lock)
         def ComputeDRBDMap(self):
           """Compute the used DRBD minor/nodes.
           This is just a wrapper over L{_UnlockedComputeDRBDMap}.
           @return: dictionary of node_name: dict of minor: instance_name;
               the returned dict will have all the nodes in it (even if with
               an empty list).
           """
           d_map, duplicates = self._UnlockedComputeDRBDMap()
           if duplicates:
             raise errors.ConfigurationError("Duplicate DRBD ports detected: %s" %
                                             str(duplicates))
           return d_map
         @locking.ssynchronized(_config_lock)
         def AllocateDRBDMinor(self, nodes, instance):
           """Allocate a drbd minor.
           The free minor will be automatically computed from the existing
           devices. A node can be given multiple times in order to allocate
           multiple minors. The result is the list of minors, in the same
           order as the passed nodes.
           @type instance: string
           @param instance: the instance for which we allocate minors
           """
           assert isinstance(instance, basestring), \
                  "Invalid argument '%s' passed to AllocateDRBDMinor" % instance
           d_map, duplicates = self._UnlockedComputeDRBDMap()
           if duplicates:
             raise errors.ConfigurationError("Duplicate DRBD ports detected: %s" %
                                             str(duplicates))
           result = []
           for nname in nodes:
             ndata = d_map[nname]
             if not ndata:
               # no minors used, we can start at 0
               result.append(0)
               ndata[0] = instance
               self._temporary_drbds[(nname, 0)] = instance
               continue
             keys = ndata.keys()
             keys.sort()
             ffree = utils.FirstFree(keys)
             if ffree is None:
               # return the next minor
               # TODO: implement high-limit check
               minor = keys[-1] + 1
             else:
               minor = ffree
             # double-check minor against current instances
             assert minor not in d_map[nname], \
                    ("Attempt to reuse allocated DRBD minor %d on node %s,"
                     " already allocated to instance %s" %
                     (minor, nname, d_map[nname][minor]))
             ndata[minor] = instance
             # double-check minor against reservation
             r_key = (nname, minor)
             assert r_key not in self._temporary_drbds, \
                    ("Attempt to reuse reserved DRBD minor %d on node %s,"
                     " reserved for instance %s" %
                     (minor, nname, self._temporary_drbds[r_key]))
             self._temporary_drbds[r_key] = instance
             result.append(minor)
           logging.debug("Request to allocate drbd minors, input: %s, returning %s",
                         nodes, result)
           return result
         def _UnlockedReleaseDRBDMinors(self, instance):
           """Release temporary drbd minors allocated for a given instance.
           @type instance: string
           @param instance: the instance for which temporary minors should be
                            released
           """
           assert isinstance(instance, basestring), \
                  "Invalid argument passed to ReleaseDRBDMinors"
           for key, name in self._temporary_drbds.items():
             if name == instance:
               del self._temporary_drbds[key]
         @locking.ssynchronized(_config_lock)
         def ReleaseDRBDMinors(self, instance):
           """Release temporary drbd minors allocated for a given instance.
           This should be called on the error paths, on the success paths
           it's automatically called by the ConfigWriter add and update
           functions.
           This function is just a wrapper over L{_UnlockedReleaseDRBDMinors}.
           @type instance: string
           @param instance: the instance for which temporary minors should be
                            released
           """
           self._UnlockedReleaseDRBDMinors(instance)
         @locking.ssynchronized(_config_lock, shared=1)
         def GetConfigVersion(self):
           """Get the configuration version.
           @return: Config version
           """
           return self._config_data.version
         @locking.ssynchronized(_config_lock, shared=1)
         def GetClusterName(self):
           """Get cluster name.
           @return: Cluster name
           """
           return self._config_data.cluster.cluster_name
         @locking.ssynchronized(_config_lock, shared=1)
         def GetMasterNode(self):
           """Get the hostname of the master node for this cluster.
           @return: Master hostname
           """
           return self._config_data.cluster.master_node
         @locking.ssynchronized(_config_lock, shared=1)
         def GetMasterIP(self):
           """Get the IP of the master node for this cluster.
           @return: Master IP
           """
           return self._config_data.cluster.master_ip
         @locking.ssynchronized(_config_lock, shared=1)
         def GetMasterNetdev(self):
           """Get the master network device for this cluster.
           """
           return self._config_data.cluster.master_netdev
         @locking.ssynchronized(_config_lock, shared=1)
         def GetMasterNetmask(self):
           """Get the netmask of the master node for this cluster.
           """
           return self._config_data.cluster.master_netmask
         @locking.ssynchronized(_config_lock, shared=1)
         def GetUseExternalMipScript(self):
           """Get flag representing whether to use the external master IP setup script.
           """
           return self._config_data.cluster.use_external_mip_script
         @locking.ssynchronized(_config_lock, shared=1)
         def GetFileStorageDir(self):
           """Get the file storage dir for this cluster.
           """
           return self._config_data.cluster.file_storage_dir
         @locking.ssynchronized(_config_lock, shared=1)
         def GetSharedFileStorageDir(self):
           """Get the shared file storage dir for this cluster.
           """
           return self._config_data.cluster.shared_file_storage_dir
         @locking.ssynchronized(_config_lock, shared=1)
         def GetHypervisorType(self):
           """Get the hypervisor type for this cluster.
           """
           return self._config_data.cluster.enabled_hypervisors[0]
         @locking.ssynchronized(_config_lock, shared=1)
         def GetHostKey(self):
           """Return the rsa hostkey from the config.
           @rtype: string
           @return: the rsa hostkey
           """
           return self._config_data.cluster.rsahostkeypub
         @locking.ssynchronized(_config_lock, shared=1)
         def GetDefaultIAllocator(self):
           """Get the default instance allocator for this cluster.
           """
           return self._config_data.cluster.default_iallocator
         @locking.ssynchronized(_config_lock, shared=1)
         def GetPrimaryIPFamily(self):
           """Get cluster primary ip family.
           @return: primary ip family
           """
           return self._config_data.cluster.primary_ip_family
         @locking.ssynchronized(_config_lock, shared=1)
         def GetMasterNetworkParameters(self):
           """Get network parameters of the master node.
           @rtype: L{object.MasterNetworkParameters}
           @return: network parameters of the master node
           """
           cluster = self._config_data.cluster
           result = objects.MasterNetworkParameters(name=cluster.master_node,
             ip=cluster.master_ip,
             netmask=cluster.master_netmask,
             netdev=cluster.master_netdev,
             ip_family=cluster.primary_ip_family)
           return result
         @locking.ssynchronized(_config_lock)
         def AddNodeGroup(self, group, ec_id, check_uuid=True):
           """Add a node group to the configuration.
           This method calls group.UpgradeConfig() to fill any missing attributes
           according to their default values.
           @type group: L{objects.NodeGroup}
           @param group: the NodeGroup object to add
           @type ec_id: string
           @param ec_id: unique id for the job to use when creating a missing UUID
           @type check_uuid: bool
           @param check_uuid: add an UUID to the group if it doesn't have one or, if
                              it does, ensure that it does not exist in the
                              configuration already
           """
           self._UnlockedAddNodeGroup(group, ec_id, check_uuid)
           self._WriteConfig()
         def _UnlockedAddNodeGroup(self, group, ec_id, check_uuid):
           """Add a node group to the configuration.
           """
           logging.info("Adding node group %s to configuration", group.name)
           # Some code might need to add a node group with a pre-populated UUID
           # generated with ConfigWriter.GenerateUniqueID(). We allow them to bypass
           # the "does this UUID" exist already check.
           if check_uuid:
             self._EnsureUUID(group, ec_id)
           try:
             existing_uuid = self._UnlockedLookupNodeGroup(group.name)
           except errors.OpPrereqError:
             pass
           else:
             raise errors.OpPrereqError("Desired group name '%s' already exists as a"
                                        " node group (UUID: %s)" %
                                        (group.name, existing_uuid),
                                        errors.ECODE_EXISTS)
           group.serial_no = 1
           group.ctime = group.mtime = time.time()
           group.UpgradeConfig()
           self._config_data.nodegroups[group.uuid] = group
           self._config_data.cluster.serial_no += 1
         @locking.ssynchronized(_config_lock)
         def RemoveNodeGroup(self, group_uuid):
           """Remove a node group from the configuration.
           @type group_uuid: string
           @param group_uuid: the UUID of the node group to remove
           """
           logging.info("Removing node group %s from configuration", group_uuid)
           if group_uuid not in self._config_data.nodegroups:
             raise errors.ConfigurationError("Unknown node group '%s'" % group_uuid)
           assert len(self._config_data.nodegroups) != 1, \
                   "Group '%s' is the only group, cannot be removed" % group_uuid
           del self._config_data.nodegroups[group_uuid]
           self._config_data.cluster.serial_no += 1
           self._WriteConfig()
         def _UnlockedLookupNodeGroup(self, target):
           """Lookup a node group's UUID.
           @type target: string or None
           @param target: group name or UUID or None to look for the default
           @rtype: string
           @return: nodegroup UUID
           @raises errors.OpPrereqError: when the target group cannot be found
           """
           if target is None:
             if len(self._config_data.nodegroups) != 1:
               raise errors.OpPrereqError("More than one node group exists. Target"
                                          " group must be specified explicitely.")
             else:
               return self._config_data.nodegroups.keys()[0]
           if target in self._config_data.nodegroups:
             return target
           for nodegroup in self._config_data.nodegroups.values():
             if nodegroup.name == target:
               return nodegroup.uuid
           raise errors.OpPrereqError("Node group '%s' not found" % target,
                                      errors.ECODE_NOENT)
         @locking.ssynchronized(_config_lock, shared=1)
         def LookupNodeGroup(self, target):
           """Lookup a node group's UUID.
           This function is just a wrapper over L{_UnlockedLookupNodeGroup}.
           @type target: string or None
           @param target: group name or UUID or None to look for the default
           @rtype: string
           @return: nodegroup UUID
           """
           return self._UnlockedLookupNodeGroup(target)
         def _UnlockedGetNodeGroup(self, uuid):
           """Lookup a node group.
           @type uuid: string
           @param uuid: group UUID
           @rtype: L{objects.NodeGroup} or None
           @return: nodegroup object, or None if not found
           """
           if uuid not in self._config_data.nodegroups:
             return None
           return self._config_data.nodegroups[uuid]
         @locking.ssynchronized(_config_lock, shared=1)
         def GetNodeGroup(self, uuid):
           """Lookup a node group.
           @type uuid: string
           @param uuid: group UUID
           @rtype: L{objects.NodeGroup} or None
           @return: nodegroup object, or None if not found
           """
           return self._UnlockedGetNodeGroup(uuid)
         @locking.ssynchronized(_config_lock, shared=1)
         def GetAllNodeGroupsInfo(self):
           """Get the configuration of all node groups.
           """
           return dict(self._config_data.nodegroups)
         @locking.ssynchronized(_config_lock, shared=1)
         def GetNodeGroupList(self):
           """Get a list of node groups.
           """
           return self._config_data.nodegroups.keys()
         @locking.ssynchronized(_config_lock, shared=1)
         def GetNodeGroupMembersByNodes(self, nodes):
           """Get nodes which are member in the same nodegroups as the given nodes.
           """
           ngfn = lambda node_name: self._UnlockedGetNodeInfo(node_name).group
           return frozenset(member_name
                            for node_name in nodes
                            for member_name in
                              self._UnlockedGetNodeGroup(ngfn(node_name)).members)
         @locking.ssynchronized(_config_lock)
         def AddInstance(self, instance, ec_id):
           """Add an instance to the config.
           This should be used after creating a new instance.
           @type instance: L{objects.Instance}
           @param instance: the instance object
           """
           if not isinstance(instance, objects.Instance):
             raise errors.ProgrammerError("Invalid type passed to AddInstance")
           if instance.disk_template != constants.DT_DISKLESS:
             all_lvs = instance.MapLVsByNode()
             logging.info("Instance '%s' DISK_LAYOUT: %s", instance.name, all_lvs)
           all_macs = self._AllMACs()
           for nic in instance.nics:
             if nic.mac in all_macs:
               raise errors.ConfigurationError("Cannot add instance %s:"
                                               " MAC address '%s' already in use." %
                                               (instance.name, nic.mac))
           self._EnsureUUID(instance, ec_id)
           instance.serial_no = 1
           instance.ctime = instance.mtime = time.time()
           self._config_data.instances[instance.name] = instance
           self._config_data.cluster.serial_no += 1
           self._UnlockedReleaseDRBDMinors(instance.name)
           self._WriteConfig()
         def _EnsureUUID(self, item, ec_id):
           """Ensures a given object has a valid UUID.
           @param item: the instance or node to be checked
           @param ec_id: the execution context id for the uuid reservation
           """
           if not item.uuid:
             item.uuid = self._GenerateUniqueID(ec_id)
           elif item.uuid in self._AllIDs(include_temporary=True):
             raise errors.ConfigurationError("Cannot add '%s': UUID %s already"
                                             " in use" % (item.name, item.uuid))
         def _SetInstanceStatus(self, instance_name, status):
           """Set the instance's status to a given value.
           """
           assert status in constants.ADMINST_ALL, \
                  "Invalid status '%s' passed to SetInstanceStatus" % (status,)
           if instance_name not in self._config_data.instances:
             raise errors.ConfigurationError("Unknown instance '%s'" %
                                             instance_name)
           instance = self._config_data.instances[instance_name]
           if instance.admin_state != status:
             instance.admin_state = status
             instance.serial_no += 1
             instance.mtime = time.time()
             self._WriteConfig()
         @locking.ssynchronized(_config_lock)
         def MarkInstanceUp(self, instance_name):
           """Mark the instance status to up in the config.
           """
           self._SetInstanceStatus(instance_name, constants.ADMINST_UP)
         @locking.ssynchronized(_config_lock)
         def MarkInstanceOffline(self, instance_name):
           """Mark the instance status to down in the config.
           """
           self._SetInstanceStatus(instance_name, constants.ADMINST_OFFLINE)
         @locking.ssynchronized(_config_lock)
         def RemoveInstance(self, instance_name):
           """Remove the instance from the configuration.
           """
           if instance_name not in self._config_data.instances:
             raise errors.ConfigurationError("Unknown instance '%s'" % instance_name)
           # If a network port has been allocated to the instance,
           # return it to the pool of free ports.
           inst = self._config_data.instances[instance_name]
           network_port = getattr(inst, "network_port", None)
           if network_port is not None:
             self._config_data.cluster.tcpudp_port_pool.add(network_port)
           del self._config_data.instances[instance_name]
           self._config_data.cluster.serial_no += 1
           self._WriteConfig()
         @locking.ssynchronized(_config_lock)
         def RenameInstance(self, old_name, new_name):
           """Rename an instance.
           This needs to be done in ConfigWriter and not by RemoveInstance
           combined with AddInstance as only we can guarantee an atomic
           rename.
           """
           if old_name not in self._config_data.instances:
             raise errors.ConfigurationError("Unknown instance '%s'" % old_name)
           # Operate on a copy to not loose instance object in case of a failure
           inst = self._config_data.instances[old_name].Copy()
           inst.name = new_name
           for (idx, disk) in enumerate(inst.disks):
             if disk.dev_type == constants.LD_FILE:
               # rename the file paths in logical and physical id
               file_storage_dir = os.path.dirname(os.path.dirname(disk.logical_id[1]))
               disk.logical_id = (disk.logical_id[0],
                                  utils.PathJoin(file_storage_dir, inst.name,
                                                 "disk%s" % idx))
               disk.physical_id = disk.logical_id
           # Actually replace instance object
           del self._config_data.instances[old_name]
           self._config_data.instances[inst.name] = inst
           # Force update of ssconf files
           self._config_data.cluster.serial_no += 1
           self._WriteConfig()
         @locking.ssynchronized(_config_lock)
         def MarkInstanceDown(self, instance_name):
           """Mark the status of an instance to down in the configuration.
           """
           self._SetInstanceStatus(instance_name, constants.ADMINST_DOWN)
         def _UnlockedGetInstanceList(self):
           """Get the list of instances.
           This function is for internal use, when the config lock is already held.
           """
           return self._config_data.instances.keys()
         @locking.ssynchronized(_config_lock, shared=1)
         def GetInstanceList(self):
           """Get the list of instances.
           @return: array of instances, ex. ['instance2.example.com',
               'instance1.example.com']
           """
           return self._UnlockedGetInstanceList()
         def ExpandInstanceName(self, short_name):
           """Attempt to expand an incomplete instance name.
           """
           # Locking is done in L{ConfigWriter.GetInstanceList}
           return _MatchNameComponentIgnoreCase(short_name, self.GetInstanceList())
         def _UnlockedGetInstanceInfo(self, instance_name):
           """Returns information about an instance.
           This function is for internal use, when the config lock is already held.
           """
           if instance_name not in self._config_data.instances:
             return None
           return self._config_data.instances[instance_name]
         @locking.ssynchronized(_config_lock, shared=1)
         def GetInstanceInfo(self, instance_name):
           """Returns information about an instance.
           It takes the information from the configuration file. Other information of
           an instance are taken from the live systems.
           @param instance_name: name of the instance, e.g.
               I{instance1.example.com}
           @rtype: L{objects.Instance}
           @return: the instance object
           """
           return self._UnlockedGetInstanceInfo(instance_name)
         @locking.ssynchronized(_config_lock, shared=1)
         def GetInstanceNodeGroups(self, instance_name, primary_only=False):
           """Returns set of node group UUIDs for instance's nodes.
           @rtype: frozenset
           """
           instance = self._UnlockedGetInstanceInfo(instance_name)
           if not instance:
             raise errors.ConfigurationError("Unknown instance '%s'" % instance_name)
           if primary_only:
             nodes = [instance.primary_node]
           else:
             nodes = instance.all_nodes
           return frozenset(self._UnlockedGetNodeInfo(node_name).group
                            for node_name in nodes)
         @locking.ssynchronized(_config_lock, shared=1)
         def GetMultiInstanceInfo(self, instances):
           """Get the configuration of multiple instances.
           @param instances: list of instance names
           @rtype: list
           @return: list of tuples (instance, instance_info), where
               instance_info is what would GetInstanceInfo return for the
               node, while keeping the original order
           """
           return [(name, self._UnlockedGetInstanceInfo(name)) for name in instances]
         @locking.ssynchronized(_config_lock, shared=1)
         def GetAllInstancesInfo(self):
           """Get the configuration of all instances.
           @rtype: dict
           @return: dict of (instance, instance_info), where instance_info is what
                     would GetInstanceInfo return for the node
           """
           my_dict = dict([(instance, self._UnlockedGetInstanceInfo(instance))
                           for instance in self._UnlockedGetInstanceList()])
           return my_dict
         @locking.ssynchronized(_config_lock, shared=1)
         def GetInstancesInfoByFilter(self, filter_fn):
           """Get instance configuration with a filter.
           @type filter_fn: callable
           @param filter_fn: Filter function receiving instance object as parameter,
             returning boolean. Important: this function is called while the
             configuration locks is held. It must not do any complex work or call
             functions potentially leading to a deadlock. Ideally it doesn't call any
             other functions and just compares instance attributes.
           """
           return dict((name, inst)
                       for (name, inst) in self._config_data.instances.items()
                       if filter_fn(inst))
         @locking.ssynchronized(_config_lock)
         def AddNode(self, node, ec_id):
           """Add a node to the configuration.
           @type node: L{objects.Node}
           @param node: a Node instance
           """
           logging.info("Adding node %s to configuration", node.name)
           self._EnsureUUID(node, ec_id)
           node.serial_no = 1
           node.ctime = node.mtime = time.time()
           self._UnlockedAddNodeToGroup(node.name, node.group)
           self._config_data.nodes[node.name] = node
           self._config_data.cluster.serial_no += 1
           self._WriteConfig()
         @locking.ssynchronized(_config_lock)
         def RemoveNode(self, node_name):
           """Remove a node from the configuration.
           """
           logging.info("Removing node %s from configuration", node_name)
           if node_name not in self._config_data.nodes:
             raise errors.ConfigurationError("Unknown node '%s'" % node_name)
           self._UnlockedRemoveNodeFromGroup(self._config_data.nodes[node_name])
           del self._config_data.nodes[node_name]
           self._config_data.cluster.serial_no += 1
           self._WriteConfig()
         def ExpandNodeName(self, short_name):
           """Attempt to expand an incomplete node name.
           """
           # Locking is done in L{ConfigWriter.GetNodeList}
           return _MatchNameComponentIgnoreCase(short_name, self.GetNodeList())
         def _UnlockedGetNodeInfo(self, node_name):
           """Get the configuration of a node, as stored in the config.
           This function is for internal use, when the config lock is already
           held.
           @param node_name: the node name, e.g. I{node1.example.com}
           @rtype: L{objects.Node}
           @return: the node object
           """
           if node_name not in self._config_data.nodes:
             return None
           return self._config_data.nodes[node_name]
         @locking.ssynchronized(_config_lock, shared=1)
         def GetNodeInfo(self, node_name):
           """Get the configuration of a node, as stored in the config.
           This is just a locked wrapper over L{_UnlockedGetNodeInfo}.
           @param node_name: the node name, e.g. I{node1.example.com}
           @rtype: L{objects.Node}
           @return: the node object
           """
           return self._UnlockedGetNodeInfo(node_name)
         @locking.ssynchronized(_config_lock, shared=1)
         def GetNodeInstances(self, node_name):
           """Get the instances of a node, as stored in the config.
           @param node_name: the node name, e.g. I{node1.example.com}
           @rtype: (list, list)
           @return: a tuple with two lists: the primary and the secondary instances
           """
           pri = []
           sec = []
           for inst in self._config_data.instances.values():
             if inst.primary_node == node_name:
               pri.append(inst.name)
             if node_name in inst.secondary_nodes:
               sec.append(inst.name)
           return (pri, sec)
         @locking.ssynchronized(_config_lock, shared=1)
         def GetNodeGroupInstances(self, uuid, primary_only=False):
           """Get the instances of a node group.
           @param uuid: Node group UUID
           @param primary_only: Whether to only consider primary nodes
           @rtype: frozenset
           @return: List of instance names in node group
           """
           if primary_only:
             nodes_fn = lambda inst: [inst.primary_node]
           else:
             nodes_fn = lambda inst: inst.all_nodes
           return frozenset(inst.name
                            for inst in self._config_data.instances.values()
                            for node_name in nodes_fn(inst)
                            if self._UnlockedGetNodeInfo(node_name).group == uuid)
         def _UnlockedGetNodeList(self):
           """Return the list of nodes which are in the configuration.
           This function is for internal use, when the config lock is already
           held.
           @rtype: list
           """
           return self._config_data.nodes.keys()
         @locking.ssynchronized(_config_lock, shared=1)
         def GetNodeList(self):
           """Return the list of nodes which are in the configuration.
           """
           return self._UnlockedGetNodeList()
         def _UnlockedGetOnlineNodeList(self):
           """Return the list of nodes which are online.
           """
           all_nodes = [self._UnlockedGetNodeInfo(node)
                        for node in self._UnlockedGetNodeList()]
           return [node.name for node in all_nodes if not node.offline]
         @locking.ssynchronized(_config_lock, shared=1)
         def GetOnlineNodeList(self):
           """Return the list of nodes which are online.
           """
           return self._UnlockedGetOnlineNodeList()
         @locking.ssynchronized(_config_lock, shared=1)
         def GetVmCapableNodeList(self):
           """Return the list of nodes which are not vm capable.
           """
           all_nodes = [self._UnlockedGetNodeInfo(node)
                        for node in self._UnlockedGetNodeList()]
           return [node.name for node in all_nodes if node.vm_capable]
         @locking.ssynchronized(_config_lock, shared=1)
         def GetNonVmCapableNodeList(self):
           """Return the list of nodes which are not vm capable.
           """
           all_nodes = [self._UnlockedGetNodeInfo(node)
                        for node in self._UnlockedGetNodeList()]
           return [node.name for node in all_nodes if not node.vm_capable]
         @locking.ssynchronized(_config_lock, shared=1)
         def GetMultiNodeInfo(self, nodes):
           """Get the configuration of multiple nodes.
           @param nodes: list of node names
           @rtype: list
           @return: list of tuples of (node, node_info), where node_info is
               what would GetNodeInfo return for the node, in the original
               order
           """
           return [(name, self._UnlockedGetNodeInfo(name)) for name in nodes]
         @locking.ssynchronized(_config_lock, shared=1)
         def GetAllNodesInfo(self):
           """Get the configuration of all nodes.
           @rtype: dict
           @return: dict of (node, node_info), where node_info is what
                     would GetNodeInfo return for the node
           """
           return self._UnlockedGetAllNodesInfo()
         def _UnlockedGetAllNodesInfo(self):
           """Gets configuration of all nodes.
           @note: See L{GetAllNodesInfo}
           """
           return dict([(node, self._UnlockedGetNodeInfo(node))
                        for node in self._UnlockedGetNodeList()])
         @locking.ssynchronized(_config_lock, shared=1)
         def GetNodeGroupsFromNodes(self, nodes):
           """Returns groups for a list of nodes.
           @type nodes: list of string
           @param nodes: List of node names
           @rtype: frozenset
           """
           return frozenset(self._UnlockedGetNodeInfo(name).group for name in nodes)
         def _UnlockedGetMasterCandidateStats(self, exceptions=None):
           """Get the number of current and maximum desired and possible candidates.
           @type exceptions: list
           @param exceptions: if passed, list of nodes that should be ignored
           @rtype: tuple
           @return: tuple of (current, desired and possible, possible)
           """
           mc_now = mc_should = mc_max = 0
           for node in self._config_data.nodes.values():
             if exceptions and node.name in exceptions:
               continue
             if not (node.offline or node.drained) and node.master_capable:
               mc_max += 1
             if node.master_candidate:
               mc_now += 1
           mc_should = min(mc_max, self._config_data.cluster.candidate_pool_size)
           return (mc_now, mc_should, mc_max)
         @locking.ssynchronized(_config_lock, shared=1)
         def GetMasterCandidateStats(self, exceptions=None):
           """Get the number of current and maximum possible candidates.
           This is just a wrapper over L{_UnlockedGetMasterCandidateStats}.
           @type exceptions: list
           @param exceptions: if passed, list of nodes that should be ignored
           @rtype: tuple
           @return: tuple of (current, max)
           """
           return self._UnlockedGetMasterCandidateStats(exceptions)
         @locking.ssynchronized(_config_lock)
         def MaintainCandidatePool(self, exceptions):
           """Try to grow the candidate pool to the desired size.
           @type exceptions: list
           @param exceptions: if passed, list of nodes that should be ignored
           @rtype: list
           @return: list with the adjusted nodes (L{objects.Node} instances)
           """
           mc_now, mc_max, _ = self._UnlockedGetMasterCandidateStats(exceptions)
           mod_list = []
           if mc_now < mc_max:
             node_list = self._config_data.nodes.keys()
             random.shuffle(node_list)
             for name in node_list:
               if mc_now >= mc_max:
                 break
               node = self._config_data.nodes[name]
               if (node.master_candidate or node.offline or node.drained or
                   node.name in exceptions or not node.master_capable):
                 continue
               mod_list.append(node)
               node.master_candidate = True
               node.serial_no += 1
               mc_now += 1
             if mc_now != mc_max:
               # this should not happen
               logging.warning("Warning: MaintainCandidatePool didn't manage to"
                               " fill the candidate pool (%d/%d)", mc_now, mc_max)
             if mod_list:
               self._config_data.cluster.serial_no += 1
               self._WriteConfig()
           return mod_list
         def _UnlockedAddNodeToGroup(self, node_name, nodegroup_uuid):
           """Add a given node to the specified group.
           """
           if nodegroup_uuid not in self._config_data.nodegroups:
             # This can happen if a node group gets deleted between its lookup and
             # when we're adding the first node to it, since we don't keep a lock in
             # the meantime. It's ok though, as we'll fail cleanly if the node group
             # is not found anymore.
             raise errors.OpExecError("Unknown node group: %s" % nodegroup_uuid)
           if node_name not in self._config_data.nodegroups[nodegroup_uuid].members:
             self._config_data.nodegroups[nodegroup_uuid].members.append(node_name)
         def _UnlockedRemoveNodeFromGroup(self, node):
           """Remove a given node from its group.
           """
           nodegroup = node.group
           if nodegroup not in self._config_data.nodegroups:
             logging.warning("Warning: node '%s' has unknown node group '%s'"
                             " (while being removed from it)", node.name, nodegroup)
           nodegroup_obj = self._config_data.nodegroups[nodegroup]
           if node.name not in nodegroup_obj.members:
             logging.warning("Warning: node '%s' not a member of its node group '%s'"
                             " (while being removed from it)", node.name, nodegroup)
           else:
             nodegroup_obj.members.remove(node.name)
         @locking.ssynchronized(_config_lock)
         def AssignGroupNodes(self, mods):
           """Changes the group of a number of nodes.
           @type mods: list of tuples; (node name, new group UUID)
           @param mods: Node membership modifications
           """
           groups = self._config_data.nodegroups
           nodes = self._config_data.nodes
           resmod = []
           # Try to resolve names/UUIDs first
           for (node_name, new_group_uuid) in mods:
             try:
               node = nodes[node_name]
             except KeyError:
               raise errors.ConfigurationError("Unable to find node '%s'" % node_name)
             if node.group == new_group_uuid:
               # Node is being assigned to its current group
               logging.debug("Node '%s' was assigned to its current group (%s)",
                             node_name, node.group)
               continue
             # Try to find current group of node
             try:
               old_group = groups[node.group]
             except KeyError:
               raise errors.ConfigurationError("Unable to find old group '%s'" %
                                               node.group)
             # Try to find new group for node
             try:
               new_group = groups[new_group_uuid]
             except KeyError:
               raise errors.ConfigurationError("Unable to find new group '%s'" %
                                               new_group_uuid)
             assert node.name in old_group.members, \
               ("Inconsistent configuration: node '%s' not listed in members for its"
                " old group '%s'" % (node.name, old_group.uuid))
             assert node.name not in new_group.members, \
               ("Inconsistent configuration: node '%s' already listed in members for"
                " its new group '%s'" % (node.name, new_group.uuid))
             resmod.append((node, old_group, new_group))
           # Apply changes
           for (node, old_group, new_group) in resmod:
             assert node.uuid != new_group.uuid and old_group.uuid != new_group.uuid, \
               "Assigning to current group is not possible"
             node.group = new_group.uuid
             # Update members of involved groups
             if node.name in old_group.members:
               old_group.members.remove(node.name)
             if node.name not in new_group.members:
               new_group.members.append(node.name)
           # Update timestamps and serials (only once per node/group object)
           now = time.time()
           for obj in frozenset(itertools.chain(*resmod)): # pylint: disable=W0142
             obj.serial_no += 1
             obj.mtime = now
           # Force ssconf update
           self._config_data.cluster.serial_no += 1
           self._WriteConfig()
         def _BumpSerialNo(self):
           """Bump up the serial number of the config.
           """
           self._config_data.serial_no += 1
           self._config_data.mtime = time.time()
         def _AllUUIDObjects(self):
           """Returns all objects with uuid attributes.
           """
           return (self._config_data.instances.values() +
                   self._config_data.nodes.values() +
                   self._config_data.nodegroups.values() +
                   [self._config_data.cluster])
         def _OpenConfig(self, accept_foreign):
           """Read the config data from disk.
           """
           raw_data = utils.ReadFile(self._cfg_file)
           try:
             data = objects.ConfigData.FromDict(serializer.Load(raw_data))
           except Exception, err:
             raise errors.ConfigurationError(err)
           # Make sure the configuration has the right version
           _ValidateConfig(data)
           if (not hasattr(data, 'cluster') or
               not hasattr(data.cluster, 'rsahostkeypub')):
             raise errors.ConfigurationError("Incomplete configuration"
                                             " (missing cluster.rsahostkeypub)")
           if data.cluster.master_node != self._my_hostname and not accept_foreign:
             msg = ("The configuration denotes node %s as master, while my"
                    " hostname is %s; opening a foreign configuration is only"
                    " possible in accept_foreign mode" %
                    (data.cluster.master_node, self._my_hostname))
             raise errors.ConfigurationError(msg)
           # Upgrade configuration if needed
           data.UpgradeConfig()
           self._config_data = data
           # reset the last serial as -1 so that the next write will cause
           # ssconf update
           self._last_cluster_serial = -1
           # And finally run our (custom) config upgrade sequence
           self._UpgradeConfig()
           self._cfg_id = utils.GetFileID(path=self._cfg_file)
         def _UpgradeConfig(self):
           """Run upgrade steps that cannot be done purely in the objects.
           This is because some data elements need uniqueness across the
           whole configuration, etc.
           @warning: this function will call L{_WriteConfig()}, but also
               L{DropECReservations} so it needs to be called only from a
               "safe" place (the constructor). If one wanted to call it with
               the lock held, a DropECReservationUnlocked would need to be
               created first, to avoid causing deadlock.
           """
           modified = False
           for item in self._AllUUIDObjects():
             if item.uuid is None:
               item.uuid = self._GenerateUniqueID(_UPGRADE_CONFIG_JID)
               modified = True
           if not self._config_data.nodegroups:
             default_nodegroup_name = constants.INITIAL_NODE_GROUP_NAME
             default_nodegroup = objects.NodeGroup(name=default_nodegroup_name,
                                                   members=[])
             self._UnlockedAddNodeGroup(default_nodegroup, _UPGRADE_CONFIG_JID, True)
             modified = True
           for node in self._config_data.nodes.values():
             if not node.group:
               node.group = self.LookupNodeGroup(None)
               modified = True
             # This is technically *not* an upgrade, but needs to be done both when
             # nodegroups are being added, and upon normally loading the config,
             # because the members list of a node group is discarded upon
             # serializing/deserializing the object.
             self._UnlockedAddNodeToGroup(node.name, node.group)
           if modified:
             self._WriteConfig()
             # This is ok even if it acquires the internal lock, as _UpgradeConfig is
             # only called at config init time, without the lock held
             self.DropECReservations(_UPGRADE_CONFIG_JID)
         def _DistributeConfig(self, feedback_fn):
           """Distribute the configuration to the other nodes.
           Currently, this only copies the configuration file. In the future,
           it could be used to encapsulate the 2/3-phase update mechanism.
           """
           if self._offline:
             return True
           bad = False
           node_list = []
           addr_list = []
           myhostname = self._my_hostname
           # we can skip checking whether _UnlockedGetNodeInfo returns None
           # since the node list comes from _UnlocketGetNodeList, and we are
           # called with the lock held, so no modifications should take place
           # in between
           for node_name in self._UnlockedGetNodeList():
             if node_name == myhostname:
               continue
             node_info = self._UnlockedGetNodeInfo(node_name)
             if not node_info.master_candidate:
               continue
             node_list.append(node_info.name)
             addr_list.append(node_info.primary_ip)
           # TODO: Use dedicated resolver talking to config writer for name resolution
           result = \
             self._GetRpc(addr_list).call_upload_file(node_list, self._cfg_file)
           for to_node, to_result in result.items():
             msg = to_result.fail_msg
             if msg:
               msg = ("Copy of file %s to node %s failed: %s" %
                      (self._cfg_file, to_node, msg))
               logging.error(msg)
               if feedback_fn:
                 feedback_fn(msg)
               bad = True
           return not bad
         def _WriteConfig(self, destination=None, feedback_fn=None):
           """Write the configuration data to persistent storage.
           """
           assert feedback_fn is None or callable(feedback_fn)
           # Warn on config errors, but don't abort the save - the
           # configuration has already been modified, and we can't revert;
           # the best we can do is to warn the user and save as is, leaving
           # recovery to the user
           config_errors = self._UnlockedVerifyConfig()
           if config_errors:
             errmsg = ("Configuration data is not consistent: %s" %
                       (utils.CommaJoin(config_errors)))
             logging.critical(errmsg)
             if feedback_fn:
               feedback_fn(errmsg)
           if destination is None:
             destination = self._cfg_file
           self._BumpSerialNo()
           txt = serializer.Dump(self._config_data.ToDict())
           getents = self._getents()
           try:
             fd = utils.SafeWriteFile(destination, self._cfg_id, data=txt,
                                      close=False, gid=getents.confd_gid, mode=0640)
           except errors.LockError:
             raise errors.ConfigurationError("The configuration file has been"
                                             " modified since the last write, cannot"
                                             " update")
           try:
             self._cfg_id = utils.GetFileID(fd=fd)
           finally:
             os.close(fd)
           self.write_count += 1
           # and redistribute the config file to master candidates
           self._DistributeConfig(feedback_fn)
           # Write ssconf files on all nodes (including locally)
           if self._last_cluster_serial < self._config_data.cluster.serial_no:
             if not self._offline:
               result = self._GetRpc(None).call_write_ssconf_files(
                 self._UnlockedGetOnlineNodeList(),
                 self._UnlockedGetSsconfValues())
               for nname, nresu in result.items():
                 msg = nresu.fail_msg
                 if msg:
                   errmsg = ("Error while uploading ssconf files to"
                             " node %s: %s" % (nname, msg))
                   logging.warning(errmsg)
                   if feedback_fn:
                     feedback_fn(errmsg)
             self._last_cluster_serial = self._config_data.cluster.serial_no
         def _UnlockedGetSsconfValues(self):
           """Return the values needed by ssconf.
           @rtype: dict
           @return: a dictionary with keys the ssconf names and values their
               associated value
           """
           fn = "\n".join
           instance_names = utils.NiceSort(self._UnlockedGetInstanceList())
           node_names = utils.NiceSort(self._UnlockedGetNodeList())
           node_info = [self._UnlockedGetNodeInfo(name) for name in node_names]
           node_pri_ips = ["%s %s" % (ninfo.name, ninfo.primary_ip)
                           for ninfo in node_info]
           node_snd_ips = ["%s %s" % (ninfo.name, ninfo.secondary_ip)
                           for ninfo in node_info]
           instance_data = fn(instance_names)
           off_data = fn(node.name for node in node_info if node.offline)
           on_data = fn(node.name for node in node_info if not node.offline)
           mc_data = fn(node.name for node in node_info if node.master_candidate)
           mc_ips_data = fn(node.primary_ip for node in node_info
                            if node.master_candidate)
           node_data = fn(node_names)
           node_pri_ips_data = fn(node_pri_ips)
           node_snd_ips_data = fn(node_snd_ips)
           cluster = self._config_data.cluster
           cluster_tags = fn(cluster.GetTags())
           hypervisor_list = fn(cluster.enabled_hypervisors)
           uid_pool = uidpool.FormatUidPool(cluster.uid_pool, separator="\n")
           nodegroups = ["%s %s" % (nodegroup.uuid, nodegroup.name) for nodegroup in
                         self._config_data.nodegroups.values()]
           nodegroups_data = fn(utils.NiceSort(nodegroups))
           ssconf_values = {
             constants.SS_CLUSTER_NAME: cluster.cluster_name,
             constants.SS_CLUSTER_TAGS: cluster_tags,
             constants.SS_FILE_STORAGE_DIR: cluster.file_storage_dir,
             constants.SS_SHARED_FILE_STORAGE_DIR: cluster.shared_file_storage_dir,
             constants.SS_MASTER_CANDIDATES: mc_data,
             constants.SS_MASTER_CANDIDATES_IPS: mc_ips_data,
             constants.SS_MASTER_IP: cluster.master_ip,
             constants.SS_MASTER_NETDEV: cluster.master_netdev,
             constants.SS_MASTER_NETMASK: str(cluster.master_netmask),
             constants.SS_MASTER_NODE: cluster.master_node,
             constants.SS_NODE_LIST: node_data,
             constants.SS_NODE_PRIMARY_IPS: node_pri_ips_data,
             constants.SS_NODE_SECONDARY_IPS: node_snd_ips_data,
             constants.SS_OFFLINE_NODES: off_data,
             constants.SS_ONLINE_NODES: on_data,
             constants.SS_PRIMARY_IP_FAMILY: str(cluster.primary_ip_family),
             constants.SS_INSTANCE_LIST: instance_data,
             constants.SS_RELEASE_VERSION: constants.RELEASE_VERSION,
             constants.SS_HYPERVISOR_LIST: hypervisor_list,
             constants.SS_MAINTAIN_NODE_HEALTH: str(cluster.maintain_node_health),
             constants.SS_UID_POOL: uid_pool,
             constants.SS_NODEGROUPS: nodegroups_data,
+            }
           bad_values = [(k, v) for k, v in ssconf_values.items()
                         if not isinstance(v, (str, basestring))]
           if bad_values:
             err = utils.CommaJoin("%s=%s" % (k, v) for k, v in bad_values)
             raise errors.ConfigurationError("Some ssconf key(s) have non-string"
                                             " values: %s" % err)
           return ssconf_values
         @locking.ssynchronized(_config_lock, shared=1)
         def GetSsconfValues(self):
           """Wrapper using lock around _UnlockedGetSsconf().
           """
           return self._UnlockedGetSsconfValues()
         @locking.ssynchronized(_config_lock, shared=1)
         def GetVGName(self):
           """Return the volume group name.
           """
           return self._config_data.cluster.volume_group_name
         @locking.ssynchronized(_config_lock)
         def SetVGName(self, vg_name):
           """Set the volume group name.
           """
           self._config_data.cluster.volume_group_name = vg_name
           self._config_data.cluster.serial_no += 1
           self._WriteConfig()
         @locking.ssynchronized(_config_lock, shared=1)
         def GetDRBDHelper(self):
           """Return DRBD usermode helper.
           """
           return self._config_data.cluster.drbd_usermode_helper
         @locking.ssynchronized(_config_lock)
         def SetDRBDHelper(self, drbd_helper):
           """Set DRBD usermode helper.
           """
           self._config_data.cluster.drbd_usermode_helper = drbd_helper
           self._config_data.cluster.serial_no += 1
           self._WriteConfig()
         @locking.ssynchronized(_config_lock, shared=1)
         def GetMACPrefix(self):
           """Return the mac prefix.
           """
           return self._config_data.cluster.mac_prefix
         @locking.ssynchronized(_config_lock, shared=1)
         def GetClusterInfo(self):
           """Returns information about the cluster
           @rtype: L{objects.Cluster}
           @return: the cluster object
           """
           return self._config_data.cluster
         @locking.ssynchronized(_config_lock, shared=1)
         def HasAnyDiskOfType(self, dev_type):
           """Check if in there is at disk of the given type in the configuration.
           """
           return self._config_data.HasAnyDiskOfType(dev_type)
         @locking.ssynchronized(_config_lock)
         def Update(self, target, feedback_fn):
           """Notify function to be called after updates.
           This function must be called when an object (as returned by
           GetInstanceInfo, GetNodeInfo, GetCluster) has been updated and the
           caller wants the modifications saved to the backing store. Note
           that all modified objects will be saved, but the target argument
           is the one the caller wants to ensure that it's saved.
           @param target: an instance of either L{objects.Cluster},
               L{objects.Node} or L{objects.Instance} which is existing in
               the cluster
           @param feedback_fn: Callable feedback function
           """
           if self._config_data is None:
             raise errors.ProgrammerError("Configuration file not read,"
                                          " cannot save.")
           update_serial = False
           if isinstance(target, objects.Cluster):
             test = target == self._config_data.cluster
           elif isinstance(target, objects.Node):
             test = target in self._config_data.nodes.values()
             update_serial = True
           elif isinstance(target, objects.Instance):
             test = target in self._config_data.instances.values()
           elif isinstance(target, objects.NodeGroup):
             test = target in self._config_data.nodegroups.values()
           else:
             raise errors.ProgrammerError("Invalid object type (%s) passed to"
                                          " ConfigWriter.Update" % type(target))
           if not test:
             raise errors.ConfigurationError("Configuration updated since object"
                                             " has been read or unknown object")
           target.serial_no += 1
           target.mtime = now = time.time()
           if update_serial:
             # for node updates, we need to increase the cluster serial too
             self._config_data.cluster.serial_no += 1
             self._config_data.cluster.mtime = now
           if isinstance(target, objects.Instance):
             self._UnlockedReleaseDRBDMinors(target.name)
           self._WriteConfig(feedback_fn=feedback_fn)
         @locking.ssynchronized(_config_lock)
         def DropECReservations(self, ec_id):
           """Drop per-execution-context reservations
           """
           for rm in self._all_rms:
             rm.DropECReservations(ec_id)

Synnefo » snf-ganeti » ganeti-local

root / lib / config.py @ 82c54b5b