我在我的EC2实例中安装了Sqoop，引用了http://kontext.tech/docs/DataAndBusinessIntelligence/p/configure-sqoop-in-a-edge-node-of-hadoop-cluster我的hadoop集群也运行良好。
我收到了错误Error: Could not find or load main class org.apache.hadoop.mapreduce.v2.app.MRAppMaster，我用该特定链接中提到的解决方案解决了它。但不幸的是，在运行Sqoop Import时出现了另一个错误：
Container exited with a non-zero exit code 1. Error file: prelaunch.err.
Last 4096 bytes of prelaunch.err :
Last 4096 bytes of stderr :
Error: Could not find or load main class org.apache.hadoop.mapred.YarnChild。
请建议我如何克服此错误。
这就是我的sqoop-env.template.sh看起来的样子：
# 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.
# included in all the hadoop scripts with source command
# should not be executable directly
# also should not be passed any arguments, since we need original $*
# Set Hadoop-specific environment variables here.
#Set path to where bin/hadoop is available
#export HADOOP_COMMON_HOME=$HOME/hadoop-3.1.0
#Set path to where hadoop-*-core.jar is available
#export HADOOP_MAPRED_HOME=$HOME/hadoop-3.1.0
#set the path to where bin/hbase is available
#export HBASE_HOME=
#Set the path to where bin/hive is available
#export HIVE_HOME=
#Set the path for where zookeper config dir is
#export ZOOCFGDIR=`