X-Git-Url: https://code.grnet.gr/git/ganeti-local/blobdiff_plain/89ff8e15ca808f49233c015962ae24aedf7561cc..0b38cf6e7025dc90515391e074cfd25aac012f67:/lib/config.py

diff --git a/lib/config.py b/lib/config.py
index f5f9ea0..57c56d8 100644
--- a/lib/config.py
+++ b/lib/config.py
@@ -34,13 +34,26 @@ much memory.
 import os
 import tempfile
 import random
+import logging
 
 from ganeti import errors
-from ganeti import logger
+from ganeti import locking
 from ganeti import utils
 from ganeti import constants
 from ganeti import rpc
 from ganeti import objects
+from ganeti import serializer
+
+
+_config_lock = locking.SharedLock()
+
+
+def _ValidateConfig(data):
+  if data.version != constants.CONFIG_VERSION:
+    raise errors.ConfigurationError("Cluster configuration version"
+                                    " mismatch, got %s instead of %s" %
+                                    (data.version,
+                                     constants.CONFIG_VERSION))
 
 
 class ConfigWriter:
@@ -49,6 +62,7 @@ class ConfigWriter:
   """
   def __init__(self, cfg_file=None, offline=False):
     self.write_count = 0
+    self._lock = _config_lock
     self._config_data = None
     self._config_time = None
     self._config_size = None
@@ -59,6 +73,7 @@ class ConfigWriter:
     else:
       self._cfg_file = cfg_file
     self._temporary_ids = set()
+    self._temporary_drbds = {}
     # 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
@@ -73,6 +88,7 @@ class ConfigWriter:
     """
     return os.path.exists(constants.CLUSTER_CONF_FILE)
 
+  @locking.ssynchronized(_config_lock, shared=1)
   def GenerateMAC(self):
     """Generate a MAC for an instance.
 
@@ -80,7 +96,6 @@ class ConfigWriter:
 
     """
     self._OpenConfig()
-    self._ReleaseLock()
     prefix = self._config_data.cluster.mac_prefix
     all_macs = self._AllMACs()
     retries = 64
@@ -96,6 +111,7 @@ class ConfigWriter:
       raise errors.ConfigurationError("Can't generate unique MAC")
     return mac
 
+  @locking.ssynchronized(_config_lock, shared=1)
   def IsMacInUse(self, mac):
     """Predicate: check if the specified MAC is in use in the Ganeti cluster.
 
@@ -104,16 +120,33 @@ class ConfigWriter:
 
     """
     self._OpenConfig()
-    self._ReleaseLock()
     all_macs = self._AllMACs()
     return mac in all_macs
 
+  @locking.ssynchronized(_config_lock, shared=1)
+  def GenerateDRBDSecret(self):
+    """Generate a DRBD secret.
+
+    This checks the current disks for duplicates.
+
+    """
+    self._OpenConfig()
+    all_secrets = self._AllDRBDSecrets()
+    retries = 64
+    while retries > 0:
+      secret = utils.GenerateSecret()
+      if secret not in all_secrets:
+        break
+      retries -= 1
+    else:
+      raise errors.ConfigurationError("Can't generate unique DRBD secret")
+    return secret
+
   def _ComputeAllLVs(self):
     """Compute the list of all LVs.
 
     """
     self._OpenConfig()
-    self._ReleaseLock()
     lvnames = set()
     for instance in self._config_data.instances.values():
       node_data = instance.MapLVsByNode()
@@ -121,6 +154,7 @@ class ConfigWriter:
         lvnames.update(lv_list)
     return lvnames
 
+  @locking.ssynchronized(_config_lock, shared=1)
   def GenerateUniqueID(self, exceptions=None):
     """Generate an unique disk name.
 
@@ -159,7 +193,6 @@ class ConfigWriter:
 
     """
     self._OpenConfig()
-    self._ReleaseLock()
 
     result = []
     for instance in self._config_data.instances.values():
@@ -168,14 +201,34 @@ class ConfigWriter:
 
     return result
 
+  def _AllDRBDSecrets(self):
+    """Return all DRBD secrets present in the config.
+
+    """
+    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
+
+  @locking.ssynchronized(_config_lock, shared=1)
   def VerifyConfig(self):
     """Stub verify function.
     """
     self._OpenConfig()
-    self._ReleaseLock()
 
     result = []
     seen_macs = []
+    ports = {}
     data = self._config_data
     for instance_name in data.instances:
       instance = data.instances[instance_name]
@@ -192,9 +245,46 @@ class ConfigWriter:
                         (instance_name, idx, nic.mac))
         else:
           seen_macs.append(nic.mac)
+
+      # gather the drbd ports for duplicate checks
+      for dsk in 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" % dsk.iv_name))
+      # 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"))
+
+    # cluster-wide pool of free ports
+    for free_port in self._config_data.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 = ", ".join(["%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] > self._config_data.cluster.highest_used_port:
+        result.append("Highest used port mismatch, saved %s, computed %s" %
+                      (self._config_data.cluster.highest_used_port,
+                       keys[-1]))
+
     return result
 
-  def SetDiskID(self, disk, node_name):
+  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.
@@ -203,33 +293,49 @@ class ConfigWriter:
     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.SetDiskID(child, node_name)
+        self._UnlockedSetDiskID(child, node_name)
 
     if disk.logical_id is None and disk.physical_id is not None:
       return
-    if disk.dev_type in constants.LDS_DRBD:
-      pnode, snode, port = disk.logical_id
+    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.GetNodeInfo(pnode)
-      snode_info = self.GetNodeInfo(snode)
+      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 = (pnode_info.secondary_ip, port,
-                            snode_info.secondary_ip, port)
+        disk.physical_id = p_data + s_data + (pminor, secret)
       else: # it must be secondary, we tested above
-        disk.physical_id = (snode_info.secondary_ip, port,
-                            pnode_info.secondary_ip, port)
+        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.
 
@@ -241,14 +347,15 @@ class ConfigWriter:
     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.
 
     """
     self._OpenConfig()
-    self._ReleaseLock()
     return self._config_data.cluster.tcpudp_port_pool.copy()
 
+  @locking.ssynchronized(_config_lock)
   def AllocatePort(self):
     """Allocate a port.
 
@@ -273,6 +380,158 @@ class ConfigWriter:
     self._WriteConfig()
     return port
 
+  def _ComputeDRBDMap(self, instance):
+    """Compute the used DRBD minor/nodes.
+
+    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).
+
+    """
+    def _AppendUsedPorts(instance_name, disk, used):
+      if disk.dev_type == constants.LD_DRBD8 and len(disk.logical_id) >= 5:
+        nodeA, nodeB, dummy, minorA, minorB = disk.logical_id[:5]
+        for node, port in ((nodeA, minorA), (nodeB, minorB)):
+          assert node in used, "Instance node not found in node list"
+          if port in used[node]:
+            raise errors.ProgrammerError("DRBD minor already used:"
+                                         " %s/%s, %s/%s" %
+                                         (node, port, instance_name,
+                                          used[node][port]))
+
+          used[node][port] = instance_name
+      if disk.children:
+        for child in disk.children:
+          _AppendUsedPorts(instance_name, child, used)
+
+    my_dict = dict((node, {}) for node in self._config_data.nodes)
+    for (node, minor), instance in self._temporary_drbds.iteritems():
+      my_dict[node][minor] = instance
+    for instance in self._config_data.instances.itervalues():
+      for disk in instance.disks:
+        _AppendUsedPorts(instance.name, disk, my_dict)
+    return my_dict
+
+  @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.
+
+    """
+    self._OpenConfig()
+
+    d_map = self._ComputeDRBDMap(instance)
+    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
+      result.append(minor)
+      ndata[minor] = instance
+      assert (nname, minor) not in self._temporary_drbds, \
+             "Attempt to reuse reserved DRBD minor"
+      self._temporary_drbds[(nname, minor)] = instance
+    logging.debug("Request to allocate drbd minors, input: %s, returning %s",
+                  nodes, result)
+    return result
+
+  @locking.ssynchronized(_config_lock)
+  def ReleaseDRBDMinors(self, instance):
+    """Release temporary drbd minors allocated for a given instance.
+
+    This should be called on both the error paths and on the success
+    paths (after the instance has been added or updated).
+
+    @type instance: string
+    @param instance: the instance for which temporary minors should be
+                     released
+
+    """
+    for key, name in self._temporary_drbds.items():
+      if name == instance:
+        del self._temporary_drbds[key]
+
+  @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
+
+    """
+    self._OpenConfig()
+    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
+
+    """
+    self._OpenConfig()
+    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
+
+    """
+    self._OpenConfig()
+    return self._config_data.cluster.master_ip
+
+  @locking.ssynchronized(_config_lock, shared=1)
+  def GetMasterNetdev(self):
+    """Get the master network device for this cluster.
+
+    """
+    self._OpenConfig()
+    return self._config_data.cluster.master_netdev
+
+  @locking.ssynchronized(_config_lock, shared=1)
+  def GetFileStorageDir(self):
+    """Get the file storage dir for this cluster.
+
+    """
+    self._OpenConfig()
+    return self._config_data.cluster.file_storage_dir
+
+  @locking.ssynchronized(_config_lock, shared=1)
+  def GetHypervisorType(self):
+    """Get the hypervisor type for this cluster.
+
+    """
+    self._OpenConfig()
+    return self._config_data.cluster.hypervisor
+
+  @locking.ssynchronized(_config_lock, shared=1)
   def GetHostKey(self):
     """Return the rsa hostkey from the config.
 
@@ -281,9 +540,9 @@ class ConfigWriter:
     Returns: rsa hostkey
     """
     self._OpenConfig()
-    self._ReleaseLock()
     return self._config_data.cluster.rsahostkeypub
 
+  @locking.ssynchronized(_config_lock)
   def AddInstance(self, instance):
     """Add an instance to the config.
 
@@ -297,25 +556,41 @@ class ConfigWriter:
 
     if instance.disk_template != constants.DT_DISKLESS:
       all_lvs = instance.MapLVsByNode()
-      logger.Info("Instance '%s' DISK_LAYOUT: %s" % (instance.name, all_lvs))
+      logging.info("Instance '%s' DISK_LAYOUT: %s", instance.name, all_lvs)
 
     self._OpenConfig()
+    instance.serial_no = 1
     self._config_data.instances[instance.name] = instance
+    self._config_data.cluster.serial_no += 1
     self._WriteConfig()
 
-  def MarkInstanceUp(self, instance_name):
-    """Mark the instance status to up in the config.
+  def _SetInstanceStatus(self, instance_name, status):
+    """Set the instance's status to a given value.
 
     """
+    if status not in ("up", "down"):
+      raise errors.ProgrammerError("Invalid status '%s' passed to"
+                                   " ConfigWriter._SetInstanceStatus()" %
+                                   status)
     self._OpenConfig()
 
     if instance_name not in self._config_data.instances:
       raise errors.ConfigurationError("Unknown instance '%s'" %
                                       instance_name)
     instance = self._config_data.instances[instance_name]
-    instance.status = "up"
-    self._WriteConfig()
+    if instance.status != status:
+      instance.status = status
+      instance.serial_no += 1
+      self._WriteConfig()
 
+  @locking.ssynchronized(_config_lock)
+  def MarkInstanceUp(self, instance_name):
+    """Mark the instance status to up in the config.
+
+    """
+    self._SetInstanceStatus(instance_name, "up")
+
+  @locking.ssynchronized(_config_lock)
   def RemoveInstance(self, instance_name):
     """Remove the instance from the configuration.
 
@@ -325,8 +600,10 @@ class ConfigWriter:
     if instance_name not in self._config_data.instances:
       raise errors.ConfigurationError("Unknown instance '%s'" % instance_name)
     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.
 
@@ -341,21 +618,37 @@ class ConfigWriter:
     inst = self._config_data.instances[old_name]
     del self._config_data.instances[old_name]
     inst.name = new_name
+
+    for disk in 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.physical_id = disk.logical_id = (disk.logical_id[0],
+                                              os.path.join(file_storage_dir,
+                                                           inst.name,
+                                                           disk.iv_name))
+
     self._config_data.instances[inst.name] = inst
+    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._OpenConfig()
+    self._SetInstanceStatus(instance_name, "down")
 
-    if instance_name not in self._config_data.instances:
-      raise errors.ConfigurationError("Unknown instance '%s'" % instance_name)
-    instance = self._config_data.instances[instance_name]
-    instance.status = "down"
-    self._WriteConfig()
+  def _UnlockedGetInstanceList(self):
+    """Get the list of instances.
+
+    This function is for internal use, when the config lock is already held.
+
+    """
+    self._OpenConfig()
+    return self._config_data.instances.keys()
 
+  @locking.ssynchronized(_config_lock, shared=1)
   def GetInstanceList(self):
     """Get the list of instances.
 
@@ -364,21 +657,32 @@ class ConfigWriter:
       these contains all the instances, also the ones in Admin_down state
 
     """
-    self._OpenConfig()
-    self._ReleaseLock()
-
-    return self._config_data.instances.keys()
+    return self._UnlockedGetInstanceList()
 
+  @locking.ssynchronized(_config_lock, shared=1)
   def ExpandInstanceName(self, short_name):
     """Attempt to expand an incomplete instance name.
 
     """
     self._OpenConfig()
-    self._ReleaseLock()
 
     return utils.MatchNameComponent(short_name,
                                     self._config_data.instances.keys())
 
+  def _UnlockedGetInstanceInfo(self, instance_name):
+    """Returns informations about an instance.
+
+    This function is for internal use, when the config lock is already held.
+
+    """
+    self._OpenConfig()
+
+    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 informations about an instance.
 
@@ -392,14 +696,22 @@ class ConfigWriter:
       the instance object
 
     """
-    self._OpenConfig()
-    self._ReleaseLock()
+    return self._UnlockedGetInstanceInfo(instance_name)
 
-    if instance_name not in self._config_data.instances:
-      return None
+  @locking.ssynchronized(_config_lock, shared=1)
+  def GetAllInstancesInfo(self):
+    """Get the configuration of all instances.
 
-    return self._config_data.instances[instance_name]
+    @rtype: dict
+    @returns: 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)
   def AddNode(self, node):
     """Add a node to the configuration.
 
@@ -407,67 +719,103 @@ class ConfigWriter:
       node: an object.Node instance
 
     """
+    logging.info("Adding node %s to configuration" % node.name)
+
     self._OpenConfig()
+    node.serial_no = 1
     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)
+
     self._OpenConfig()
     if node_name not in self._config_data.nodes:
       raise errors.ConfigurationError("Unknown node '%s'" % node_name)
 
     del self._config_data.nodes[node_name]
+    self._config_data.cluster.serial_no += 1
     self._WriteConfig()
 
+  @locking.ssynchronized(_config_lock, shared=1)
   def ExpandNodeName(self, short_name):
     """Attempt to expand an incomplete instance name.
 
     """
     self._OpenConfig()
-    self._ReleaseLock()
 
     return utils.MatchNameComponent(short_name,
                                     self._config_data.nodes.keys())
 
-  def GetNodeInfo(self, node_name):
+  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.
+
     Args: node: nodename (tuple) of the node
 
     Returns: the node object
 
     """
     self._OpenConfig()
-    self._ReleaseLock()
 
     if node_name not in self._config_data.nodes:
       return None
 
     return self._config_data.nodes[node_name]
 
-  def GetNodeList(self):
+
+  @locking.ssynchronized(_config_lock, shared=1)
+  def GetNodeInfo(self, node_name):
+    """Get the configuration of a node, as stored in the config.
+
+    Args: node: nodename (tuple) of the node
+
+    Returns: the node object
+
+    """
+    return self._UnlockedGetNodeInfo(node_name)
+
+  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.
+
     """
     self._OpenConfig()
-    self._ReleaseLock()
     return self._config_data.nodes.keys()
 
-  def DumpConfig(self):
-    """Return the entire configuration of the cluster.
+
+  @locking.ssynchronized(_config_lock, shared=1)
+  def GetNodeList(self):
+    """Return the list of nodes which are in the configuration.
+
     """
-    self._OpenConfig()
-    self._ReleaseLock()
-    return self._config_data
+    return self._UnlockedGetNodeList()
+
+  @locking.ssynchronized(_config_lock, shared=1)
+  def GetAllNodesInfo(self):
+    """Get the configuration of all nodes.
+
+    @rtype: dict
+    @returns: dict of (node, node_info), where node_info is what
+              would GetNodeInfo return for the node
+
+    """
+    my_dict = dict([(node, self._UnlockedGetNodeInfo(node))
+                    for node in self._UnlockedGetNodeList()])
+    return my_dict
 
   def _BumpSerialNo(self):
     """Bump up the serial number of the config.
 
     """
-    self._config_data.cluster.serial_no += 1
+    self._config_data.serial_no += 1
 
   def _OpenConfig(self):
     """Read the config data from disk.
@@ -488,32 +836,28 @@ class ConfigWriter:
         self._config_inode == st.st_ino):
       # data is current, so skip loading of config file
       return
+
     f = open(self._cfg_file, 'r')
     try:
       try:
-        data = objects.ConfigData.Load(f)
+        data = objects.ConfigData.FromDict(serializer.Load(f.read()))
       except Exception, err:
         raise errors.ConfigurationError(err)
     finally:
       f.close()
+
+    # Make sure the configuration has the right version
+    _ValidateConfig(data)
+
     if (not hasattr(data, 'cluster') or
-        not hasattr(data.cluster, 'config_version')):
+        not hasattr(data.cluster, 'rsahostkeypub')):
       raise errors.ConfigurationError("Incomplete configuration"
-                                      " (missing cluster.config_version)")
-    if data.cluster.config_version != constants.CONFIG_VERSION:
-      raise errors.ConfigurationError("Cluster configuration version"
-                                      " mismatch, got %s instead of %s" %
-                                      (data.cluster.config_version,
-                                       constants.CONFIG_VERSION))
+                                      " (missing cluster.rsahostkeypub)")
     self._config_data = data
     self._config_time = st.st_mtime
     self._config_size = st.st_size
     self._config_inode = st.st_ino
 
-  def _ReleaseLock(self):
-    """xxxx
-    """
-
   def _DistributeConfig(self):
     """Distribute the configuration to the other nodes.
 
@@ -524,21 +868,19 @@ class ConfigWriter:
     if self._offline:
       return True
     bad = False
-    nodelist = self.GetNodeList()
+    nodelist = self._UnlockedGetNodeList()
     myhostname = self._my_hostname
 
-    tgt_list = []
-    for node in nodelist:
-      nodeinfo = self.GetNodeInfo(node)
-      if nodeinfo.name == myhostname:
-        continue
-      tgt_list.append(node)
+    try:
+      nodelist.remove(myhostname)
+    except ValueError:
+      pass
 
-    result = rpc.call_upload_file(tgt_list, self._cfg_file)
-    for node in tgt_list:
+    result = rpc.call_upload_file(nodelist, self._cfg_file)
+    for node in nodelist:
       if not result[node]:
-        logger.Error("copy of file %s to node %s failed" %
-                     (self._cfg_file, node))
+        logging.error("copy of file %s to node %s failed",
+                      self._cfg_file, node)
         bad = True
     return not bad
 
@@ -549,11 +891,12 @@ class ConfigWriter:
     if destination is None:
       destination = self._cfg_file
     self._BumpSerialNo()
+    txt = serializer.Dump(self._config_data.ToDict())
     dir_name, file_name = os.path.split(destination)
     fd, name = tempfile.mkstemp('.newconfig', file_name, dir_name)
     f = os.fdopen(fd, 'w')
     try:
-      self._config_data.Dump(f)
+      f.write(txt)
       os.fsync(f.fileno())
     finally:
       f.close()
@@ -571,71 +914,67 @@ class ConfigWriter:
     # and redistribute the config file
     self._DistributeConfig()
 
-  def InitConfig(self, node, primary_ip, secondary_ip,
-                 hostkeypub, mac_prefix, vg_name, def_bridge):
+  @locking.ssynchronized(_config_lock)
+  def InitConfig(self, version, cluster_config, master_node_config):
     """Create the initial cluster configuration.
 
     It will contain the current node, which will also be the master
-    node, and no instances or operating systmes.
+    node, and no instances.
 
-    Args:
-      node: the nodename of the initial node
-      primary_ip: the IP address of the current host
-      secondary_ip: the secondary IP of the current host or None
-      hostkeypub: the public hostkey of this host
-
-    """
-    hu_port = constants.FIRST_DRBD_PORT - 1
-    globalconfig = objects.Cluster(config_version=constants.CONFIG_VERSION,
-                                   serial_no=1,
-                                   rsahostkeypub=hostkeypub,
-                                   highest_used_port=hu_port,
-                                   mac_prefix=mac_prefix,
-                                   volume_group_name=vg_name,
-                                   default_bridge=def_bridge,
-                                   tcpudp_port_pool=set())
-    if secondary_ip is None:
-      secondary_ip = primary_ip
-    nodeconfig = objects.Node(name=node, primary_ip=primary_ip,
-                              secondary_ip=secondary_ip)
-
-    self._config_data = objects.ConfigData(nodes={node: nodeconfig},
+    @type version: int
+    @param version: Configuration version
+    @type cluster_config: objects.Cluster
+    @param cluster_config: Cluster configuration
+    @type master_node_config: objects.Node
+    @param master_node_config: Master node configuration
+
+    """
+    nodes = {
+      master_node_config.name: master_node_config,
+      }
+
+    self._config_data = objects.ConfigData(version=version,
+                                           cluster=cluster_config,
+                                           nodes=nodes,
                                            instances={},
-                                           cluster=globalconfig)
+                                           serial_no=1)
     self._WriteConfig()
 
+  @locking.ssynchronized(_config_lock, shared=1)
   def GetVGName(self):
     """Return the volume group name.
 
     """
     self._OpenConfig()
-    self._ReleaseLock()
     return self._config_data.cluster.volume_group_name
 
+  @locking.ssynchronized(_config_lock)
   def SetVGName(self, vg_name):
     """Set the volume group name.
 
     """
     self._OpenConfig()
-    self._config_data.cluster["volume_group_name"] = vg_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 GetDefBridge(self):
     """Return the default bridge.
 
     """
     self._OpenConfig()
-    self._ReleaseLock()
     return self._config_data.cluster.default_bridge
 
+  @locking.ssynchronized(_config_lock, shared=1)
   def GetMACPrefix(self):
     """Return the mac prefix.
 
     """
     self._OpenConfig()
-    self._ReleaseLock()
     return self._config_data.cluster.mac_prefix
 
+  @locking.ssynchronized(_config_lock, shared=1)
   def GetClusterInfo(self):
     """Returns informations about the cluster
 
@@ -644,10 +983,10 @@ class ConfigWriter:
 
     """
     self._OpenConfig()
-    self._ReleaseLock()
 
     return self._config_data.cluster
 
+  @locking.ssynchronized(_config_lock)
   def Update(self, target):
     """Notify function to be called after updates.
 
@@ -673,4 +1012,6 @@ class ConfigWriter:
     if not test:
       raise errors.ConfigurationError("Configuration updated since object"
                                       " has been read or unknown object")
+    target.serial_no += 1
+
     self._WriteConfig()