Merge branch 'stable-2.1' into devel-2.1
[ganeti-local] / lib / cmdlib.py
index c2187eb..cb922eb 100644 (file)
 
 """Module implementing the master-side code."""
 
-# pylint: disable-msg=W0613,W0201
+# pylint: disable-msg=W0201
+
+# W0201 since most LU attributes are defined in CheckPrereq or similar
+# functions
 
 import os
 import os.path
@@ -87,9 +90,9 @@ class LogicalUnit(object):
     self.recalculate_locks = {}
     self.__ssh = None
     # logging
-    self.LogWarning = processor.LogWarning
-    self.LogInfo = processor.LogInfo
-    self.LogStep = processor.LogStep
+    self.LogWarning = processor.LogWarning # pylint: disable-msg=C0103
+    self.LogInfo = processor.LogInfo # pylint: disable-msg=C0103
+    self.LogStep = processor.LogStep # pylint: disable-msg=C0103
     # support for dry-run
     self.dry_run_result = None
 
@@ -100,7 +103,7 @@ class LogicalUnit(object):
       attr_val = getattr(op, attr_name, None)
       if attr_val is None:
         raise errors.OpPrereqError("Required parameter '%s' missing" %
-                                   attr_name)
+                                   attr_name, errors.ECODE_INVAL)
 
     self.CheckArguments()
 
@@ -277,6 +280,9 @@ class LogicalUnit(object):
         and hook results
 
     """
+    # API must be kept, thus we ignore the unused argument and could
+    # be a function warnings
+    # pylint: disable-msg=W0613,R0201
     return lu_result
 
   def _ExpandAndLockInstance(self):
@@ -297,7 +303,7 @@ class LogicalUnit(object):
     expanded_name = self.cfg.ExpandInstanceName(self.op.instance_name)
     if expanded_name is None:
       raise errors.OpPrereqError("Instance '%s' not known" %
-                                  self.op.instance_name)
+                                 self.op.instance_name, errors.ECODE_NOENT)
     self.needed_locks[locking.LEVEL_INSTANCE] = expanded_name
     self.op.instance_name = expanded_name
 
@@ -347,7 +353,7 @@ class LogicalUnit(object):
     del self.recalculate_locks[locking.LEVEL_NODE]
 
 
-class NoHooksLU(LogicalUnit):
+class NoHooksLU(LogicalUnit): # pylint: disable-msg=W0223
   """Simple LU which runs no hooks.
 
   This LU is intended as a parent for other LogicalUnits which will
@@ -357,6 +363,14 @@ class NoHooksLU(LogicalUnit):
   HPATH = None
   HTYPE = None
 
+  def BuildHooksEnv(self):
+    """Empty BuildHooksEnv for NoHooksLu.
+
+    This just raises an error.
+
+    """
+    assert False, "BuildHooksEnv called for NoHooksLUs"
+
 
 class Tasklet:
   """Tasklet base class.
@@ -417,7 +431,8 @@ def _GetWantedNodes(lu, nodes):
 
   """
   if not isinstance(nodes, list):
-    raise errors.OpPrereqError("Invalid argument type 'nodes'")
+    raise errors.OpPrereqError("Invalid argument type 'nodes'",
+                               errors.ECODE_INVAL)
 
   if not nodes:
     raise errors.ProgrammerError("_GetWantedNodes should only be called with a"
@@ -427,7 +442,8 @@ def _GetWantedNodes(lu, nodes):
   for name in nodes:
     node = lu.cfg.ExpandNodeName(name)
     if node is None:
-      raise errors.OpPrereqError("No such node name '%s'" % name)
+      raise errors.OpPrereqError("No such node name '%s'" % name,
+                                 errors.ECODE_NOENT)
     wanted.append(node)
 
   return utils.NiceSort(wanted)
@@ -447,7 +463,8 @@ def _GetWantedInstances(lu, instances):
 
   """
   if not isinstance(instances, list):
-    raise errors.OpPrereqError("Invalid argument type 'instances'")
+    raise errors.OpPrereqError("Invalid argument type 'instances'",
+                               errors.ECODE_INVAL)
 
   if instances:
     wanted = []
@@ -455,7 +472,8 @@ def _GetWantedInstances(lu, instances):
     for name in instances:
       instance = lu.cfg.ExpandInstanceName(name)
       if instance is None:
-        raise errors.OpPrereqError("No such instance name '%s'" % name)
+        raise errors.OpPrereqError("No such instance name '%s'" % name,
+                                   errors.ECODE_NOENT)
       wanted.append(instance)
 
   else:
@@ -479,7 +497,7 @@ def _CheckOutputFields(static, dynamic, selected):
   delta = f.NonMatching(selected)
   if delta:
     raise errors.OpPrereqError("Unknown output fields selected: %s"
-                               % ",".join(delta))
+                               % ",".join(delta), errors.ECODE_INVAL)
 
 
 def _CheckBooleanOpField(op, name):
@@ -492,10 +510,25 @@ def _CheckBooleanOpField(op, name):
   val = getattr(op, name, None)
   if not (val is None or isinstance(val, bool)):
     raise errors.OpPrereqError("Invalid boolean parameter '%s' (%s)" %
-                               (name, str(val)))
+                               (name, str(val)), errors.ECODE_INVAL)
   setattr(op, name, val)
 
 
+def _CheckGlobalHvParams(params):
+  """Validates that given hypervisor params are not global ones.
+
+  This will ensure that instances don't get customised versions of
+  global params.
+
+  """
+  used_globals = constants.HVC_GLOBALS.intersection(params)
+  if used_globals:
+    msg = ("The following hypervisor parameters are global and cannot"
+           " be customized at instance level, please modify them at"
+           " cluster level: %s" % utils.CommaJoin(used_globals))
+    raise errors.OpPrereqError(msg, errors.ECODE_INVAL)
+
+
 def _CheckNodeOnline(lu, node):
   """Ensure that a given node is online.
 
@@ -505,7 +538,8 @@ def _CheckNodeOnline(lu, node):
 
   """
   if lu.cfg.GetNodeInfo(node).offline:
-    raise errors.OpPrereqError("Can't use offline node %s" % node)
+    raise errors.OpPrereqError("Can't use offline node %s" % node,
+                               errors.ECODE_INVAL)
 
 
 def _CheckNodeNotDrained(lu, node):
@@ -517,7 +551,8 @@ def _CheckNodeNotDrained(lu, node):
 
   """
   if lu.cfg.GetNodeInfo(node).drained:
-    raise errors.OpPrereqError("Can't use drained node %s" % node)
+    raise errors.OpPrereqError("Can't use drained node %s" % node,
+                               errors.ECODE_INVAL)
 
 
 def _BuildInstanceHookEnv(name, primary_node, secondary_nodes, os_type, status,
@@ -667,7 +702,7 @@ def _BuildInstanceHookEnvByObject(lu, instance, override=None):
   }
   if override:
     args.update(override)
-  return _BuildInstanceHookEnv(**args)
+  return _BuildInstanceHookEnv(**args) # pylint: disable-msg=W0142
 
 
 def _AdjustCandidatePool(lu, exceptions):
@@ -677,7 +712,7 @@ def _AdjustCandidatePool(lu, exceptions):
   mod_list = lu.cfg.MaintainCandidatePool(exceptions)
   if mod_list:
     lu.LogInfo("Promoted nodes to master candidate role: %s",
-               ", ".join(node.name for node in mod_list))
+               utils.CommaJoin(node.name for node in mod_list))
     for name in mod_list:
       lu.context.ReaddNode(name)
   mc_now, mc_max, _ = lu.cfg.GetMasterCandidateStats(exceptions)
@@ -710,7 +745,7 @@ def _CheckNicsBridgesExist(lu, target_nics, target_node,
   if brlist:
     result = lu.rpc.call_bridges_exist(target_node, brlist)
     result.Raise("Error checking bridges on destination node '%s'" %
-                 target_node, prereq=True)
+                 target_node, prereq=True, ecode=errors.ECODE_ENVIRON)
 
 
 def _CheckInstanceBridgesExist(lu, instance, node=None):
@@ -736,10 +771,11 @@ def _CheckOSVariant(os_obj, name):
   try:
     variant = name.split("+", 1)[1]
   except IndexError:
-    raise errors.OpPrereqError("OS name must include a variant")
+    raise errors.OpPrereqError("OS name must include a variant",
+                               errors.ECODE_INVAL)
 
   if variant not in os_obj.supported_variants:
-    raise errors.OpPrereqError("Unsupported OS variant")
+    raise errors.OpPrereqError("Unsupported OS variant", errors.ECODE_INVAL)
 
 
 def _GetNodeInstancesInner(cfg, fn):
@@ -790,7 +826,7 @@ def _FindFaultyInstanceDisks(cfg, rpc, instance, node_name, prereq):
 
   result = rpc.call_blockdev_getmirrorstatus(node_name, instance.disks)
   result.Raise("Failed to get disk status from node %s" % node_name,
-               prereq=prereq)
+               prereq=prereq, ecode=errors.ECODE_ENVIRON)
 
   for idx, bdev_status in enumerate(result.payload):
     if bdev_status and bdev_status.ldisk_status == constants.LDS_FAULTY:
@@ -856,11 +892,13 @@ class LUDestroyCluster(LogicalUnit):
     nodelist = self.cfg.GetNodeList()
     if len(nodelist) != 1 or nodelist[0] != master:
       raise errors.OpPrereqError("There are still %d node(s) in"
-                                 " this cluster." % (len(nodelist) - 1))
+                                 " this cluster." % (len(nodelist) - 1),
+                                 errors.ECODE_INVAL)
     instancelist = self.cfg.GetInstanceList()
     if instancelist:
       raise errors.OpPrereqError("There are still %d instance(s) in"
-                                 " this cluster." % len(instancelist))
+                                 " this cluster." % len(instancelist),
+                                 errors.ECODE_INVAL)
 
   def Exec(self, feedback_fn):
     """Destroys the cluster.
@@ -874,6 +912,7 @@ class LUDestroyCluster(LogicalUnit):
     try:
       hm.RunPhase(constants.HOOKS_PHASE_POST, [master])
     except:
+      # pylint: disable-msg=W0702
       self.LogWarning("Errors occurred running hooks on %s" % master)
 
     result = self.rpc.call_node_stop_master(master, False)
@@ -920,6 +959,7 @@ class LUVerifyCluster(LogicalUnit):
   ENODESSH = (TNODE, "ENODESSH")
   ENODEVERSION = (TNODE, "ENODEVERSION")
   ENODESETUP = (TNODE, "ENODESETUP")
+  ENODETIME = (TNODE, "ENODETIME")
 
   ETYPE_FIELD = "code"
   ETYPE_ERROR = "ERROR"
@@ -993,7 +1033,7 @@ class LUVerifyCluster(LogicalUnit):
 
     """
     node = nodeinfo.name
-    _ErrorIf = self._ErrorIf
+    _ErrorIf = self._ErrorIf # pylint: disable-msg=C0103
 
     # main result, node_result should be a non-empty dict
     test = not node_result or not isinstance(node_result, dict)
@@ -1118,6 +1158,20 @@ class LUVerifyCluster(LogicalUnit):
     _ErrorIf(test, self.ENODESETUP, node, "node setup error: %s",
              "; ".join(test))
 
+    # check pv names
+    if vg_name is not None:
+      pvlist = node_result.get(constants.NV_PVLIST, None)
+      test = pvlist is None
+      _ErrorIf(test, self.ENODELVM, node, "Can't get PV list from node")
+      if not test:
+        # check that ':' is not present in PV names, since it's a
+        # special character for lvcreate (denotes the range of PEs to
+        # use on the PV)
+        for _, pvname, owner_vg in pvlist:
+          test = ":" in pvname
+          _ErrorIf(test, self.ENODELVM, node, "Invalid character ':' in PV"
+                   " '%s' of VG '%s'", pvname, owner_vg)
+
   def _VerifyInstance(self, instance, instanceconfig, node_vol_is,
                       node_instance, n_offline):
     """Verify an instance.
@@ -1126,7 +1180,7 @@ class LUVerifyCluster(LogicalUnit):
     available on the instance's node.
 
     """
-    _ErrorIf = self._ErrorIf
+    _ErrorIf = self._ErrorIf # pylint: disable-msg=C0103
     node_current = instanceconfig.primary_node
 
     node_vol_should = {}
@@ -1217,7 +1271,8 @@ class LUVerifyCluster(LogicalUnit):
     """
     self.skip_set = frozenset(self.op.skip_checks)
     if not constants.VERIFY_OPTIONAL_CHECKS.issuperset(self.skip_set):
-      raise errors.OpPrereqError("Invalid checks to be skipped specified")
+      raise errors.OpPrereqError("Invalid checks to be skipped specified",
+                                 errors.ECODE_INVAL)
 
   def BuildHooksEnv(self):
     """Build hooks env.
@@ -1240,7 +1295,7 @@ class LUVerifyCluster(LogicalUnit):
 
     """
     self.bad = False
-    _ErrorIf = self._ErrorIf
+    _ErrorIf = self._ErrorIf # pylint: disable-msg=C0103
     verbose = self.op.verbose
     self._feedback_fn = feedback_fn
     feedback_fn("* Verifying global settings")
@@ -1287,13 +1342,23 @@ class LUVerifyCluster(LogicalUnit):
       constants.NV_VERSION: None,
       constants.NV_HVINFO: self.cfg.GetHypervisorType(),
       constants.NV_NODESETUP: None,
+      constants.NV_TIME: None,
       }
+
     if vg_name is not None:
       node_verify_param[constants.NV_VGLIST] = None
       node_verify_param[constants.NV_LVLIST] = vg_name
+      node_verify_param[constants.NV_PVLIST] = [vg_name]
       node_verify_param[constants.NV_DRBDLIST] = None
+
+    # Due to the way our RPC system works, exact response times cannot be
+    # guaranteed (e.g. a broken node could run into a timeout). By keeping the
+    # time before and after executing the request, we can at least have a time
+    # window.
+    nvinfo_starttime = time.time()
     all_nvinfo = self.rpc.call_node_verify(nodelist, node_verify_param,
                                            self.cfg.GetClusterName())
+    nvinfo_endtime = time.time()
 
     cluster = self.cfg.GetClusterInfo()
     master_node = self.cfg.GetMasterNode()
@@ -1340,6 +1405,7 @@ class LUVerifyCluster(LogicalUnit):
         else:
           instance = instanceinfo[instance]
           node_drbd[minor] = (instance.name, instance.admin_up)
+
       self._VerifyNode(node_i, file_names, local_checksums,
                        nresult, master_files, node_drbd, vg_name)
 
@@ -1373,6 +1439,27 @@ class LUVerifyCluster(LogicalUnit):
       if test:
         continue
 
+      # Node time
+      ntime = nresult.get(constants.NV_TIME, None)
+      try:
+        ntime_merged = utils.MergeTime(ntime)
+      except (ValueError, TypeError):
+        _ErrorIf(test, self.ENODETIME, node, "Node returned invalid time")
+
+      if ntime_merged < (nvinfo_starttime - constants.NODE_MAX_CLOCK_SKEW):
+        ntime_diff = abs(nvinfo_starttime - ntime_merged)
+      elif ntime_merged > (nvinfo_endtime + constants.NODE_MAX_CLOCK_SKEW):
+        ntime_diff = abs(ntime_merged - nvinfo_endtime)
+      else:
+        ntime_diff = None
+
+      _ErrorIf(ntime_diff is not None, self.ENODETIME, node,
+               "Node time diverges by at least %0.1fs from master node time",
+               ntime_diff)
+
+      if ntime_diff is not None:
+        continue
+
       try:
         node_info[node] = {
           "mfree": int(nodeinfo['memory_free']),
@@ -1458,7 +1545,7 @@ class LUVerifyCluster(LogicalUnit):
       # warn that the instance lives on offline nodes
       _ErrorIf(inst_nodes_offline, self.EINSTANCEBADNODE, instance,
                "instance lives on offline node(s) %s",
-               ", ".join(inst_nodes_offline))
+               utils.CommaJoin(inst_nodes_offline))
 
     feedback_fn("* Verifying orphan volumes")
     self._VerifyOrphanVolumes(node_vol_should, node_volume)
@@ -1511,13 +1598,13 @@ class LUVerifyCluster(LogicalUnit):
       assert hooks_results, "invalid result from hooks"
 
       for node_name in hooks_results:
-        show_node_header = True
         res = hooks_results[node_name]
         msg = res.fail_msg
         test = msg and not res.offline
         self._ErrorIf(test, self.ENODEHOOKS, node_name,
                       "Communication failure in hooks execution: %s", msg)
-        if test:
+        if res.offline or msg:
+          # No need to investigate payload if node is offline or gave an error.
           # override manually lu_result here as _ErrorIf only
           # overrides self.bad
           lu_result = 1
@@ -1601,7 +1688,7 @@ class LUVerifyDisks(NoHooksLU):
         continue
 
       lvs = node_res.payload
-      for lv_name, (_, lv_inactive, lv_online) in lvs.items():
+      for lv_name, (_, _, lv_online) in lvs.items():
         inst = nv_dict.pop((node, lv_name), None)
         if (not lv_online and inst is not None
             and inst.name not in res_instances):
@@ -1626,14 +1713,16 @@ class LURepairDiskSizes(NoHooksLU):
 
   def ExpandNames(self):
     if not isinstance(self.op.instances, list):
-      raise errors.OpPrereqError("Invalid argument type 'instances'")
+      raise errors.OpPrereqError("Invalid argument type 'instances'",
+                                 errors.ECODE_INVAL)
 
     if self.op.instances:
       self.wanted_names = []
       for name in self.op.instances:
         full_name = self.cfg.ExpandInstanceName(name)
         if full_name is None:
-          raise errors.OpPrereqError("Instance '%s' not known" % name)
+          raise errors.OpPrereqError("Instance '%s' not known" % name,
+                                     errors.ECODE_NOENT)
         self.wanted_names.append(full_name)
       self.needed_locks = {
         locking.LEVEL_NODE: [],
@@ -1755,13 +1844,14 @@ class LURenameCluster(LogicalUnit):
       "NEW_NAME": self.op.name,
       }
     mn = self.cfg.GetMasterNode()
-    return env, [mn], [mn]
+    all_nodes = self.cfg.GetNodeList()
+    return env, [mn], all_nodes
 
   def CheckPrereq(self):
     """Verify that the passed name is a valid one.
 
     """
-    hostname = utils.HostInfo(self.op.name)
+    hostname = utils.GetHostInfo(self.op.name)
 
     new_name = hostname.name
     self.ip = new_ip = hostname.ip
@@ -1769,12 +1859,13 @@ class LURenameCluster(LogicalUnit):
     old_ip = self.cfg.GetMasterIP()
     if new_name == old_name and new_ip == old_ip:
       raise errors.OpPrereqError("Neither the name nor the IP address of the"
-                                 " cluster has changed")
+                                 " cluster has changed",
+                                 errors.ECODE_INVAL)
     if new_ip != old_ip:
       if utils.TcpPing(new_ip, constants.DEFAULT_NODED_PORT):
         raise errors.OpPrereqError("The given cluster IP address (%s) is"
                                    " reachable on the network. Aborting." %
-                                   new_ip)
+                                   new_ip, errors.ECODE_NOTUNIQUE)
 
     self.op.name = new_name
 
@@ -1856,9 +1947,10 @@ class LUSetClusterParams(LogicalUnit):
         self.op.candidate_pool_size = int(self.op.candidate_pool_size)
       except (ValueError, TypeError), err:
         raise errors.OpPrereqError("Invalid candidate_pool_size value: %s" %
-                                   str(err))
+                                   str(err), errors.ECODE_INVAL)
       if self.op.candidate_pool_size < 1:
-        raise errors.OpPrereqError("At least one master candidate needed")
+        raise errors.OpPrereqError("At least one master candidate needed",
+                                   errors.ECODE_INVAL)
 
   def ExpandNames(self):
     # FIXME: in the future maybe other cluster params won't require checking on
@@ -1892,7 +1984,8 @@ class LUSetClusterParams(LogicalUnit):
         for disk in inst.disks:
           if _RecursiveCheckIfLVMBased(disk):
             raise errors.OpPrereqError("Cannot disable lvm storage while"
-                                       " lvm-based instances exist")
+                                       " lvm-based instances exist",
+                                       errors.ECODE_INVAL)
 
     node_list = self.acquired_locks[locking.LEVEL_NODE]
 
@@ -1911,7 +2004,7 @@ class LUSetClusterParams(LogicalUnit):
                                               constants.MIN_VG_SIZE)
         if vgstatus:
           raise errors.OpPrereqError("Error on node '%s': %s" %
-                                     (node, vgstatus))
+                                     (node, vgstatus), errors.ECODE_ENVIRON)
 
     self.cluster = cluster = self.cfg.GetClusterInfo()
     # validate params changes
@@ -1925,12 +2018,36 @@ class LUSetClusterParams(LogicalUnit):
       self.new_nicparams = objects.FillDict(
         cluster.nicparams[constants.PP_DEFAULT], self.op.nicparams)
       objects.NIC.CheckParameterSyntax(self.new_nicparams)
+      nic_errors = []
+
+      # check all instances for consistency
+      for instance in self.cfg.GetAllInstancesInfo().values():
+        for nic_idx, nic in enumerate(instance.nics):
+          params_copy = copy.deepcopy(nic.nicparams)
+          params_filled = objects.FillDict(self.new_nicparams, params_copy)
+
+          # check parameter syntax
+          try:
+            objects.NIC.CheckParameterSyntax(params_filled)
+          except errors.ConfigurationError, err:
+            nic_errors.append("Instance %s, nic/%d: %s" %
+                              (instance.name, nic_idx, err))
+
+          # if we're moving instances to routed, check that they have an ip
+          target_mode = params_filled[constants.NIC_MODE]
+          if target_mode == constants.NIC_MODE_ROUTED and not nic.ip:
+            nic_errors.append("Instance %s, nic/%d: routed nick with no ip" %
+                              (instance.name, nic_idx))
+      if nic_errors:
+        raise errors.OpPrereqError("Cannot apply the change, errors:\n%s" %
+                                   "\n".join(nic_errors))
 
     # hypervisor list/parameters
     self.new_hvparams = objects.FillDict(cluster.hvparams, {})
     if self.op.hvparams:
       if not isinstance(self.op.hvparams, dict):
-        raise errors.OpPrereqError("Invalid 'hvparams' parameter on input")
+        raise errors.OpPrereqError("Invalid 'hvparams' parameter on input",
+                                   errors.ECODE_INVAL)
       for hv_name, hv_dict in self.op.hvparams.items():
         if hv_name not in self.new_hvparams:
           self.new_hvparams[hv_name] = hv_dict
@@ -1941,11 +2058,14 @@ class LUSetClusterParams(LogicalUnit):
       self.hv_list = self.op.enabled_hypervisors
       if not self.hv_list:
         raise errors.OpPrereqError("Enabled hypervisors list must contain at"
-                                   " least one member")
+                                   " least one member",
+                                   errors.ECODE_INVAL)
       invalid_hvs = set(self.hv_list) - constants.HYPER_TYPES
       if invalid_hvs:
         raise errors.OpPrereqError("Enabled hypervisors contains invalid"
-                                   " entries: %s" % " ,".join(invalid_hvs))
+                                   " entries: %s" %
+                                   utils.CommaJoin(invalid_hvs),
+                                   errors.ECODE_INVAL)
     else:
       self.hv_list = cluster.enabled_hypervisors
 
@@ -2063,7 +2183,7 @@ class LURedistributeConfig(NoHooksLU):
     _RedistributeAncillaryFiles(self)
 
 
-def _WaitForSync(lu, instance, oneshot=False, unlock=False):
+def _WaitForSync(lu, instance, oneshot=False):
   """Sleep and poll for an instance's disk to sync.
 
   """
@@ -2078,6 +2198,8 @@ def _WaitForSync(lu, instance, oneshot=False, unlock=False):
   for dev in instance.disks:
     lu.cfg.SetDiskID(dev, node)
 
+  # TODO: Convert to utils.Retry
+
   retries = 0
   degr_retries = 10 # in seconds, as we sleep 1 second each time
   while True:
@@ -2181,7 +2303,8 @@ class LUDiagnoseOS(NoHooksLU):
 
   def ExpandNames(self):
     if self.op.names:
-      raise errors.OpPrereqError("Selective OS query not supported")
+      raise errors.OpPrereqError("Selective OS query not supported",
+                                 errors.ECODE_INVAL)
 
     _CheckOutputFields(static=self._FIELDS_STATIC,
                        dynamic=self._FIELDS_DYNAMIC,
@@ -2200,10 +2323,9 @@ class LUDiagnoseOS(NoHooksLU):
     """
 
   @staticmethod
-  def _DiagnoseByOS(node_list, rlist):
+  def _DiagnoseByOS(rlist):
     """Remaps a per-node return list into an a per-os per-node dictionary
 
-    @param node_list: a list with the names of all nodes
     @param rlist: a map with node names as keys and OS objects as values
 
     @rtype: dict
@@ -2241,7 +2363,7 @@ class LUDiagnoseOS(NoHooksLU):
     """
     valid_nodes = [node for node in self.cfg.GetOnlineNodeList()]
     node_data = self.rpc.call_os_diagnose(valid_nodes)
-    pol = self._DiagnoseByOS(valid_nodes, node_data)
+    pol = self._DiagnoseByOS(node_data)
     output = []
     calc_valid = self._FIELDS_NEEDVALID.intersection(self.op.output_fields)
     calc_variants = "variants" in self.op.output_fields
@@ -2303,8 +2425,11 @@ class LURemoveNode(LogicalUnit):
       "NODE_NAME": self.op.node_name,
       }
     all_nodes = self.cfg.GetNodeList()
-    if self.op.node_name in all_nodes:
+    try:
       all_nodes.remove(self.op.node_name)
+    except ValueError:
+      logging.warning("Node %s which is about to be removed not found"
+                      " in the all nodes list", self.op.node_name)
     return env, all_nodes, all_nodes
 
   def CheckPrereq(self):
@@ -2320,20 +2445,23 @@ class LURemoveNode(LogicalUnit):
     """
     node = self.cfg.GetNodeInfo(self.cfg.ExpandNodeName(self.op.node_name))
     if node is None:
-      raise errors.OpPrereqError, ("Node '%s' is unknown." % self.op.node_name)
+      raise errors.OpPrereqError("Node '%s' is unknown." % self.op.node_name,
+                                 errors.ECODE_NOENT)
 
     instance_list = self.cfg.GetInstanceList()
 
     masternode = self.cfg.GetMasterNode()
     if node.name == masternode:
       raise errors.OpPrereqError("Node is the master node,"
-                                 " you need to failover first.")
+                                 " you need to failover first.",
+                                 errors.ECODE_INVAL)
 
     for instance_name in instance_list:
       instance = self.cfg.GetInstanceInfo(instance_name)
       if node.name in instance.all_nodes:
         raise errors.OpPrereqError("Instance %s is still running on the node,"
-                                   " please remove first." % instance_name)
+                                   " please remove first." % instance_name,
+                                   errors.ECODE_INVAL)
     self.op.node_name = node.name
     self.node = node
 
@@ -2354,8 +2482,9 @@ class LURemoveNode(LogicalUnit):
     # Run post hooks on the node before it's removed
     hm = self.proc.hmclass(self.rpc.call_hooks_runner, self)
     try:
-      h_results = hm.RunPhase(constants.HOOKS_PHASE_POST, [node.name])
+      hm.RunPhase(constants.HOOKS_PHASE_POST, [node.name])
     except:
+      # pylint: disable-msg=W0702
       self.LogWarning("Errors occurred running hooks on %s" % node.name)
 
     result = self.rpc.call_node_leave_cluster(node.name, modify_ssh_setup)
@@ -2369,6 +2498,7 @@ class LUQueryNodes(NoHooksLU):
   """Logical unit for querying nodes.
 
   """
+  # pylint: disable-msg=W0142
   _OP_REQP = ["output_fields", "names", "use_locking"]
   REQ_BGL = False
 
@@ -2469,10 +2599,9 @@ class LUQueryNodes(NoHooksLU):
     inst_fields = frozenset(("pinst_cnt", "pinst_list",
                              "sinst_cnt", "sinst_list"))
     if inst_fields & frozenset(self.op.output_fields):
-      instancelist = self.cfg.GetInstanceList()
+      inst_data = self.cfg.GetAllInstancesInfo()
 
-      for instance_name in instancelist:
-        inst = self.cfg.GetInstanceInfo(instance_name)
+      for inst in inst_data.values():
         if inst.primary_node in node_to_primary:
           node_to_primary[inst.primary_node].add(inst.name)
         for secnode in inst.secondary_nodes:
@@ -2624,7 +2753,8 @@ class LUQueryNodeStorage(NoHooksLU):
     storage_type = self.op.storage_type
 
     if storage_type not in constants.VALID_STORAGE_TYPES:
-      raise errors.OpPrereqError("Unknown storage type: %s" % storage_type)
+      raise errors.OpPrereqError("Unknown storage type: %s" % storage_type,
+                                 errors.ECODE_INVAL)
 
     _CheckOutputFields(static=self._FIELDS_STATIC,
                        dynamic=utils.FieldSet(*constants.VALID_STORAGE_FIELDS),
@@ -2718,13 +2848,15 @@ class LUModifyNodeStorage(NoHooksLU):
   def CheckArguments(self):
     node_name = self.cfg.ExpandNodeName(self.op.node_name)
     if node_name is None:
-      raise errors.OpPrereqError("Invalid node name '%s'" % self.op.node_name)
+      raise errors.OpPrereqError("Invalid node name '%s'" % self.op.node_name,
+                                 errors.ECODE_NOENT)
 
     self.op.node_name = node_name
 
     storage_type = self.op.storage_type
     if storage_type not in constants.VALID_STORAGE_TYPES:
-      raise errors.OpPrereqError("Unknown storage type: %s" % storage_type)
+      raise errors.OpPrereqError("Unknown storage type: %s" % storage_type,
+                                 errors.ECODE_INVAL)
 
   def ExpandNames(self):
     self.needed_locks = {
@@ -2741,13 +2873,15 @@ class LUModifyNodeStorage(NoHooksLU):
       modifiable = constants.MODIFIABLE_STORAGE_FIELDS[storage_type]
     except KeyError:
       raise errors.OpPrereqError("Storage units of type '%s' can not be"
-                                 " modified" % storage_type)
+                                 " modified" % storage_type,
+                                 errors.ECODE_INVAL)
 
     diff = set(self.op.changes.keys()) - modifiable
     if diff:
       raise errors.OpPrereqError("The following fields can not be modified for"
                                  " storage units of type '%s': %r" %
-                                 (storage_type, list(diff)))
+                                 (storage_type, list(diff)),
+                                 errors.ECODE_INVAL)
 
   def Exec(self, feedback_fn):
     """Computes the list of nodes and their attributes.
@@ -2799,7 +2933,7 @@ class LUAddNode(LogicalUnit):
     node_name = self.op.node_name
     cfg = self.cfg
 
-    dns_data = utils.HostInfo(node_name)
+    dns_data = utils.GetHostInfo(node_name)
 
     node = dns_data.name
     primary_ip = self.op.primary_ip = dns_data.ip
@@ -2807,15 +2941,17 @@ class LUAddNode(LogicalUnit):
     if secondary_ip is None:
       secondary_ip = primary_ip
     if not utils.IsValidIP(secondary_ip):
-      raise errors.OpPrereqError("Invalid secondary IP given")
+      raise errors.OpPrereqError("Invalid secondary IP given",
+                                 errors.ECODE_INVAL)
     self.op.secondary_ip = secondary_ip
 
     node_list = cfg.GetNodeList()
     if not self.op.readd and node in node_list:
       raise errors.OpPrereqError("Node %s is already in the configuration" %
-                                 node)
+                                 node, errors.ECODE_EXISTS)
     elif self.op.readd and node not in node_list:
-      raise errors.OpPrereqError("Node %s is not in the configuration" % node)
+      raise errors.OpPrereqError("Node %s is not in the configuration" % node,
+                                 errors.ECODE_NOENT)
 
     for existing_node_name in node_list:
       existing_node = cfg.GetNodeInfo(existing_node_name)
@@ -2824,7 +2960,8 @@ class LUAddNode(LogicalUnit):
         if (existing_node.primary_ip != primary_ip or
             existing_node.secondary_ip != secondary_ip):
           raise errors.OpPrereqError("Readded node doesn't have the same IP"
-                                     " address configuration as before")
+                                     " address configuration as before",
+                                     errors.ECODE_INVAL)
         continue
 
       if (existing_node.primary_ip == primary_ip or
@@ -2832,7 +2969,8 @@ class LUAddNode(LogicalUnit):
           existing_node.primary_ip == secondary_ip or
           existing_node.secondary_ip == secondary_ip):
         raise errors.OpPrereqError("New node ip address(es) conflict with"
-                                   " existing node %s" % existing_node.name)
+                                   " existing node %s" % existing_node.name,
+                                   errors.ECODE_NOTUNIQUE)
 
     # check that the type of the node (single versus dual homed) is the
     # same as for the master
@@ -2842,21 +2980,25 @@ class LUAddNode(LogicalUnit):
     if master_singlehomed != newbie_singlehomed:
       if master_singlehomed:
         raise errors.OpPrereqError("The master has no private ip but the"
-                                   " new node has one")
+                                   " new node has one",
+                                   errors.ECODE_INVAL)
       else:
         raise errors.OpPrereqError("The master has a private ip but the"
-                                   " new node doesn't have one")
+                                   " new node doesn't have one",
+                                   errors.ECODE_INVAL)
 
     # checks reachability
     if not utils.TcpPing(primary_ip, constants.DEFAULT_NODED_PORT):
-      raise errors.OpPrereqError("Node not reachable by ping")
+      raise errors.OpPrereqError("Node not reachable by ping",
+                                 errors.ECODE_ENVIRON)
 
     if not newbie_singlehomed:
       # check reachability from my secondary ip to newbie's secondary ip
       if not utils.TcpPing(secondary_ip, constants.DEFAULT_NODED_PORT,
                            source=myself.secondary_ip):
         raise errors.OpPrereqError("Node secondary ip not reachable by TCP"
-                                   " based ping to noded port")
+                                   " based ping to noded port",
+                                   errors.ECODE_ENVIRON)
 
     if self.op.readd:
       exceptions = [node]
@@ -2887,7 +3029,7 @@ class LUAddNode(LogicalUnit):
     # later in the procedure; this also means that if the re-add
     # fails, we are left with a non-offlined, broken node
     if self.op.readd:
-      new_node.drained = new_node.offline = False
+      new_node.drained = new_node.offline = False # pylint: disable-msg=W0201
       self.LogInfo("Readding a node, the offline/drained flags were reset")
       # if we demote the node, we do cleanup later in the procedure
       new_node.master_candidate = self.master_candidate
@@ -2932,7 +3074,7 @@ class LUAddNode(LogicalUnit):
       result = self.rpc.call_node_has_ip_address(new_node.name,
                                                  new_node.secondary_ip)
       result.Raise("Failure checking secondary ip on node %s" % new_node.name,
-                   prereq=True)
+                   prereq=True, ecode=errors.ECODE_ENVIRON)
       if not result.payload:
         raise errors.OpExecError("Node claims it doesn't have the secondary ip"
                                  " you gave (%s). Please fix and re-run this"
@@ -2970,7 +3112,7 @@ class LUAddNode(LogicalUnit):
                           " candidate status: %s" % msg)
     else:
       _RedistributeAncillaryFiles(self, additional_nodes=[node])
-      self.context.AddNode(new_node)
+      self.context.AddNode(new_node, self.proc.GetECId())
 
 
 class LUSetNodeParams(LogicalUnit):
@@ -2985,17 +3127,20 @@ class LUSetNodeParams(LogicalUnit):
   def CheckArguments(self):
     node_name = self.cfg.ExpandNodeName(self.op.node_name)
     if node_name is None:
-      raise errors.OpPrereqError("Invalid node name '%s'" % self.op.node_name)
+      raise errors.OpPrereqError("Invalid node name '%s'" % self.op.node_name,
+                                 errors.ECODE_INVAL)
     self.op.node_name = node_name
     _CheckBooleanOpField(self.op, 'master_candidate')
     _CheckBooleanOpField(self.op, 'offline')
     _CheckBooleanOpField(self.op, 'drained')
     all_mods = [self.op.offline, self.op.master_candidate, self.op.drained]
     if all_mods.count(None) == 3:
-      raise errors.OpPrereqError("Please pass at least one modification")
+      raise errors.OpPrereqError("Please pass at least one modification",
+                                 errors.ECODE_INVAL)
     if all_mods.count(True) > 1:
       raise errors.OpPrereqError("Can't set the node into more than one"
-                                 " state at the same time")
+                                 " state at the same time",
+                                 errors.ECODE_INVAL)
 
   def ExpandNames(self):
     self.needed_locks = {locking.LEVEL_NODE: self.op.node_name}
@@ -3030,7 +3175,8 @@ class LUSetNodeParams(LogicalUnit):
       # we can't change the master's node flags
       if self.op.node_name == self.cfg.GetMasterNode():
         raise errors.OpPrereqError("The master role can be changed"
-                                   " only via masterfailover")
+                                   " only via masterfailover",
+                                   errors.ECODE_INVAL)
 
     # Boolean value that tells us whether we're offlining or draining the node
     offline_or_drain = self.op.offline == True or self.op.drained == True
@@ -3050,17 +3196,18 @@ class LUSetNodeParams(LogicalUnit):
         if self.op.force and offline_or_drain and mc_should == mc_max:
           self.LogWarning(msg)
         else:
-          raise errors.OpPrereqError(msg)
+          raise errors.OpPrereqError(msg, errors.ECODE_INVAL)
 
     if (self.op.master_candidate == True and
         ((node.offline and not self.op.offline == False) or
          (node.drained and not self.op.drained == False))):
       raise errors.OpPrereqError("Node '%s' is offline or drained, can't set"
-                                 " to master_candidate" % node.name)
+                                 " to master_candidate" % node.name,
+                                 errors.ECODE_INVAL)
 
     # If we're being deofflined/drained, we'll MC ourself if needed
     if (deoffline_or_drain and not offline_or_drain and not
-        self.op.master_candidate == True):
+        self.op.master_candidate == True and not node.master_candidate):
       self.op.master_candidate = _DecideSelfPromotion(self)
       if self.op.master_candidate:
         self.LogInfo("Autopromoting node to master candidate")
@@ -3133,11 +3280,13 @@ class LUPowercycleNode(NoHooksLU):
   def CheckArguments(self):
     node_name = self.cfg.ExpandNodeName(self.op.node_name)
     if node_name is None:
-      raise errors.OpPrereqError("Invalid node name '%s'" % self.op.node_name)
+      raise errors.OpPrereqError("Invalid node name '%s'" % self.op.node_name,
+                                 errors.ECODE_NOENT)
     self.op.node_name = node_name
     if node_name == self.cfg.GetMasterNode() and not self.op.force:
       raise errors.OpPrereqError("The node is the master and the force"
-                                 " parameter was not set")
+                                 " parameter was not set",
+                                 errors.ECODE_INVAL)
 
   def ExpandNames(self):
     """Locking for PowercycleNode.
@@ -3497,15 +3646,18 @@ def _CheckNodeFreeMemory(lu, node, reason, requested, hypervisor_name):
 
   """
   nodeinfo = lu.rpc.call_node_info([node], lu.cfg.GetVGName(), hypervisor_name)
-  nodeinfo[node].Raise("Can't get data from node %s" % node, prereq=True)
+  nodeinfo[node].Raise("Can't get data from node %s" % node,
+                       prereq=True, ecode=errors.ECODE_ENVIRON)
   free_mem = nodeinfo[node].payload.get('memory_free', None)
   if not isinstance(free_mem, int):
     raise errors.OpPrereqError("Can't compute free memory on node %s, result"
-                               " was '%s'" % (node, free_mem))
+                               " was '%s'" % (node, free_mem),
+                               errors.ECODE_ENVIRON)
   if requested > free_mem:
     raise errors.OpPrereqError("Not enough memory on node %s for %s:"
                                " needed %s MiB, available %s MiB" %
-                               (node, reason, requested, free_mem))
+                               (node, reason, requested, free_mem),
+                               errors.ECODE_NORES)
 
 
 class LUStartupInstance(LogicalUnit):
@@ -3548,7 +3700,8 @@ class LUStartupInstance(LogicalUnit):
     if self.beparams:
       if not isinstance(self.beparams, dict):
         raise errors.OpPrereqError("Invalid beparams passed: %s, expected"
-                                   " dict" % (type(self.beparams), ))
+                                   " dict" % (type(self.beparams), ),
+                                   errors.ECODE_INVAL)
       # fill the beparams dict
       utils.ForceDictType(self.beparams, constants.BES_PARAMETER_TYPES)
       self.op.beparams = self.beparams
@@ -3558,7 +3711,8 @@ class LUStartupInstance(LogicalUnit):
     if self.hvparams:
       if not isinstance(self.hvparams, dict):
         raise errors.OpPrereqError("Invalid hvparams passed: %s, expected"
-                                   " dict" % (type(self.hvparams), ))
+                                   " dict" % (type(self.hvparams), ),
+                                   errors.ECODE_INVAL)
 
       # check hypervisor parameter syntax (locally)
       cluster = self.cfg.GetClusterInfo()
@@ -3581,7 +3735,7 @@ class LUStartupInstance(LogicalUnit):
                                               instance.name,
                                               instance.hypervisor)
     remote_info.Raise("Error checking node %s" % instance.primary_node,
-                      prereq=True)
+                      prereq=True, ecode=errors.ECODE_ENVIRON)
     if not remote_info.payload: # not running already
       _CheckNodeFreeMemory(self, instance.primary_node,
                            "starting instance %s" % instance.name,
@@ -3790,19 +3944,22 @@ class LUReinstallInstance(LogicalUnit):
 
     if instance.disk_template == constants.DT_DISKLESS:
       raise errors.OpPrereqError("Instance '%s' has no disks" %
-                                 self.op.instance_name)
+                                 self.op.instance_name,
+                                 errors.ECODE_INVAL)
     if instance.admin_up:
       raise errors.OpPrereqError("Instance '%s' is marked to be up" %
-                                 self.op.instance_name)
+                                 self.op.instance_name,
+                                 errors.ECODE_STATE)
     remote_info = self.rpc.call_instance_info(instance.primary_node,
                                               instance.name,
                                               instance.hypervisor)
     remote_info.Raise("Error checking node %s" % instance.primary_node,
-                      prereq=True)
+                      prereq=True, ecode=errors.ECODE_ENVIRON)
     if remote_info.payload:
       raise errors.OpPrereqError("Instance '%s' is running on the node %s" %
                                  (self.op.instance_name,
-                                  instance.primary_node))
+                                  instance.primary_node),
+                                 errors.ECODE_STATE)
 
     self.op.os_type = getattr(self.op, "os_type", None)
     self.op.force_variant = getattr(self.op, "force_variant", False)
@@ -3812,10 +3969,11 @@ class LUReinstallInstance(LogicalUnit):
         self.cfg.ExpandNodeName(instance.primary_node))
       if pnode is None:
         raise errors.OpPrereqError("Primary node '%s' is unknown" %
-                                   self.op.pnode)
+                                   self.op.pnode, errors.ECODE_NOENT)
       result = self.rpc.call_os_get(pnode.name, self.op.os_type)
       result.Raise("OS '%s' not in supported OS list for primary node %s" %
-                   (self.op.os_type, pnode.name), prereq=True)
+                   (self.op.os_type, pnode.name),
+                   prereq=True, ecode=errors.ECODE_INVAL)
       if not self.op.force_variant:
         _CheckOSVariant(result.payload, self.op.os_type)
 
@@ -3835,7 +3993,8 @@ class LUReinstallInstance(LogicalUnit):
     _StartInstanceDisks(self, inst, None)
     try:
       feedback_fn("Running the instance OS create scripts...")
-      result = self.rpc.call_instance_os_add(inst.primary_node, inst, True)
+      # FIXME: pass debug option from opcode to backend
+      result = self.rpc.call_instance_os_add(inst.primary_node, inst, True, 0)
       result.Raise("Could not install OS for instance %s on node %s" %
                    (inst.name, inst.primary_node))
     finally:
@@ -3856,12 +4015,12 @@ class LURecreateInstanceDisks(LogicalUnit):
 
     """
     if not isinstance(self.op.disks, list):
-      raise errors.OpPrereqError("Invalid disks parameter")
+      raise errors.OpPrereqError("Invalid disks parameter", errors.ECODE_INVAL)
     for item in self.op.disks:
       if (not isinstance(item, int) or
           item < 0):
         raise errors.OpPrereqError("Invalid disk specification '%s'" %
-                                   str(item))
+                                   str(item), errors.ECODE_INVAL)
 
   def ExpandNames(self):
     self._ExpandAndLockInstance()
@@ -3889,26 +4048,27 @@ class LURecreateInstanceDisks(LogicalUnit):
 
     if instance.disk_template == constants.DT_DISKLESS:
       raise errors.OpPrereqError("Instance '%s' has no disks" %
-                                 self.op.instance_name)
+                                 self.op.instance_name, errors.ECODE_INVAL)
     if instance.admin_up:
       raise errors.OpPrereqError("Instance '%s' is marked to be up" %
-                                 self.op.instance_name)
+                                 self.op.instance_name, errors.ECODE_STATE)
     remote_info = self.rpc.call_instance_info(instance.primary_node,
                                               instance.name,
                                               instance.hypervisor)
     remote_info.Raise("Error checking node %s" % instance.primary_node,
-                      prereq=True)
+                      prereq=True, ecode=errors.ECODE_ENVIRON)
     if remote_info.payload:
       raise errors.OpPrereqError("Instance '%s' is running on the node %s" %
                                  (self.op.instance_name,
-                                  instance.primary_node))
+                                  instance.primary_node), errors.ECODE_STATE)
 
     if not self.op.disks:
       self.op.disks = range(len(instance.disks))
     else:
       for idx in self.op.disks:
         if idx >= len(instance.disks):
-          raise errors.OpPrereqError("Invalid disk index passed '%s'" % idx)
+          raise errors.OpPrereqError("Invalid disk index passed '%s'" % idx,
+                                     errors.ECODE_INVAL)
 
     self.instance = instance
 
@@ -3917,7 +4077,7 @@ class LURecreateInstanceDisks(LogicalUnit):
 
     """
     to_skip = []
-    for idx, disk in enumerate(self.instance.disks):
+    for idx, _ in enumerate(self.instance.disks):
       if idx not in self.op.disks: # disk idx has not been passed in
         to_skip.append(idx)
         continue
@@ -3954,36 +4114,37 @@ class LURenameInstance(LogicalUnit):
       self.cfg.ExpandInstanceName(self.op.instance_name))
     if instance is None:
       raise errors.OpPrereqError("Instance '%s' not known" %
-                                 self.op.instance_name)
+                                 self.op.instance_name, errors.ECODE_NOENT)
     _CheckNodeOnline(self, instance.primary_node)
 
     if instance.admin_up:
       raise errors.OpPrereqError("Instance '%s' is marked to be up" %
-                                 self.op.instance_name)
+                                 self.op.instance_name, errors.ECODE_STATE)
     remote_info = self.rpc.call_instance_info(instance.primary_node,
                                               instance.name,
                                               instance.hypervisor)
     remote_info.Raise("Error checking node %s" % instance.primary_node,
-                      prereq=True)
+                      prereq=True, ecode=errors.ECODE_ENVIRON)
     if remote_info.payload:
       raise errors.OpPrereqError("Instance '%s' is running on the node %s" %
                                  (self.op.instance_name,
-                                  instance.primary_node))
+                                  instance.primary_node), errors.ECODE_STATE)
     self.instance = instance
 
     # new name verification
-    name_info = utils.HostInfo(self.op.new_name)
+    name_info = utils.GetHostInfo(self.op.new_name)
 
     self.op.new_name = new_name = name_info.name
     instance_list = self.cfg.GetInstanceList()
     if new_name in instance_list:
       raise errors.OpPrereqError("Instance '%s' is already in the cluster" %
-                                 new_name)
+                                 new_name, errors.ECODE_EXISTS)
 
     if not getattr(self.op, "ignore_ip", False):
       if utils.TcpPing(name_info.ip, constants.DEFAULT_NODED_PORT):
         raise errors.OpPrereqError("IP %s of instance %s already in use" %
-                                   (name_info.ip, new_name))
+                                   (name_info.ip, new_name),
+                                   errors.ECODE_NOTUNIQUE)
 
 
   def Exec(self, feedback_fn):
@@ -4017,7 +4178,7 @@ class LURenameInstance(LogicalUnit):
     _StartInstanceDisks(self, inst, None)
     try:
       result = self.rpc.call_instance_run_rename(inst.primary_node, inst,
-                                                 old_name)
+                                                 old_name, 0)
       msg = result.fail_msg
       if msg:
         msg = ("Could not run OS rename script for instance %s on node %s"
@@ -4111,6 +4272,7 @@ class LUQueryInstances(NoHooksLU):
   """Logical unit for querying instances.
 
   """
+  # pylint: disable-msg=W0142
   _OP_REQP = ["output_fields", "names", "use_locking"]
   REQ_BGL = False
   _SIMPLE_FIELDS = ["name", "os", "network_port", "hypervisor",
@@ -4130,7 +4292,8 @@ class LUQueryInstances(NoHooksLU):
                                     "hvparams",
                                     ] + _SIMPLE_FIELDS +
                                   ["hv/%s" % name
-                                   for name in constants.HVS_PARAMETERS] +
+                                   for name in constants.HVS_PARAMETERS
+                                   if name not in constants.HVC_GLOBALS] +
                                   ["be/%s" % name
                                    for name in constants.BES_PARAMETERS])
   _FIELDS_DYNAMIC = utils.FieldSet("oper_state", "oper_ram", "status")
@@ -4171,6 +4334,8 @@ class LUQueryInstances(NoHooksLU):
     """Computes the list of nodes and their attributes.
 
     """
+    # pylint: disable-msg=R0912
+    # way too many branches here
     all_info = self.cfg.GetAllInstancesInfo()
     if self.wanted == locking.ALL_SET:
       # caller didn't specify instance names, so ordering is not important
@@ -4225,7 +4390,7 @@ class LUQueryInstances(NoHooksLU):
     cluster = self.cfg.GetClusterInfo()
     for instance in instance_list:
       iout = []
-      i_hv = cluster.FillHV(instance)
+      i_hv = cluster.FillHV(instance, skip_globals=True)
       i_be = cluster.FillBE(instance)
       i_nicp = [objects.FillDict(cluster.nicparams[constants.PP_DEFAULT],
                                  nic.nicparams) for nic in instance.nics]
@@ -4312,7 +4477,8 @@ class LUQueryInstances(NoHooksLU):
         elif field == "hvparams":
           val = i_hv
         elif (field.startswith(HVPREFIX) and
-              field[len(HVPREFIX):] in constants.HVS_PARAMETERS):
+              field[len(HVPREFIX):] in constants.HVS_PARAMETERS and
+              field[len(HVPREFIX):] not in constants.HVC_GLOBALS):
           val = i_hv.get(field[len(HVPREFIX):], None)
         elif field == "beparams":
           val = i_be
@@ -4437,7 +4603,8 @@ class LUFailoverInstance(LogicalUnit):
     bep = self.cfg.GetClusterInfo().FillBE(instance)
     if instance.disk_template not in constants.DTS_NET_MIRROR:
       raise errors.OpPrereqError("Instance's disk layout is not"
-                                 " network mirrored, cannot failover.")
+                                 " network mirrored, cannot failover.",
+                                 errors.ECODE_STATE)
 
     secondary_nodes = instance.secondary_nodes
     if not secondary_nodes:
@@ -4591,7 +4758,7 @@ class LUMoveInstance(LogicalUnit):
     target_node = self.cfg.ExpandNodeName(self.op.target_node)
     if target_node is None:
       raise errors.OpPrereqError("Node '%s' not known" %
-                                  self.op.target_node)
+                                  self.op.target_node, errors.ECODE_NOENT)
     self.op.target_node = target_node
     self.needed_locks[locking.LEVEL_NODE] = [target_node]
     self.recalculate_locks[locking.LEVEL_NODE] = constants.LOCKS_APPEND
@@ -4633,14 +4800,15 @@ class LUMoveInstance(LogicalUnit):
 
     if target_node == instance.primary_node:
       raise errors.OpPrereqError("Instance %s is already on the node %s" %
-                                 (instance.name, target_node))
+                                 (instance.name, target_node),
+                                 errors.ECODE_STATE)
 
     bep = self.cfg.GetClusterInfo().FillBE(instance)
 
     for idx, dsk in enumerate(instance.disks):
       if dsk.dev_type not in (constants.LD_LV, constants.LD_FILE):
         raise errors.OpPrereqError("Instance disk %d has a complex layout,"
-                                   " cannot copy")
+                                   " cannot copy" % idx, errors.ECODE_STATE)
 
     _CheckNodeOnline(self, target_node)
     _CheckNodeNotDrained(self, target_node)
@@ -4766,7 +4934,8 @@ class LUMigrateNode(LogicalUnit):
   def ExpandNames(self):
     self.op.node_name = self.cfg.ExpandNodeName(self.op.node_name)
     if self.op.node_name is None:
-      raise errors.OpPrereqError("Node '%s' not known" % self.op.node_name)
+      raise errors.OpPrereqError("Node '%s' not known" % self.op.node_name,
+                                 errors.ECODE_NOENT)
 
     self.needed_locks = {
       locking.LEVEL_NODE: [self.op.node_name],
@@ -4830,11 +4999,11 @@ class TLMigrateInstance(Tasklet):
       self.cfg.ExpandInstanceName(self.instance_name))
     if instance is None:
       raise errors.OpPrereqError("Instance '%s' not known" %
-                                 self.instance_name)
+                                 self.instance_name, errors.ECODE_NOENT)
 
     if instance.disk_template != constants.DT_DRBD8:
       raise errors.OpPrereqError("Instance's disk layout is not"
-                                 " drbd8, cannot migrate.")
+                                 " drbd8, cannot migrate.", errors.ECODE_STATE)
 
     secondary_nodes = instance.secondary_nodes
     if not secondary_nodes:
@@ -4856,7 +5025,8 @@ class TLMigrateInstance(Tasklet):
       _CheckNodeNotDrained(self, target_node)
       result = self.rpc.call_instance_migratable(instance.primary_node,
                                                  instance)
-      result.Raise("Can't migrate, please use failover", prereq=True)
+      result.Raise("Can't migrate, please use failover",
+                   prereq=True, ecode=errors.ECODE_STATE)
 
     self.instance = instance
 
@@ -5018,8 +5188,8 @@ class TLMigrateInstance(Tasklet):
                                                     False)
     abort_msg = abort_result.fail_msg
     if abort_msg:
-      logging.error("Aborting migration failed on target node %s: %s" %
-                    (target_node, abort_msg))
+      logging.error("Aborting migration failed on target node %s: %s",
+                    target_node, abort_msg)
       # Don't raise an exception here, as we stil have to try to revert the
       # disk status, even if this step failed.
 
@@ -5073,6 +5243,7 @@ class TLMigrateInstance(Tasklet):
     if msg:
       logging.error("Instance pre-migration failed, trying to revert"
                     " disk status: %s", msg)
+      self.feedback_fn("Pre-migration failed, aborting")
       self._AbortMigration()
       self._RevertDiskStatus()
       raise errors.OpExecError("Could not pre-migrate instance %s: %s" %
@@ -5087,6 +5258,7 @@ class TLMigrateInstance(Tasklet):
     if msg:
       logging.error("Instance migration failed, trying to revert"
                     " disk status: %s", msg)
+      self.feedback_fn("Migration failed, aborting")
       self._AbortMigration()
       self._RevertDiskStatus()
       raise errors.OpExecError("Could not migrate instance %s: %s" %
@@ -5104,7 +5276,7 @@ class TLMigrateInstance(Tasklet):
     msg = result.fail_msg
     if msg:
       logging.error("Instance migration succeeded, but finalization failed:"
-                    " %s" % msg)
+                    " %s", msg)
       raise errors.OpExecError("Could not finalize instance migration: %s" %
                                msg)
 
@@ -5218,7 +5390,7 @@ def _GenerateUniqueNames(lu, exts):
   """
   results = []
   for val in exts:
-    new_id = lu.cfg.GenerateUniqueID()
+    new_id = lu.cfg.GenerateUniqueID(lu.proc.GetECId())
     results.append("%s%s" % (new_id, val))
   return results
 
@@ -5230,7 +5402,7 @@ def _GenerateDRBD8Branch(lu, primary, secondary, size, names, iv_name,
   """
   port = lu.cfg.AllocatePort()
   vgname = lu.cfg.GetVGName()
-  shared_secret = lu.cfg.GenerateDRBDSecret()
+  shared_secret = lu.cfg.GenerateDRBDSecret(lu.proc.GetECId())
   dev_data = objects.Disk(dev_type=constants.LD_LV, size=size,
                           logical_id=(vgname, names[0]))
   dev_meta = objects.Disk(dev_type=constants.LD_LV, size=128,
@@ -5470,13 +5642,26 @@ class LUCreateInstance(LogicalUnit):
               "hvparams", "beparams"]
   REQ_BGL = False
 
+  def CheckArguments(self):
+    """Check arguments.
+
+    """
+    # do not require name_check to ease forward/backward compatibility
+    # for tools
+    if not hasattr(self.op, "name_check"):
+      self.op.name_check = True
+    if self.op.ip_check and not self.op.name_check:
+      # TODO: make the ip check more flexible and not depend on the name check
+      raise errors.OpPrereqError("Cannot do ip checks without a name check",
+                                 errors.ECODE_INVAL)
+
   def _ExpandNode(self, node):
     """Expands and checks one node name.
 
     """
     node_full = self.cfg.ExpandNodeName(node)
     if node_full is None:
-      raise errors.OpPrereqError("Unknown node %s" % node)
+      raise errors.OpPrereqError("Unknown node %s" % node, errors.ECODE_NOENT)
     return node_full
 
   def ExpandNames(self):
@@ -5498,11 +5683,12 @@ class LUCreateInstance(LogicalUnit):
     if self.op.mode not in (constants.INSTANCE_CREATE,
                             constants.INSTANCE_IMPORT):
       raise errors.OpPrereqError("Invalid instance creation mode '%s'" %
-                                 self.op.mode)
+                                 self.op.mode, errors.ECODE_INVAL)
 
     # disk template and mirror node verification
     if self.op.disk_template not in constants.DISK_TEMPLATES:
-      raise errors.OpPrereqError("Invalid disk template name")
+      raise errors.OpPrereqError("Invalid disk template name",
+                                 errors.ECODE_INVAL)
 
     if self.op.hypervisor is None:
       self.op.hypervisor = self.cfg.GetHypervisorType()
@@ -5512,7 +5698,8 @@ class LUCreateInstance(LogicalUnit):
     if self.op.hypervisor not in enabled_hvs:
       raise errors.OpPrereqError("Selected hypervisor (%s) not enabled in the"
                                  " cluster (%s)" % (self.op.hypervisor,
-                                  ",".join(enabled_hvs)))
+                                  ",".join(enabled_hvs)),
+                                 errors.ECODE_STATE)
 
     # check hypervisor parameter syntax (locally)
     utils.ForceDictType(self.op.hvparams, constants.HVS_PARAMETER_TYPES)
@@ -5521,6 +5708,8 @@ class LUCreateInstance(LogicalUnit):
     hv_type = hypervisor.GetHypervisor(self.op.hypervisor)
     hv_type.CheckParameterSyntax(filled_hvp)
     self.hv_full = filled_hvp
+    # check that we don't specify global parameters on an instance
+    _CheckGlobalHvParams(self.op.hvparams)
 
     # fill and remember the beparams dict
     utils.ForceDictType(self.op.beparams, constants.BES_PARAMETER_TYPES)
@@ -5530,14 +5719,20 @@ class LUCreateInstance(LogicalUnit):
     #### instance parameters check
 
     # instance name verification
-    hostname1 = utils.HostInfo(self.op.instance_name)
-    self.op.instance_name = instance_name = hostname1.name
+    if self.op.name_check:
+      hostname1 = utils.GetHostInfo(self.op.instance_name)
+      self.op.instance_name = instance_name = hostname1.name
+      # used in CheckPrereq for ip ping check
+      self.check_ip = hostname1.ip
+    else:
+      instance_name = self.op.instance_name
+      self.check_ip = None
 
     # this is just a preventive check, but someone might still add this
     # instance in the meantime, and creation will fail at lock-add time
     if instance_name in self.cfg.GetInstanceList():
       raise errors.OpPrereqError("Instance '%s' is already in the cluster" %
-                                 instance_name)
+                                 instance_name, errors.ECODE_EXISTS)
 
     self.add_locks[locking.LEVEL_INSTANCE] = instance_name
 
@@ -5560,37 +5755,44 @@ class LUCreateInstance(LogicalUnit):
       if ip is None or ip.lower() == constants.VALUE_NONE:
         nic_ip = None
       elif ip.lower() == constants.VALUE_AUTO:
+        if not self.op.name_check:
+          raise errors.OpPrereqError("IP address set to auto but name checks"
+                                     " have been skipped. Aborting.",
+                                     errors.ECODE_INVAL)
         nic_ip = hostname1.ip
       else:
         if not utils.IsValidIP(ip):
           raise errors.OpPrereqError("Given IP address '%s' doesn't look"
-                                     " like a valid IP" % ip)
+                                     " like a valid IP" % ip,
+                                     errors.ECODE_INVAL)
         nic_ip = ip
 
-      # TODO: check the ip for uniqueness !!
+      # TODO: check the ip address for uniqueness
       if nic_mode == constants.NIC_MODE_ROUTED and not nic_ip:
-        raise errors.OpPrereqError("Routed nic mode requires an ip address")
+        raise errors.OpPrereqError("Routed nic mode requires an ip address",
+                                   errors.ECODE_INVAL)
 
       # MAC address verification
       mac = nic.get("mac", constants.VALUE_AUTO)
       if mac not in (constants.VALUE_AUTO, constants.VALUE_GENERATE):
-        if not utils.IsValidMac(mac.lower()):
-          raise errors.OpPrereqError("Invalid MAC address specified: %s" %
-                                     mac)
-        else:
-          # or validate/reserve the current one
-          if self.cfg.IsMacInUse(mac):
-            raise errors.OpPrereqError("MAC address %s already in use"
-                                       " in cluster" % mac)
+        mac = utils.NormalizeAndValidateMac(mac)
+
+        try:
+          self.cfg.ReserveMAC(mac, self.proc.GetECId())
+        except errors.ReservationError:
+          raise errors.OpPrereqError("MAC address %s already in use"
+                                     " in cluster" % mac,
+                                     errors.ECODE_NOTUNIQUE)
 
       # bridge verification
       bridge = nic.get("bridge", None)
       link = nic.get("link", None)
       if bridge and link:
         raise errors.OpPrereqError("Cannot pass 'bridge' and 'link'"
-                                   " at the same time")
+                                   " at the same time", errors.ECODE_INVAL)
       elif bridge and nic_mode == constants.NIC_MODE_ROUTED:
-        raise errors.OpPrereqError("Cannot pass 'bridge' on a routed nic")
+        raise errors.OpPrereqError("Cannot pass 'bridge' on a routed nic",
+                                   errors.ECODE_INVAL)
       elif bridge:
         link = bridge
 
@@ -5611,32 +5813,32 @@ class LUCreateInstance(LogicalUnit):
       mode = disk.get("mode", constants.DISK_RDWR)
       if mode not in constants.DISK_ACCESS_SET:
         raise errors.OpPrereqError("Invalid disk access mode '%s'" %
-                                   mode)
+                                   mode, errors.ECODE_INVAL)
       size = disk.get("size", None)
       if size is None:
-        raise errors.OpPrereqError("Missing disk size")
+        raise errors.OpPrereqError("Missing disk size", errors.ECODE_INVAL)
       try:
         size = int(size)
-      except ValueError:
-        raise errors.OpPrereqError("Invalid disk size '%s'" % size)
+      except (TypeError, ValueError):
+        raise errors.OpPrereqError("Invalid disk size '%s'" % size,
+                                   errors.ECODE_INVAL)
       self.disks.append({"size": size, "mode": mode})
 
-    # used in CheckPrereq for ip ping check
-    self.check_ip = hostname1.ip
-
     # file storage checks
     if (self.op.file_driver and
         not self.op.file_driver in constants.FILE_DRIVER):
       raise errors.OpPrereqError("Invalid file driver name '%s'" %
-                                 self.op.file_driver)
+                                 self.op.file_driver, errors.ECODE_INVAL)
 
     if self.op.file_storage_dir and os.path.isabs(self.op.file_storage_dir):
-      raise errors.OpPrereqError("File storage directory path not absolute")
+      raise errors.OpPrereqError("File storage directory path not absolute",
+                                 errors.ECODE_INVAL)
 
     ### Node/iallocator related checks
     if [self.op.iallocator, self.op.pnode].count(None) != 1:
       raise errors.OpPrereqError("One and only one of iallocator and primary"
-                                 " node must be given")
+                                 " node must be given",
+                                 errors.ECODE_INVAL)
 
     if self.op.iallocator:
       self.needed_locks[locking.LEVEL_NODE] = locking.ALL_SET
@@ -5661,7 +5863,8 @@ class LUCreateInstance(LogicalUnit):
         self.op.src_node = None
         if os.path.isabs(src_path):
           raise errors.OpPrereqError("Importing an instance from an absolute"
-                                     " path requires a source node option.")
+                                     " path requires a source node option.",
+                                     errors.ECODE_INVAL)
       else:
         self.op.src_node = src_node = self._ExpandNode(src_node)
         if self.needed_locks[locking.LEVEL_NODE] is not locking.ALL_SET:
@@ -5677,7 +5880,8 @@ class LUCreateInstance(LogicalUnit):
 
     else: # INSTANCE_CREATE
       if getattr(self.op, "os_type", None) is None:
-        raise errors.OpPrereqError("No guest OS specified")
+        raise errors.OpPrereqError("No guest OS specified",
+                                   errors.ECODE_INVAL)
       self.op.force_variant = getattr(self.op, "force_variant", False)
 
   def _RunAllocator(self):
@@ -5702,17 +5906,18 @@ class LUCreateInstance(LogicalUnit):
 
     if not ial.success:
       raise errors.OpPrereqError("Can't compute nodes using"
-                                 " iallocator '%s': %s" % (self.op.iallocator,
-                                                           ial.info))
+                                 " iallocator '%s': %s" %
+                                 (self.op.iallocator, ial.info),
+                                 errors.ECODE_NORES)
     if len(ial.nodes) != ial.required_nodes:
       raise errors.OpPrereqError("iallocator '%s' returned invalid number"
                                  " of nodes (%s), required %s" %
                                  (self.op.iallocator, len(ial.nodes),
-                                  ial.required_nodes))
+                                  ial.required_nodes), errors.ECODE_FAULT)
     self.op.pnode = ial.nodes[0]
     self.LogInfo("Selected nodes for instance %s via iallocator %s: %s",
                  self.op.instance_name, self.op.iallocator,
-                 ", ".join(ial.nodes))
+                 utils.CommaJoin(ial.nodes))
     if ial.required_nodes == 2:
       self.op.snode = ial.nodes[1]
 
@@ -5758,7 +5963,7 @@ class LUCreateInstance(LogicalUnit):
     if (not self.cfg.GetVGName() and
         self.op.disk_template not in constants.DTS_NOT_LVM):
       raise errors.OpPrereqError("Cluster does not support lvm-based"
-                                 " instances")
+                                 " instances", errors.ECODE_STATE)
 
     if self.op.mode == constants.INSTANCE_IMPORT:
       src_node = self.op.src_node
@@ -5779,7 +5984,7 @@ class LUCreateInstance(LogicalUnit):
             break
         if not found:
           raise errors.OpPrereqError("No export found for relative path %s" %
-                                      src_path)
+                                      src_path, errors.ECODE_INVAL)
 
       _CheckNodeOnline(self, src_node)
       result = self.rpc.call_export_info(src_node, src_path)
@@ -5787,12 +5992,14 @@ class LUCreateInstance(LogicalUnit):
 
       export_info = objects.SerializableConfigParser.Loads(str(result.payload))
       if not export_info.has_section(constants.INISECT_EXP):
-        raise errors.ProgrammerError("Corrupted export config")
+        raise errors.ProgrammerError("Corrupted export config",
+                                     errors.ECODE_ENVIRON)
 
       ei_version = export_info.get(constants.INISECT_EXP, 'version')
       if (int(ei_version) != constants.EXPORT_VERSION):
         raise errors.OpPrereqError("Wrong export version %s (wanted %d)" %
-                                   (ei_version, constants.EXPORT_VERSION))
+                                   (ei_version, constants.EXPORT_VERSION),
+                                   errors.ECODE_ENVIRON)
 
       # Check that the new instance doesn't have less disks than the export
       instance_disks = len(self.disks)
@@ -5800,7 +6007,8 @@ class LUCreateInstance(LogicalUnit):
       if instance_disks < export_disks:
         raise errors.OpPrereqError("Not enough disks to import."
                                    " (instance: %d, export: %d)" %
-                                   (instance_disks, export_disks))
+                                   (instance_disks, export_disks),
+                                   errors.ECODE_INVAL)
 
       self.op.os_type = export_info.get(constants.INISECT_EXP, 'os')
       disk_images = []
@@ -5826,15 +6034,13 @@ class LUCreateInstance(LogicalUnit):
             nic.mac = export_info.get(constants.INISECT_INS, nic_mac_ini)
 
     # ENDIF: self.op.mode == constants.INSTANCE_IMPORT
-    # ip ping checks (we use the same ip that was resolved in ExpandNames)
-    if self.op.start and not self.op.ip_check:
-      raise errors.OpPrereqError("Cannot ignore IP address conflicts when"
-                                 " adding an instance in start mode")
 
+    # ip ping checks (we use the same ip that was resolved in ExpandNames)
     if self.op.ip_check:
       if utils.TcpPing(self.check_ip, constants.DEFAULT_NODED_PORT):
         raise errors.OpPrereqError("IP %s of instance %s already in use" %
-                                   (self.check_ip, self.op.instance_name))
+                                   (self.check_ip, self.op.instance_name),
+                                   errors.ECODE_NOTUNIQUE)
 
     #### mac address generation
     # By generating here the mac address both the allocator and the hooks get
@@ -5846,7 +6052,7 @@ class LUCreateInstance(LogicalUnit):
     # creation job will fail.
     for nic in self.nics:
       if nic.mac in (constants.VALUE_AUTO, constants.VALUE_GENERATE):
-        nic.mac = self.cfg.GenerateMAC()
+        nic.mac = self.cfg.GenerateMAC(self.proc.GetECId())
 
     #### allocator run
 
@@ -5861,10 +6067,10 @@ class LUCreateInstance(LogicalUnit):
       "Cannot retrieve locked node %s" % self.op.pnode
     if pnode.offline:
       raise errors.OpPrereqError("Cannot use offline primary node '%s'" %
-                                 pnode.name)
+                                 pnode.name, errors.ECODE_STATE)
     if pnode.drained:
       raise errors.OpPrereqError("Cannot use drained primary node '%s'" %
-                                 pnode.name)
+                                 pnode.name, errors.ECODE_STATE)
 
     self.secondaries = []
 
@@ -5872,10 +6078,10 @@ class LUCreateInstance(LogicalUnit):
     if self.op.disk_template in constants.DTS_NET_MIRROR:
       if self.op.snode is None:
         raise errors.OpPrereqError("The networked disk templates need"
-                                   " a mirror node")
+                                   " a mirror node", errors.ECODE_INVAL)
       if self.op.snode == pnode.name:
-        raise errors.OpPrereqError("The secondary node cannot be"
-                                   " the primary node.")
+        raise errors.OpPrereqError("The secondary node cannot be the"
+                                   " primary node.", errors.ECODE_INVAL)
       _CheckNodeOnline(self, self.op.snode)
       _CheckNodeNotDrained(self, self.op.snode)
       self.secondaries.append(self.op.snode)
@@ -5896,18 +6102,20 @@ class LUCreateInstance(LogicalUnit):
         vg_free = info.get('vg_free', None)
         if not isinstance(vg_free, int):
           raise errors.OpPrereqError("Can't compute free disk space on"
-                                     " node %s" % node)
+                                     " node %s" % node, errors.ECODE_ENVIRON)
         if req_size > vg_free:
           raise errors.OpPrereqError("Not enough disk space on target node %s."
                                      " %d MB available, %d MB required" %
-                                     (node, vg_free, req_size))
+                                     (node, vg_free, req_size),
+                                     errors.ECODE_NORES)
 
     _CheckHVParams(self, nodenames, self.op.hypervisor, self.op.hvparams)
 
     # os verification
     result = self.rpc.call_os_get(pnode.name, self.op.os_type)
     result.Raise("OS '%s' not in supported os list for primary node %s" %
-                 (self.op.os_type, pnode.name), prereq=True)
+                 (self.op.os_type, pnode.name),
+                 prereq=True, ecode=errors.ECODE_INVAL)
     if not self.op.force_variant:
       _CheckOSVariant(result.payload, self.op.os_type)
 
@@ -5983,7 +6191,8 @@ class LUCreateInstance(LogicalUnit):
 
     feedback_fn("adding instance %s to cluster config" % instance)
 
-    self.cfg.AddInstance(iobj)
+    self.cfg.AddInstance(iobj, self.proc.GetECId())
+
     # Declare that we don't want to remove the instance lock anymore, as we've
     # added the instance to the config
     del self.remove_locks[locking.LEVEL_INSTANCE]
@@ -6022,7 +6231,8 @@ class LUCreateInstance(LogicalUnit):
     if iobj.disk_template != constants.DT_DISKLESS:
       if self.op.mode == constants.INSTANCE_CREATE:
         feedback_fn("* running the instance OS create scripts...")
-        result = self.rpc.call_instance_os_add(pnode_name, iobj, False)
+        # FIXME: pass debug option from opcode to backend
+        result = self.rpc.call_instance_os_add(pnode_name, iobj, False, 0)
         result.Raise("Could not add os for instance %s"
                      " on node %s" % (instance, pnode_name))
 
@@ -6031,9 +6241,10 @@ class LUCreateInstance(LogicalUnit):
         src_node = self.op.src_node
         src_images = self.src_images
         cluster_name = self.cfg.GetClusterName()
+        # FIXME: pass debug option from opcode to backend
         import_result = self.rpc.call_instance_os_import(pnode_name, iobj,
                                                          src_node, src_images,
-                                                         cluster_name)
+                                                         cluster_name, 0)
         msg = import_result.fail_msg
         if msg:
           self.LogWarning("Error while importing the disk images for instance"
@@ -6135,7 +6346,7 @@ class LUReplaceDisks(LogicalUnit):
       remote_node = self.cfg.ExpandNodeName(self.op.remote_node)
       if remote_node is None:
         raise errors.OpPrereqError("Node '%s' not known" %
-                                   self.op.remote_node)
+                                   self.op.remote_node, errors.ECODE_NOENT)
 
       self.op.remote_node = remote_node
 
@@ -6152,7 +6363,7 @@ class LUReplaceDisks(LogicalUnit):
 
     self.replacer = TLReplaceDisks(self, self.op.instance_name, self.op.mode,
                                    self.op.iallocator, self.op.remote_node,
-                                   self.op.disks)
+                                   self.op.disks, False)
 
     self.tasklets = [self.replacer]
 
@@ -6207,7 +6418,8 @@ class LUEvacuateNode(LogicalUnit):
   def ExpandNames(self):
     self.op.node_name = self.cfg.ExpandNodeName(self.op.node_name)
     if self.op.node_name is None:
-      raise errors.OpPrereqError("Node '%s' not known" % self.op.node_name)
+      raise errors.OpPrereqError("Node '%s' not known" % self.op.node_name,
+                                 errors.ECODE_NOENT)
 
     self.needed_locks = {}
 
@@ -6219,7 +6431,7 @@ class LUEvacuateNode(LogicalUnit):
       remote_node = self.cfg.ExpandNodeName(self.op.remote_node)
       if remote_node is None:
         raise errors.OpPrereqError("Node '%s' not known" %
-                                   self.op.remote_node)
+                                   self.op.remote_node, errors.ECODE_NOENT)
 
       self.op.remote_node = remote_node
 
@@ -6231,7 +6443,7 @@ class LUEvacuateNode(LogicalUnit):
       self.recalculate_locks[locking.LEVEL_NODE] = constants.LOCKS_APPEND
 
     else:
-      raise errors.OpPrereqError("Invalid parameters")
+      raise errors.OpPrereqError("Invalid parameters", errors.ECODE_INVAL)
 
     # Create tasklets for replacing disks for all secondary instances on this
     # node
@@ -6243,7 +6455,8 @@ class LUEvacuateNode(LogicalUnit):
       names.append(inst.name)
 
       replacer = TLReplaceDisks(self, inst.name, constants.REPLACE_DISK_CHG,
-                                self.op.iallocator, self.op.remote_node, [])
+                                self.op.iallocator, self.op.remote_node, [],
+                                True)
       tasklets.append(replacer)
 
     self.tasklets = tasklets
@@ -6285,7 +6498,7 @@ class TLReplaceDisks(Tasklet):
 
   """
   def __init__(self, lu, instance_name, mode, iallocator_name, remote_node,
-               disks):
+               disks, delay_iallocator):
     """Initializes this class.
 
     """
@@ -6297,6 +6510,7 @@ class TLReplaceDisks(Tasklet):
     self.iallocator_name = iallocator_name
     self.remote_node = remote_node
     self.disks = disks
+    self.delay_iallocator = delay_iallocator
 
     # Runtime data
     self.instance = None
@@ -6316,17 +6530,17 @@ class TLReplaceDisks(Tasklet):
       if remote_node is None and iallocator is None:
         raise errors.OpPrereqError("When changing the secondary either an"
                                    " iallocator script must be used or the"
-                                   " new node given")
+                                   " new node given", errors.ECODE_INVAL)
 
       if remote_node is not None and iallocator is not None:
         raise errors.OpPrereqError("Give either the iallocator or the new"
-                                   " secondary, not both")
+                                   " secondary, not both", errors.ECODE_INVAL)
 
     elif remote_node is not None or iallocator is not None:
       # Not replacing the secondary
       raise errors.OpPrereqError("The iallocator and new node options can"
                                  " only be used when changing the"
-                                 " secondary node")
+                                 " secondary node", errors.ECODE_INVAL)
 
   @staticmethod
   def _RunAllocator(lu, iallocator_name, instance_name, relocate_from):
@@ -6342,12 +6556,15 @@ class TLReplaceDisks(Tasklet):
 
     if not ial.success:
       raise errors.OpPrereqError("Can't compute nodes using iallocator '%s':"
-                                 " %s" % (iallocator_name, ial.info))
+                                 " %s" % (iallocator_name, ial.info),
+                                 errors.ECODE_NORES)
 
     if len(ial.nodes) != ial.required_nodes:
       raise errors.OpPrereqError("iallocator '%s' returned invalid number"
                                  " of nodes (%s), required %s" %
-                                 (len(ial.nodes), ial.required_nodes))
+                                 (iallocator_name,
+                                  len(ial.nodes), ial.required_nodes),
+                                 errors.ECODE_FAULT)
 
     remote_node_name = ial.nodes[0]
 
@@ -6372,13 +6589,27 @@ class TLReplaceDisks(Tasklet):
 
     if instance.disk_template != constants.DT_DRBD8:
       raise errors.OpPrereqError("Can only run replace disks for DRBD8-based"
-                                 " instances")
+                                 " instances", errors.ECODE_INVAL)
 
     if len(instance.secondary_nodes) != 1:
       raise errors.OpPrereqError("The instance has a strange layout,"
                                  " expected one secondary but found %d" %
-                                 len(instance.secondary_nodes))
+                                 len(instance.secondary_nodes),
+                                 errors.ECODE_FAULT)
+
+    if not self.delay_iallocator:
+      self._CheckPrereq2()
 
+  def _CheckPrereq2(self):
+    """Check prerequisites, second part.
+
+    This function should always be part of CheckPrereq. It was separated and is
+    now called from Exec because during node evacuation iallocator was only
+    called with an unmodified cluster model, not taking planned changes into
+    account.
+
+    """
+    instance = self.instance
     secondary_node = instance.secondary_nodes[0]
 
     if self.iallocator_name is None:
@@ -6396,15 +6627,17 @@ class TLReplaceDisks(Tasklet):
 
     if remote_node == self.instance.primary_node:
       raise errors.OpPrereqError("The specified node is the primary node of"
-                                 " the instance.")
+                                 " the instance.", errors.ECODE_INVAL)
 
     if remote_node == secondary_node:
       raise errors.OpPrereqError("The specified node is already the"
-                                 " secondary node of the instance.")
+                                 " secondary node of the instance.",
+                                 errors.ECODE_INVAL)
 
     if self.disks and self.mode in (constants.REPLACE_DISK_AUTO,
                                     constants.REPLACE_DISK_CHG):
-      raise errors.OpPrereqError("Cannot specify disks to be replaced")
+      raise errors.OpPrereqError("Cannot specify disks to be replaced",
+                                 errors.ECODE_INVAL)
 
     if self.mode == constants.REPLACE_DISK_AUTO:
       faulty_primary = self._FindFaultyDisks(instance.primary_node)
@@ -6413,7 +6646,8 @@ class TLReplaceDisks(Tasklet):
       if faulty_primary and faulty_secondary:
         raise errors.OpPrereqError("Instance %s has faulty disks on more than"
                                    " one node and can not be repaired"
-                                   " automatically" % self.instance_name)
+                                   " automatically" % self.instance_name,
+                                   errors.ECODE_STATE)
 
       if faulty_primary:
         self.disks = faulty_primary
@@ -6479,12 +6713,15 @@ class TLReplaceDisks(Tasklet):
     This dispatches the disk replacement to the appropriate handler.
 
     """
+    if self.delay_iallocator:
+      self._CheckPrereq2()
+
     if not self.disks:
       feedback_fn("No disks need replacement")
       return
 
     feedback_fn("Replacing disk(s) %s for %s" %
-                (", ".join([str(i) for i in self.disks]), self.instance.name))
+                (utils.CommaJoin(self.disks), self.instance.name))
 
     activate_disks = (not self.instance.admin_up)
 
@@ -6502,7 +6739,8 @@ class TLReplaceDisks(Tasklet):
       return fn(feedback_fn)
 
     finally:
-      # Deactivate the instance disks if we're replacing them on a down instance
+      # Deactivate the instance disks if we're replacing them on a
+      # down instance
       if activate_disks:
         _SafeShutdownInstanceDisks(self.lu, self.instance)
 
@@ -6588,7 +6826,7 @@ class TLReplaceDisks(Tasklet):
     return iv_names
 
   def _CheckDevices(self, node_name, iv_names):
-    for name, (dev, old_lvs, new_lvs) in iv_names.iteritems():
+    for name, (dev, _, _) in iv_names.iteritems():
       self.cfg.SetDiskID(dev, node_name)
 
       result = self.rpc.call_blockdev_find(node_name, dev)
@@ -6604,7 +6842,7 @@ class TLReplaceDisks(Tasklet):
         raise errors.OpExecError("DRBD device %s is degraded!" % name)
 
   def _RemoveOldStorage(self, node_name, iv_names):
-    for name, (dev, old_lvs, _) in iv_names.iteritems():
+    for name, (_, old_lvs, _) in iv_names.iteritems():
       self.lu.LogInfo("Remove logical volumes for %s" % name)
 
       for lv in old_lvs:
@@ -6729,7 +6967,7 @@ class TLReplaceDisks(Tasklet):
     # This can fail as the old devices are degraded and _WaitForSync
     # does a combined result over all disks, so we don't check its return value
     self.lu.LogStep(5, steps_total, "Sync devices")
-    _WaitForSync(self.lu, self.instance, unlock=True)
+    _WaitForSync(self.lu, self.instance)
 
     # Check all devices manually
     self._CheckDevices(self.instance.primary_node, iv_names)
@@ -6785,7 +7023,7 @@ class TLReplaceDisks(Tasklet):
     minors = self.cfg.AllocateDRBDMinor([self.new_node
                                          for dev in self.instance.disks],
                                         self.instance.name)
-    logging.debug("Allocated minors %r" % (minors,))
+    logging.debug("Allocated minors %r", minors)
 
     iv_names = {}
     for idx, (dev, new_minor) in enumerate(zip(self.instance.disks, minors)):
@@ -6799,6 +7037,7 @@ class TLReplaceDisks(Tasklet):
       if self.instance.primary_node == o_node1:
         p_minor = o_minor1
       else:
+        assert self.instance.primary_node == o_node2, "Three-node instance?"
         p_minor = o_minor2
 
       new_alone_id = (self.instance.primary_node, self.new_node, None,
@@ -6874,7 +7113,7 @@ class TLReplaceDisks(Tasklet):
     # This can fail as the old devices are degraded and _WaitForSync
     # does a combined result over all disks, so we don't check its return value
     self.lu.LogStep(5, steps_total, "Sync devices")
-    _WaitForSync(self.lu, self.instance, unlock=True)
+    _WaitForSync(self.lu, self.instance)
 
     # Check all devices manually
     self._CheckDevices(self.instance.primary_node, iv_names)
@@ -6894,7 +7133,8 @@ class LURepairNodeStorage(NoHooksLU):
   def CheckArguments(self):
     node_name = self.cfg.ExpandNodeName(self.op.node_name)
     if node_name is None:
-      raise errors.OpPrereqError("Invalid node name '%s'" % self.op.node_name)
+      raise errors.OpPrereqError("Invalid node name '%s'" % self.op.node_name,
+                                 errors.ECODE_NOENT)
 
     self.op.node_name = node_name
 
@@ -6904,10 +7144,18 @@ class LURepairNodeStorage(NoHooksLU):
       }
 
   def _CheckFaultyDisks(self, instance, node_name):
-    if _FindFaultyInstanceDisks(self.cfg, self.rpc, instance,
-                                node_name, True):
-      raise errors.OpPrereqError("Instance '%s' has faulty disks on"
-                                 " node '%s'" % (instance.name, node_name))
+    """Ensure faulty disks abort the opcode or at least warn."""
+    try:
+      if _FindFaultyInstanceDisks(self.cfg, self.rpc, instance,
+                                  node_name, True):
+        raise errors.OpPrereqError("Instance '%s' has faulty disks on"
+                                   " node '%s'" % (instance.name, node_name),
+                                   errors.ECODE_STATE)
+    except errors.OpPrereqError, err:
+      if self.op.ignore_consistency:
+        self.proc.LogWarning(str(err.args[0]))
+      else:
+        raise
 
   def CheckPrereq(self):
     """Check prerequisites.
@@ -6918,10 +7166,13 @@ class LURepairNodeStorage(NoHooksLU):
     if (constants.SO_FIX_CONSISTENCY not in
         constants.VALID_STORAGE_OPERATIONS.get(storage_type, [])):
       raise errors.OpPrereqError("Storage units of type '%s' can not be"
-                                 " repaired" % storage_type)
+                                 " repaired" % storage_type,
+                                 errors.ECODE_INVAL)
 
     # Check whether any instance on this node has faulty disks
     for inst in _GetNodeInstances(self.cfg, self.op.node_name):
+      if not inst.admin_up:
+        continue
       check_nodes = set(inst.all_nodes)
       check_nodes.discard(self.op.node_name)
       for inst_node_name in check_nodes:
@@ -6993,7 +7244,7 @@ class LUGrowDisk(LogicalUnit):
 
     if instance.disk_template not in (constants.DT_PLAIN, constants.DT_DRBD8):
       raise errors.OpPrereqError("Instance's disk layout does not support"
-                                 " growing.")
+                                 " growing.", errors.ECODE_INVAL)
 
     self.disk = instance.FindDisk(self.op.disk)
 
@@ -7005,11 +7256,12 @@ class LUGrowDisk(LogicalUnit):
       vg_free = info.payload.get('vg_free', None)
       if not isinstance(vg_free, int):
         raise errors.OpPrereqError("Can't compute free disk space on"
-                                   " node %s" % node)
+                                   " node %s" % node, errors.ECODE_ENVIRON)
       if self.op.amount > vg_free:
         raise errors.OpPrereqError("Not enough disk space on target node %s:"
                                    " %d MiB available, %d MiB required" %
-                                   (node, vg_free, self.op.amount))
+                                   (node, vg_free, self.op.amount),
+                                   errors.ECODE_NORES)
 
   def Exec(self, feedback_fn):
     """Execute disk grow.
@@ -7021,6 +7273,14 @@ class LUGrowDisk(LogicalUnit):
       self.cfg.SetDiskID(disk, node)
       result = self.rpc.call_blockdev_grow(node, disk, self.op.amount)
       result.Raise("Grow request failed to node %s" % node)
+
+      # TODO: Rewrite code to work properly
+      # DRBD goes into sync mode for a short amount of time after executing the
+      # "resize" command. DRBD 8.x below version 8.0.13 contains a bug whereby
+      # calling "resize" in sync mode fails. Sleeping for a short amount of
+      # time is a work-around.
+      time.sleep(5)
+
     disk.RecordGrow(self.op.amount)
     self.cfg.Update(instance, feedback_fn)
     if self.op.wait_for_sync:
@@ -7042,14 +7302,16 @@ class LUQueryInstanceData(NoHooksLU):
     self.share_locks = dict.fromkeys(locking.LEVELS, 1)
 
     if not isinstance(self.op.instances, list):
-      raise errors.OpPrereqError("Invalid argument type 'instances'")
+      raise errors.OpPrereqError("Invalid argument type 'instances'",
+                                 errors.ECODE_INVAL)
 
     if self.op.instances:
       self.wanted_names = []
       for name in self.op.instances:
         full_name = self.cfg.ExpandInstanceName(name)
         if full_name is None:
-          raise errors.OpPrereqError("Instance '%s' not known" % name)
+          raise errors.OpPrereqError("Instance '%s' not known" % name,
+                                     errors.ECODE_NOENT)
         self.wanted_names.append(full_name)
       self.needed_locks[locking.LEVEL_INSTANCE] = self.wanted_names
     else:
@@ -7174,7 +7436,7 @@ class LUQueryInstanceData(NoHooksLU):
         "hypervisor": instance.hypervisor,
         "network_port": instance.network_port,
         "hv_instance": instance.hvparams,
-        "hv_actual": cluster.FillHV(instance),
+        "hv_actual": cluster.FillHV(instance, skip_globals=True),
         "be_instance": instance.beparams,
         "be_actual": cluster.FillBE(instance),
         "serial_no": instance.serial_no,
@@ -7209,7 +7471,10 @@ class LUSetInstanceParams(LogicalUnit):
     self.op.force = getattr(self.op, "force", False)
     if not (self.op.nics or self.op.disks or
             self.op.hvparams or self.op.beparams):
-      raise errors.OpPrereqError("No changes submitted")
+      raise errors.OpPrereqError("No changes submitted", errors.ECODE_INVAL)
+
+    if self.op.hvparams:
+      _CheckGlobalHvParams(self.op.hvparams)
 
     # Disk validation
     disk_addremove = 0
@@ -7221,33 +7486,35 @@ class LUSetInstanceParams(LogicalUnit):
         disk_addremove += 1
       else:
         if not isinstance(disk_op, int):
-          raise errors.OpPrereqError("Invalid disk index")
+          raise errors.OpPrereqError("Invalid disk index", errors.ECODE_INVAL)
         if not isinstance(disk_dict, dict):
           msg = "Invalid disk value: expected dict, got '%s'" % disk_dict
-          raise errors.OpPrereqError(msg)
+          raise errors.OpPrereqError(msg, errors.ECODE_INVAL)
 
       if disk_op == constants.DDM_ADD:
         mode = disk_dict.setdefault('mode', constants.DISK_RDWR)
         if mode not in constants.DISK_ACCESS_SET:
-          raise errors.OpPrereqError("Invalid disk access mode '%s'" % mode)
+          raise errors.OpPrereqError("Invalid disk access mode '%s'" % mode,
+                                     errors.ECODE_INVAL)
         size = disk_dict.get('size', None)
         if size is None:
-          raise errors.OpPrereqError("Required disk parameter size missing")
+          raise errors.OpPrereqError("Required disk parameter size missing",
+                                     errors.ECODE_INVAL)
         try:
           size = int(size)
-        except ValueError, err:
+        except (TypeError, ValueError), err:
           raise errors.OpPrereqError("Invalid disk size parameter: %s" %
-                                     str(err))
+                                     str(err), errors.ECODE_INVAL)
         disk_dict['size'] = size
       else:
         # modification of disk
         if 'size' in disk_dict:
           raise errors.OpPrereqError("Disk size change not possible, use"
-                                     " grow-disk")
+                                     " grow-disk", errors.ECODE_INVAL)
 
     if disk_addremove > 1:
       raise errors.OpPrereqError("Only one disk add or remove operation"
-                                 " supported at a time")
+                                 " supported at a time", errors.ECODE_INVAL)
 
     # NIC validation
     nic_addremove = 0
@@ -7259,10 +7526,10 @@ class LUSetInstanceParams(LogicalUnit):
         nic_addremove += 1
       else:
         if not isinstance(nic_op, int):
-          raise errors.OpPrereqError("Invalid nic index")
+          raise errors.OpPrereqError("Invalid nic index", errors.ECODE_INVAL)
         if not isinstance(nic_dict, dict):
           msg = "Invalid nic value: expected dict, got '%s'" % nic_dict
-          raise errors.OpPrereqError(msg)
+          raise errors.OpPrereqError(msg, errors.ECODE_INVAL)
 
       # nic_dict should be a dict
       nic_ip = nic_dict.get('ip', None)
@@ -7271,13 +7538,14 @@ class LUSetInstanceParams(LogicalUnit):
           nic_dict['ip'] = None
         else:
           if not utils.IsValidIP(nic_ip):
-            raise errors.OpPrereqError("Invalid IP address '%s'" % nic_ip)
+            raise errors.OpPrereqError("Invalid IP address '%s'" % nic_ip,
+                                       errors.ECODE_INVAL)
 
       nic_bridge = nic_dict.get('bridge', None)
       nic_link = nic_dict.get('link', None)
       if nic_bridge and nic_link:
         raise errors.OpPrereqError("Cannot pass 'bridge' and 'link'"
-                                   " at the same time")
+                                   " at the same time", errors.ECODE_INVAL)
       elif nic_bridge and nic_bridge.lower() == constants.VALUE_NONE:
         nic_dict['bridge'] = None
       elif nic_link and nic_link.lower() == constants.VALUE_NONE:
@@ -7291,15 +7559,16 @@ class LUSetInstanceParams(LogicalUnit):
       if 'mac' in nic_dict:
         nic_mac = nic_dict['mac']
         if nic_mac not in (constants.VALUE_AUTO, constants.VALUE_GENERATE):
-          if not utils.IsValidMac(nic_mac):
-            raise errors.OpPrereqError("Invalid MAC address %s" % nic_mac)
+          nic_mac = utils.NormalizeAndValidateMac(nic_mac)
+
         if nic_op != constants.DDM_ADD and nic_mac == constants.VALUE_AUTO:
           raise errors.OpPrereqError("'auto' is not a valid MAC address when"
-                                     " modifying an existing nic")
+                                     " modifying an existing nic",
+                                     errors.ECODE_INVAL)
 
     if nic_addremove > 1:
       raise errors.OpPrereqError("Only one NIC add or remove operation"
-                                 " supported at a time")
+                                 " supported at a time", errors.ECODE_INVAL)
 
   def ExpandNames(self):
     self._ExpandAndLockInstance()
@@ -7361,7 +7630,8 @@ class LUSetInstanceParams(LogicalUnit):
     nl = [self.cfg.GetMasterNode()] + list(self.instance.all_nodes)
     return env, nl, nl
 
-  def _GetUpdatedParams(self, old_params, update_dict,
+  @staticmethod
+  def _GetUpdatedParams(old_params, update_dict,
                         default_values, parameter_types):
     """Return the new params dict for the given params.
 
@@ -7472,7 +7742,8 @@ class LUSetInstanceParams(LogicalUnit):
         if miss_mem > 0:
           raise errors.OpPrereqError("This change will prevent the instance"
                                      " from starting, due to %d MB of memory"
-                                     " missing on its primary node" % miss_mem)
+                                     " missing on its primary node" % miss_mem,
+                                     errors.ECODE_NORES)
 
       if be_new[constants.BE_AUTO_BALANCE]:
         for node, nres in nodeinfo.items():
@@ -7495,14 +7766,20 @@ class LUSetInstanceParams(LogicalUnit):
     for nic_op, nic_dict in self.op.nics:
       if nic_op == constants.DDM_REMOVE:
         if not instance.nics:
-          raise errors.OpPrereqError("Instance has no NICs, cannot remove")
+          raise errors.OpPrereqError("Instance has no NICs, cannot remove",
+                                     errors.ECODE_INVAL)
         continue
       if nic_op != constants.DDM_ADD:
         # an existing nic
+        if not instance.nics:
+          raise errors.OpPrereqError("Invalid NIC index %s, instance has"
+                                     " no NICs" % nic_op,
+                                     errors.ECODE_INVAL)
         if nic_op < 0 or nic_op >= len(instance.nics):
           raise errors.OpPrereqError("Invalid NIC index %s, valid values"
                                      " are 0 to %d" %
-                                     (nic_op, len(instance.nics)))
+                                     (nic_op, len(instance.nics) - 1),
+                                     errors.ECODE_INVAL)
         old_nic_params = instance.nics[nic_op].nicparams
         old_nic_ip = instance.nics[nic_op].ip
       else:
@@ -7533,7 +7810,7 @@ class LUSetInstanceParams(LogicalUnit):
           if self.force:
             self.warn.append(msg)
           else:
-            raise errors.OpPrereqError(msg)
+            raise errors.OpPrereqError(msg, errors.ECODE_ENVIRON)
       if new_nic_mode == constants.NIC_MODE_ROUTED:
         if 'ip' in nic_dict:
           nic_ip = nic_dict['ip']
@@ -7541,49 +7818,57 @@ class LUSetInstanceParams(LogicalUnit):
           nic_ip = old_nic_ip
         if nic_ip is None:
           raise errors.OpPrereqError('Cannot set the nic ip to None'
-                                     ' on a routed nic')
+                                     ' on a routed nic', errors.ECODE_INVAL)
       if 'mac' in nic_dict:
         nic_mac = nic_dict['mac']
         if nic_mac is None:
-          raise errors.OpPrereqError('Cannot set the nic mac to None')
+          raise errors.OpPrereqError('Cannot set the nic mac to None',
+                                     errors.ECODE_INVAL)
         elif nic_mac in (constants.VALUE_AUTO, constants.VALUE_GENERATE):
           # otherwise generate the mac
-          nic_dict['mac'] = self.cfg.GenerateMAC()
+          nic_dict['mac'] = self.cfg.GenerateMAC(self.proc.GetECId())
         else:
           # or validate/reserve the current one
-          if self.cfg.IsMacInUse(nic_mac):
+          try:
+            self.cfg.ReserveMAC(nic_mac, self.proc.GetECId())
+          except errors.ReservationError:
             raise errors.OpPrereqError("MAC address %s already in use"
-                                       " in cluster" % nic_mac)
+                                       " in cluster" % nic_mac,
+                                       errors.ECODE_NOTUNIQUE)
 
     # DISK processing
     if self.op.disks and instance.disk_template == constants.DT_DISKLESS:
       raise errors.OpPrereqError("Disk operations not supported for"
-                                 " diskless instances")
-    for disk_op, disk_dict in self.op.disks:
+                                 " diskless instances",
+                                 errors.ECODE_INVAL)
+    for disk_op, _ in self.op.disks:
       if disk_op == constants.DDM_REMOVE:
         if len(instance.disks) == 1:
           raise errors.OpPrereqError("Cannot remove the last disk of"
-                                     " an instance")
+                                     " an instance",
+                                     errors.ECODE_INVAL)
         ins_l = self.rpc.call_instance_list([pnode], [instance.hypervisor])
         ins_l = ins_l[pnode]
         msg = ins_l.fail_msg
         if msg:
           raise errors.OpPrereqError("Can't contact node %s: %s" %
-                                     (pnode, msg))
+                                     (pnode, msg), errors.ECODE_ENVIRON)
         if instance.name in ins_l.payload:
           raise errors.OpPrereqError("Instance is running, can't remove"
-                                     " disks.")
+                                     " disks.", errors.ECODE_STATE)
 
       if (disk_op == constants.DDM_ADD and
           len(instance.nics) >= constants.MAX_DISKS):
         raise errors.OpPrereqError("Instance has too many disks (%d), cannot"
-                                   " add more" % constants.MAX_DISKS)
+                                   " add more" % constants.MAX_DISKS,
+                                   errors.ECODE_STATE)
       if disk_op not in (constants.DDM_ADD, constants.DDM_REMOVE):
         # an existing disk
         if disk_op < 0 or disk_op >= len(instance.disks):
           raise errors.OpPrereqError("Invalid disk index %s, valid values"
                                      " are 0 to %d" %
-                                     (disk_op, len(instance.disks)))
+                                     (disk_op, len(instance.disks)),
+                                     errors.ECODE_INVAL)
 
     return
 
@@ -7600,7 +7885,6 @@ class LUSetInstanceParams(LogicalUnit):
 
     result = []
     instance = self.instance
-    cluster = self.cluster
     # disk changes
     for disk_op, disk_dict in self.op.disks:
       if disk_op == constants.DDM_REMOVE:
@@ -7675,8 +7959,8 @@ class LUSetInstanceParams(LogicalUnit):
         for key in 'mac', 'ip':
           if key in nic_dict:
             setattr(instance.nics[nic_op], key, nic_dict[key])
-        if nic_op in self.nic_pnew:
-          instance.nics[nic_op].nicparams = self.nic_pnew[nic_op]
+        if nic_op in self.nic_pinst:
+          instance.nics[nic_op].nicparams = self.nic_pinst[nic_op]
         for key, val in nic_dict.iteritems():
           result.append(("nic.%s/%d" % (key, nic_op), val))
 
@@ -7804,7 +8088,8 @@ class LUExportInstance(LogicalUnit):
 
     if self.dst_node is None:
       # This is wrong node name, not a non-locked node
-      raise errors.OpPrereqError("Wrong node name %s" % self.op.target_node)
+      raise errors.OpPrereqError("Wrong node name %s" % self.op.target_node,
+                                 errors.ECODE_NOENT)
     _CheckNodeOnline(self, self.dst_node.name)
     _CheckNodeNotDrained(self, self.dst_node.name)
 
@@ -7812,7 +8097,7 @@ class LUExportInstance(LogicalUnit):
     for disk in self.instance.disks:
       if disk.dev_type == constants.LD_FILE:
         raise errors.OpPrereqError("Export not supported for instances with"
-                                   " file-based disks")
+                                   " file-based disks", errors.ECODE_INVAL)
 
   def Exec(self, feedback_fn):
     """Export an instance to an image in the cluster.
@@ -7885,8 +8170,10 @@ class LUExportInstance(LogicalUnit):
         feedback_fn("Exporting snapshot %s from %s to %s" %
                     (idx, src_node, dst_node.name))
         if dev:
+          # FIXME: pass debug from opcode to backend
           result = self.rpc.call_snapshot_export(src_node, dev, dst_node.name,
-                                                 instance, cluster_name, idx)
+                                                 instance, cluster_name,
+                                                 idx, 0)
           msg = result.fail_msg
           if msg:
             self.LogWarning("Could not export disk/%s from node %s to"
@@ -7990,7 +8277,7 @@ class LURemoveExport(NoHooksLU):
                   " Domain Name.")
 
 
-class TagsLU(NoHooksLU):
+class TagsLU(NoHooksLU): # pylint: disable-msg=W0223
   """Generic tags LU.
 
   This is an abstract class which is the parent of all the other tags LUs.
@@ -8003,14 +8290,14 @@ class TagsLU(NoHooksLU):
       name = self.cfg.ExpandNodeName(self.op.name)
       if name is None:
         raise errors.OpPrereqError("Invalid node name (%s)" %
-                                   (self.op.name,))
+                                   (self.op.name,), errors.ECODE_NOENT)
       self.op.name = name
       self.needed_locks[locking.LEVEL_NODE] = name
     elif self.op.kind == constants.TAG_INSTANCE:
       name = self.cfg.ExpandInstanceName(self.op.name)
       if name is None:
         raise errors.OpPrereqError("Invalid instance name (%s)" %
-                                   (self.op.name,))
+                                   (self.op.name,), errors.ECODE_NOENT)
       self.op.name = name
       self.needed_locks[locking.LEVEL_INSTANCE] = name
 
@@ -8026,7 +8313,7 @@ class TagsLU(NoHooksLU):
       self.target = self.cfg.GetInstanceInfo(self.op.name)
     else:
       raise errors.OpPrereqError("Wrong tag type requested (%s)" %
-                                 str(self.op.kind))
+                                 str(self.op.kind), errors.ECODE_INVAL)
 
 
 class LUGetTags(TagsLU):
@@ -8063,7 +8350,7 @@ class LUSearchTags(NoHooksLU):
       self.re = re.compile(self.op.pattern)
     except re.error, err:
       raise errors.OpPrereqError("Invalid search pattern '%s': %s" %
-                                 (self.op.pattern, err))
+                                 (self.op.pattern, err), errors.ECODE_INVAL)
 
   def Exec(self, feedback_fn):
     """Returns the tag list.
@@ -8109,12 +8396,7 @@ class LUAddTags(TagsLU):
         self.target.AddTag(tag)
     except errors.TagError, err:
       raise errors.OpExecError("Error while setting tag: %s" % str(err))
-    try:
-      self.cfg.Update(self.target, feedback_fn)
-    except errors.ConfigurationError:
-      raise errors.OpRetryError("There has been a modification to the"
-                                " config file and the operation has been"
-                                " aborted. Please retry.")
+    self.cfg.Update(self.target, feedback_fn)
 
 
 class LUDelTags(TagsLU):
@@ -8140,7 +8422,7 @@ class LUDelTags(TagsLU):
       diff_names = ["'%s'" % tag for tag in diff_tags]
       diff_names.sort()
       raise errors.OpPrereqError("Tag(s) %s not found" %
-                                 (",".join(diff_names)))
+                                 (",".join(diff_names)), errors.ECODE_NOENT)
 
   def Exec(self, feedback_fn):
     """Remove the tag from the object.
@@ -8148,12 +8430,7 @@ class LUDelTags(TagsLU):
     """
     for tag in self.op.tags:
       self.target.RemoveTag(tag)
-    try:
-      self.cfg.Update(self.target, feedback_fn)
-    except errors.ConfigurationError:
-      raise errors.OpRetryError("There has been a modification to the"
-                                " config file and the operation has been"
-                                " aborted. Please retry.")
+    self.cfg.Update(self.target, feedback_fn)
 
 
 class LUTestDelay(NoHooksLU):
@@ -8211,6 +8488,8 @@ class IAllocator(object):
       easy usage
 
   """
+  # pylint: disable-msg=R0902
+  # lots of instance attributes
   _ALLO_KEYS = [
     "mem_size", "disks", "disk_template",
     "os", "tags", "nics", "vcpus", "hypervisor",
@@ -8429,10 +8708,12 @@ class IAllocator(object):
                                    " IAllocator" % self.name)
 
     if instance.disk_template not in constants.DTS_NET_MIRROR:
-      raise errors.OpPrereqError("Can't relocate non-mirrored instances")
+      raise errors.OpPrereqError("Can't relocate non-mirrored instances",
+                                 errors.ECODE_INVAL)
 
     if len(instance.secondary_nodes) != 1:
-      raise errors.OpPrereqError("Instance has not exactly one secondary node")
+      raise errors.OpPrereqError("Instance has not exactly one secondary node",
+                                 errors.ECODE_STATE)
 
     self.required_nodes = 1
     disk_sizes = [{'size': disk.size} for disk in instance.disks]
@@ -8520,51 +8801,55 @@ class LUTestAllocator(NoHooksLU):
                    "os", "tags", "nics", "vcpus"]:
         if not hasattr(self.op, attr):
           raise errors.OpPrereqError("Missing attribute '%s' on opcode input" %
-                                     attr)
+                                     attr, errors.ECODE_INVAL)
       iname = self.cfg.ExpandInstanceName(self.op.name)
       if iname is not None:
         raise errors.OpPrereqError("Instance '%s' already in the cluster" %
-                                   iname)
+                                   iname, errors.ECODE_EXISTS)
       if not isinstance(self.op.nics, list):
-        raise errors.OpPrereqError("Invalid parameter 'nics'")
+        raise errors.OpPrereqError("Invalid parameter 'nics'",
+                                   errors.ECODE_INVAL)
       for row in self.op.nics:
         if (not isinstance(row, dict) or
             "mac" not in row or
             "ip" not in row or
             "bridge" not in row):
-          raise errors.OpPrereqError("Invalid contents of the"
-                                     " 'nics' parameter")
+          raise errors.OpPrereqError("Invalid contents of the 'nics'"
+                                     " parameter", errors.ECODE_INVAL)
       if not isinstance(self.op.disks, list):
-        raise errors.OpPrereqError("Invalid parameter 'disks'")
+        raise errors.OpPrereqError("Invalid parameter 'disks'",
+                                   errors.ECODE_INVAL)
       for row in self.op.disks:
         if (not isinstance(row, dict) or
             "size" not in row or
             not isinstance(row["size"], int) or
             "mode" not in row or
             row["mode"] not in ['r', 'w']):
-          raise errors.OpPrereqError("Invalid contents of the"
-                                     " 'disks' parameter")
+          raise errors.OpPrereqError("Invalid contents of the 'disks'"
+                                     " parameter", errors.ECODE_INVAL)
       if not hasattr(self.op, "hypervisor") or self.op.hypervisor is None:
         self.op.hypervisor = self.cfg.GetHypervisorType()
     elif self.op.mode == constants.IALLOCATOR_MODE_RELOC:
       if not hasattr(self.op, "name"):
-        raise errors.OpPrereqError("Missing attribute 'name' on opcode input")
+        raise errors.OpPrereqError("Missing attribute 'name' on opcode input",
+                                   errors.ECODE_INVAL)
       fname = self.cfg.ExpandInstanceName(self.op.name)
       if fname is None:
         raise errors.OpPrereqError("Instance '%s' not found for relocation" %
-                                   self.op.name)
+                                   self.op.name, errors.ECODE_NOENT)
       self.op.name = fname
       self.relocate_from = self.cfg.GetInstanceInfo(fname).secondary_nodes
     else:
       raise errors.OpPrereqError("Invalid test allocator mode '%s'" %
-                                 self.op.mode)
+                                 self.op.mode, errors.ECODE_INVAL)
 
     if self.op.direction == constants.IALLOCATOR_DIR_OUT:
       if not hasattr(self.op, "allocator") or self.op.allocator is None:
-        raise errors.OpPrereqError("Missing allocator name")
+        raise errors.OpPrereqError("Missing allocator name",
+                                   errors.ECODE_INVAL)
     elif self.op.direction != constants.IALLOCATOR_DIR_IN:
       raise errors.OpPrereqError("Wrong allocator test '%s'" %
-                                 self.op.direction)
+                                 self.op.direction, errors.ECODE_INVAL)
 
   def Exec(self, feedback_fn):
     """Run the allocator test.