Synnefo » snf-ganeti

def _CheckNodesFreeDisk(lu, nodenames, requested):

  """Checks if nodes have enough free disk space in the default VG.

  This function check if all given nodes have the needed amount of

  free disk. In case any node has less disk or we cannot get the

  information from the node, this function raise an OpPrereqError

  exception.

  @type lu: C{LogicalUnit}

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

  @type nodenames: C{list}

  @param nodenames: the list of node names to check

  @type requested: C{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

  """

  nodeinfo = lu.rpc.call_node_info(nodenames, lu.cfg.GetVGName(),

                                   lu.cfg.GetHypervisorType())

  for node in nodenames:

    info = nodeinfo[node]

    info.Raise("Cannot get current information from node %s" % node,

               prereq=True, ecode=errors.ECODE_ENVIRON)

    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,"

                                 " result was '%s'" % (node, vg_free),

                                 errors.ECODE_ENVIRON)

    if requested > vg_free:

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

                                 " required %d MiB, available %d MiB" %

                                 (node, requested, vg_free),

                                 errors.ECODE_NORES)