Synnefo » snf-ganeti

def _PerformNodeInfoCall(lu, node_uuids, vg):

  """Prepares the input and performs a node info call.

  @type lu: C{LogicalUnit}

  @param lu: a logical unit from which we get configuration data

  @type node_uuids: list of string

  @param node_uuids: list of node UUIDs to perform the call for

  @type vg: string

  @param vg: the volume group's name

  """

  lvm_storage_units = [(constants.ST_LVM_VG, vg)]

  storage_units = rpc.PrepareStorageUnitsForNodes(lu.cfg, lvm_storage_units,

                                                  node_uuids)

  hvname = lu.cfg.GetHypervisorType()

  hvparams = lu.cfg.GetClusterInfo().hvparams

  nodeinfo = lu.rpc.call_node_info(node_uuids, storage_units,

                                   [(hvname, hvparams[hvname])])

  return nodeinfo

def _CheckVgCapacityForNode(node_name, node_info, vg, requested):

  """Checks the vg capacity for a given node.

  @type node_info: tuple (_, list of dicts, _)

  @param node_info: the result of the node info call for one node

  @type node_name: string

  @param node_name: the name of the node

  @type vg: string

  @param vg: volume group name

  @type requested: int

  @param requested: the amount of disk in MiB to check for

  @raise errors.OpPrereqError: if the node doesn't have enough disk,

      or we cannot check the node

  """

  (_, space_info, _) = node_info

  lvm_vg_info = utils.storage.LookupSpaceInfoByStorageType(

      space_info, constants.ST_LVM_VG)

  if not lvm_vg_info:

    raise errors.OpPrereqError("Can't retrieve storage information for LVM")

  vg_free = lvm_vg_info.get("storage_free", None)

  if not isinstance(vg_free, int):

    raise errors.OpPrereqError("Can't compute free disk space on node"

                               " %s for vg %s, result was '%s'" %

                               (node_name, vg, vg_free), errors.ECODE_ENVIRON)

  if requested > vg_free:

    raise errors.OpPrereqError("Not enough disk space on target node %s"

                               " vg %s: required %d MiB, available %d MiB" %

                               (node_name, vg, requested, vg_free),

                               errors.ECODE_NORES)

  nodeinfo = _PerformNodeInfoCall(lu, node_uuids, vg)

    _CheckVgCapacityForNode(node_name, info.payload, vg, requested)