Synnefo » snf-ganeti

#

#

# Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014 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 copy

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

import ganeti.rpc.node as rpc

from ganeti import objects

from ganeti import serializer

from ganeti import uidpool

from ganeti import netutils

from ganeti import runtime

from ganeti import pathutils

from ganeti import network

_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 GetECReserved(self, ec_id):

    """ Used when you want to retrieve all reservations for a specific

        execution context. E.g when commiting reserved IPs for a specific

        network.

    """

    ec_reserved = set()

    if ec_id in self._ec_reserved:

      ec_reserved.update(self._ec_reserved[ec_id])

    return ec_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(object):

  """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 = pathutils.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._temporary_ips = TemporaryReservationManager()

    self._all_rms = [self._temporary_ids, self._temporary_macs,

                     self._temporary_secrets, self._temporary_lvs,

                     self._temporary_ips]

    # 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(pathutils.CLUSTER_CONF_FILE)

  @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 GetNdGroupParams(self, nodegroup):

    """Get the node groups params populated with cluster defaults.

    @type nodegroup: L{objects.NodeGroup}

    @param nodegroup: The node group we want to know the params for

    @return: A dict with the filled in node group params

    """

    return self._config_data.cluster.FillNDGroup(nodegroup)

  @locking.ssynchronized(_config_lock, shared=1)

  def GetInstanceDiskParams(self, instance):

    """Get the disk params populated with inherit chain.

    @type instance: L{objects.Instance}

    @param instance: The instance we want to know the params for

    @return: A dict with the filled in disk params

    """

    node = self._UnlockedGetNodeInfo(instance.primary_node)

    nodegroup = self._UnlockedGetNodeGroup(node.group)

    return self._UnlockedGetGroupDiskParams(nodegroup)

  # pylint: disable=R0201

  def _UnlockedGetInstanceNodes(self, instance, disks=None):

    """Get all disk-releated nodes for an instance.

    This function is for internal use, when the config lock is already held.

    """

    all_nodes = [instance.primary_node]

    inst_disks = instance.disks

    if disks is not None:

      inst_disks.extend(disks)

    for disk in inst_disks:

      all_nodes.extend(disk.all_nodes)

    return tuple(set(all_nodes))

  @locking.ssynchronized(_config_lock, shared=1)

  def GetInstanceNodes(self, instance, disks=None):

    """Get all disk-releated nodes for an instance.

    For non-DRBD, this will be empty, for DRBD it will contain both

    the primary and the secondaries.

    If additional disks are given, include their nodes to the result.

    This is done because these disks may not be attached to the instance yet.

    @type instance: L{objects.Instance}

    @param instance: The instance we want to get nodes for

    @type disks: list of L{objects.Disk}

    @param disks: If given, include these disks to the result

    @return: A list of names for all the nodes of the instance

    """

    return self._UnlockedGetInstanceNodes(instance, disks=disks)

  def _UnlockedGetInstanceSecondaryNodes(self, instance):

    """Get the list of secondary nodes.

    This function is for internal use, when the config lock is already held.

    """

    all_nodes = set(self._UnlockedGetInstanceNodes(instance))

    all_nodes.discard(instance.primary_node)

    return tuple(all_nodes)

  @locking.ssynchronized(_config_lock, shared=1)

  def GetInstanceSecondaryNodes(self, instance):

    """Get the list of secondary nodes.

    This is a simple wrapper over _UnlockedGetInstanceNodes.

    """

    return self._UnlockedGetInstanceSecondaryNodes(instance)

  # pylint: disable=R0201

  def _UnlockedGetInstanceLVsByNode(self, instance, lvmap=None):

    """Provide a mapping of node to LVs a given instance owns.

    This is a simple wrapper over _UnlockedGetInstanceNodes.

    """

    def _MapLVsByNode(lvmap, devs, node_uuid):

      """Recursively helper function."""

      if not node_uuid in lvmap:

        lvmap[node_uuid] = []

      for dev in devs:

        if dev.dev_type == constants.DT_PLAIN:

          lvmap[node_uuid].append(dev.logical_id[0] + "/" + dev.logical_id[1])

        elif dev.dev_type in constants.DTS_DRBD:

          if dev.children:

            _MapLVsByNode(lvmap, dev.children, dev.logical_id[0])

            _MapLVsByNode(lvmap, dev.children, dev.logical_id[1])

        elif dev.children:

          _MapLVsByNode(lvmap, devs.children, node_uuid)

    if lvmap is None:

      lvmap = {}

      ret = lvmap

    else:

      ret = None

    node_uuid = instance.primary_node

    devs = instance.disks

    _MapLVsByNode(lvmap, devs, node_uuid)

    return ret

  @locking.ssynchronized(_config_lock, shared=1)

  def GetInstanceLVsByNode(self, instance, lvmap=None):

    """Provide a mapping of node to LVs a given instance owns.

    This function figures out what logical volums should belong on

    which nodes, recursing through a device tree.

    @type instance: L{objects.Instance}

    @param instance: The instance we want to compute the LVsByNode for

    @type lvmap: dict

    @param lvmap: optional dictionary to receive the

        'node' : ['lv', ...] data.

    @return: None if lvmap arg is given, otherwise, a dictionary of

        the form { 'node_uuid' : ['volume1', 'volume2', ...], ... };

        volumeN is of the form "vg_name/lv_name", compatible with

        GetVolumeList()

    """

    return self._UnlockedGetInstanceLVsByNode(instance, lvmap=lvmap)

  @locking.ssynchronized(_config_lock, shared=1)

  def GetGroupDiskParams(self, group):

    """Get the disk params populated with inherit chain.

    @type group: L{objects.NodeGroup}

    @param group: The group we want to know the params for

    @return: A dict with the filled in disk params

    """

    return self._UnlockedGetGroupDiskParams(group)

  def _UnlockedGetGroupDiskParams(self, group):

    """Get the disk params populated with inherit chain down to node-group.

    @type group: L{objects.NodeGroup}

    @param group: The group we want to know the params for

    @return: A dict with the filled in disk params

    """

    return self._config_data.cluster.SimpleFillDP(group.diskparams)

  def _UnlockedGetNetworkMACPrefix(self, net_uuid):

    """Return the network mac prefix if it exists or the cluster level default.

    """

    prefix = None

    if net_uuid:

      nobj = self._UnlockedGetNetwork(net_uuid)

      if nobj.mac_prefix:

        prefix = nobj.mac_prefix

    return prefix

  def _GenerateOneMAC(self, prefix=None):

    """Return a function that randomly generates a MAC suffic

       and appends it to the given prefix. If prefix is not given get

       the cluster level default.

    """

    if not prefix:

      prefix = self._config_data.cluster.mac_prefix

    def GenMac():

      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

    return GenMac

  @locking.ssynchronized(_config_lock, shared=1)

  def GenerateMAC(self, net_uuid, ec_id):

    """Generate a MAC for an instance.

    This should check the current instances for duplicates.

    """

    existing = self._AllMACs()

    prefix = self._UnlockedGetNetworkMACPrefix(net_uuid)

    gen_mac = self._GenerateOneMAC(prefix)

    return self._temporary_ids.Generate(existing, gen_mac, 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)

  def _UnlockedCommitTemporaryIps(self, ec_id):

    """Commit all reserved IP address to their respective pools

    """

    for action, address, net_uuid in self._temporary_ips.GetECReserved(ec_id):

      self._UnlockedCommitIp(action, net_uuid, address)

  def _UnlockedCommitIp(self, action, net_uuid, address):

    """Commit a reserved IP address to an IP pool.

    The IP address is taken from the network's IP pool and marked as reserved.

    """

    nobj = self._UnlockedGetNetwork(net_uuid)

    pool = network.AddressPool(nobj)

    if action == constants.RESERVE_ACTION:

      pool.Reserve(address)

    elif action == constants.RELEASE_ACTION:

      pool.Release(address)

  def _UnlockedReleaseIp(self, net_uuid, address, ec_id):

    """Give a specific IP address back to an IP pool.

    The IP address is returned to the IP pool designated by pool_id and marked

    as reserved.

    """

    self._temporary_ips.Reserve(ec_id,

                                (constants.RELEASE_ACTION, address, net_uuid))

  @locking.ssynchronized(_config_lock, shared=1)

  def ReleaseIp(self, net_uuid, address, ec_id):

    """Give a specified IP address back to an IP pool.

    This is just a wrapper around _UnlockedReleaseIp.

    """

    if net_uuid:

      self._UnlockedReleaseIp(net_uuid, address, ec_id)

  @locking.ssynchronized(_config_lock, shared=1)

  def GenerateIp(self, net_uuid, ec_id):

    """Find a free IPv4 address for an instance.

    """

    nobj = self._UnlockedGetNetwork(net_uuid)

    pool = network.AddressPool(nobj)

    def gen_one():

      try:

        ip = pool.GenerateFree()

      except errors.AddressPoolError:

        raise errors.ReservationError("Cannot generate IP. Network is full")

      return (constants.RESERVE_ACTION, ip, net_uuid)

    _, address, _ = self._temporary_ips.Generate([], gen_one, ec_id)

    return address

  def _UnlockedReserveIp(self, net_uuid, address, ec_id, check=True):

    """Reserve a given IPv4 address for use by an instance.

    """

    nobj = self._UnlockedGetNetwork(net_uuid)

    pool = network.AddressPool(nobj)

    try:

      isreserved = pool.IsReserved(address)

      isextreserved = pool.IsReserved(address, external=True)

    except errors.AddressPoolError:

      raise errors.ReservationError("IP address not in network")

    if isreserved:

      raise errors.ReservationError("IP address already in use")

    if check and isextreserved:

      raise errors.ReservationError("IP is externally reserved")

    return self._temporary_ips.Reserve(ec_id,

                                       (constants.RESERVE_ACTION,

                                        address, net_uuid))

  @locking.ssynchronized(_config_lock, shared=1)

  def ReserveIp(self, net_uuid, address, ec_id, check=True):

    """Reserve a given IPv4 address for use by an instance.

    """

    if net_uuid:

      return self._UnlockedReserveIp(net_uuid, address, ec_id, check)

  @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 = self._UnlockedGetInstanceLVsByNode(instance)

      for lv_list in node_data.values():

        lvnames.update(lv_list)

    return lvnames

  def _AllDisks(self):

    """Compute the list of all Disks (recursively, including children).

    """

    def DiskAndAllChildren(disk):

      """Returns a list containing the given disk and all of his children.

      """

      disks = [disk]

      if disk.children:

        for child_disk in disk.children:

          disks.extend(DiskAndAllChildren(child_disk))

      return disks

    disks = []

    for instance in self._config_data.instances.values():

      for disk in instance.disks:

        disks.extend(DiskAndAllChildren(disk))

    return disks

  def _AllNICs(self):

    """Compute the list of all NICs.

    """

    nics = []

    for instance in self._config_data.instances.values():

      nics.extend(instance.nics)

    return nics

  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):

    """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

    @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.children:

      for child in disk.children:

        result.extend(self._CheckDiskIDs(child, l_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 = []

    # 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" %

                    utils.CommaJoin(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 not cluster.enabled_disk_templates:

      result.append("enabled disk templates list doesn't have any entries")

    invalid_disk_templates = set(cluster.enabled_disk_templates) \

                               - constants.DISK_TEMPLATES

    if invalid_disk_templates:

      result.append("enabled disk templates list contains invalid entries:"

                    " %s" % utils.CommaJoin(invalid_disk_templates))

    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))