Synnefo » snf-ganeti

import logging

  This function must be called before the actual opcode, and will ssh

  to the remote node, copy the needed files, and start ganeti-noded,

  allowing the master to do the rest via normal rpc calls.

def MasterFailover():

  """Failover the master node.

  This checks that we are not already the master, and will cause the

  current master to cease being master, and the non-master to become

  new master.

  """

  ss = ssconf.WritableSimpleStore()

  new_master = utils.HostInfo().name

  old_master = ss.GetMasterNode()

  if old_master == new_master:

    raise errors.OpPrereqError("This commands must be run on the node"

                               " where you want the new master to be."

                               " %s is already the master" %

                               old_master)

  # end checks

  rcode = 0

  logging.info("setting master to %s, old master: %s", new_master, old_master)

  if not rpc.call_node_stop_master(old_master, True):

    logging.error("could disable the master role on the old master"

                 " %s, please disable manually", old_master)

  ss.SetKey(ss.SS_MASTER_NODE, new_master)

  cfg = config.ConfigWriter()

  if not rpc.call_upload_file(cfg.GetNodeList(),

                              ss.KeyToFilename(ss.SS_MASTER_NODE)):

    logger.Error("could not distribute the new simple store master file"

                 " to the other nodes, please check.")

  if not rpc.call_node_start_master(new_master, True):

    logging.error("could not start the master role on the new master"

                  " %s, please check", new_master)

    rcode = 1

  return rcode