Synnefo » snf-ganeti » ganeti-local

  # timeout constants

  _NET_RECONFIG_TIMEOUT = 60

  def DisconnectNet(self):

    """Removes network configuration.

    This method shutdowns the network side of the device.

    The method will wait up to a hardcoded timeout for the device to

    go into standalone after the 'disconnect' command before

    re-configuring it, as sometimes it takes a while for the

    disconnect to actually propagate and thus we might issue a 'net'

    command while the device is still connected. If the device will

    still be attached to the network and we time out, we raise an

    exception.

    """

    if self.minor is None:

      raise errors.BlockDeviceError("DRBD disk not attached in re-attach net")

    if None in (self._lhost, self._lport, self._rhost, self._rport):

      raise errors.BlockDeviceError("DRBD disk missing network info in"

                                    " DisconnectNet()")

    ever_disconnected = self._ShutdownNet(self.minor)

    timeout_limit = time.time() + self._NET_RECONFIG_TIMEOUT

    sleep_time = 0.100 # we start the retry time at 100 miliseconds

    while time.time() < timeout_limit:

      status = self.GetProcStatus()

      if status.is_standalone:

        break

      # retry the disconnect, it seems possible that due to a

      # well-time disconnect on the peer, my disconnect command might

      # be ingored and forgotten

      ever_disconnected = self._ShutdownNet(self.minor) or ever_disconnected

      time.sleep(sleep_time)

      sleep_time = min(2, sleep_time * 1.5)

    if not status.is_standalone:

      if ever_disconnected:

        msg = ("Device did not react to the"

               " 'disconnect' command in a timely manner")

      else:

        msg = ("Can't shutdown network, even after multiple retries")

      raise errors.BlockDeviceError(msg)

    reconfig_time = time.time() - timeout_limit + self._NET_RECONFIG_TIMEOUT

    if reconfig_time > 15: # hardcoded alert limit

      logging.debug("DRBD8.DisconnectNet: detach took %.3f seconds",

                    reconfig_time)

  def AttachNet(self, multimaster):

    """Reconnects the network.

    This method connects the network side of the device with a

    specified multi-master flag. The device needs to be 'Standalone'

    but have valid network configuration data.

    Args:

      - multimaster: init the network in dual-primary mode

    """

    if self.minor is None:

      raise errors.BlockDeviceError("DRBD disk not attached in AttachNet")

    if None in (self._lhost, self._lport, self._rhost, self._rport):

      raise errors.BlockDeviceError("DRBD disk missing network info in"

                                    " AttachNet()")

    status = self.GetProcStatus()

    if not status.is_standalone:

      raise errors.BlockDeviceError("Device is not standalone in AttachNet")

    return self._AssembleNet(self.minor,

                             (self._lhost, self._lport,

                              self._rhost, self._rport),

                             "C", dual_pri=multimaster)