hadoop/bin/refresh-namenodes.sh

#!/usr/bin/env bash

# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.


# ------------------------------------------------------------------
# This script refreshes all namenodes, it's a simple wrapper
# for dfsadmin to support multiple namenodes.

bin=`dirname "$0"`
bin=`cd "$bin"; pwd`

. "$bin/hdfs-config.sh"

namenodes=$("$HADOOP_HOME/bin/hdfs" getconf -namenodes)

for namenode in $namenodes ; do
  echo "Refreshing namenode [$namenode]"
  "$HADOOP_HOME/bin/hdfs" dfsadmin -refreshNodes
  if [ "$?" != '0' ] ; then errorFlag='1' ; fi
done

if [ "$errorFlag" = '1' ] ; then
  echo "Error: refresh of namenodes failed, see error messages above."
  exit 1
else
  echo "Refresh of all namenodes succeeded."
fi


# eof