sqoop导入mysql到HDFS时报错：java.lang.NoClassDefFoundError: org/json/JSONObject

问题1：sqoop import导入时报java.lang.ClassNotFoundException: org.json.JSONObject 错误

[root@hadoop1 lib]# sqoop import --connect jdbc:mysql://10.1.32.8:3306/test --username sqoop --password sqoop --table t1 -m 1
16/06/07 08:48:59 INFO sqoop.Sqoop: Running Sqoop version: 1.4.6-cdh5.7.0
16/06/07 08:48:59 WARN tool.BaseSqoopTool: Setting your password on the command-line is insecure. Consider using -P instead.
16/06/07 08:48:59 INFO manager.MySQLManager: Preparing to use a MySQL streaming resultset.
16/06/07 08:48:59 INFO tool.CodeGenTool: Beginning code generation
16/06/07 08:48:59 INFO manager.SqlManager: Executing SQL statement: SELECT t.* FROM `t1` AS t LIMIT 1
16/06/07 08:48:59 INFO manager.SqlManager: Executing SQL statement: SELECT t.* FROM `t1` AS t LIMIT 1
16/06/07 08:48:59 INFO orm.CompilationManager: HADOOP_MAPRED_HOME is /opt/cloudera/parcels/CDH/lib/hadoop-mapreduce
Note: /tmp/sqoop-root/compile/07751371c513f90a6377d7b482c4a910/t1.java uses or overrides a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
16/06/07 08:49:01 INFO orm.CompilationManager: Writing jar file: /tmp/sqoop-root/compile/07751371c513f90a6377d7b482c4a910/t1.jar
16/06/07 08:49:01 WARN manager.MySQLManager: It looks like you are importing from mysql.
16/06/07 08:49:01 WARN manager.MySQLManager: This transfer can be faster! Use the --direct
16/06/07 08:49:01 WARN manager.MySQLManager: option to exercise a MySQL-specific fast path.
16/06/07 08:49:01 INFO manager.MySQLManager: Setting zero DATETIME behavior to convertToNull (mysql)
16/06/07 08:49:01 INFO mapreduce.ImportJobBase: Beginning import of t1
Exception in thread "main" java.lang.NoClassDefFoundError: org/json/JSONObject
at org.apache.sqoop.util.SqoopJsonUtil.getJsonStringforMap(SqoopJsonUtil.java:42)
at org.apache.sqoop.SqoopOptions.writeProperties(SqoopOptions.java:742)
at org.apache.sqoop.mapreduce.JobBase.putSqoopOptionsToConfiguration(JobBase.java:369)
at org.apache.sqoop.mapreduce.JobBase.createJob(JobBase.java:355)
at org.apache.sqoop.mapreduce.ImportJobBase.runImport(ImportJobBase.java:249)
at org.apache.sqoop.manager.SqlManager.importTable(SqlManager.java:692)
at org.apache.sqoop.manager.MySQLManager.importTable(MySQLManager.java:118)
at org.apache.sqoop.tool.ImportTool.importTable(ImportTool.java:497)
at org.apache.sqoop.tool.ImportTool.run(ImportTool.java:605)
at org.apache.sqoop.Sqoop.run(Sqoop.java:143)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
at org.apache.sqoop.Sqoop.runSqoop(Sqoop.java:179)
at org.apache.sqoop.Sqoop.runTool(Sqoop.java:218)
at org.apache.sqoop.Sqoop.runTool(Sqoop.java:227)
at org.apache.sqoop.Sqoop.main(Sqoop.java:236)
Caused by: java.lang.ClassNotFoundException: org.json.JSONObject
at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
... 15 more

解决：
这是因为sqoop缺少java-json.jar包.
如下面链接所说：
http://stackoverflow.com/questions/27504508/java-lang-noclassdeffounderror-org-json-jsonobject

The Exception it self says itall java.lang.ClassNotFoundException: org.json.JSONObjectYou have not added thenecessary jar file which will be having org.json.JSONObject class to yourclasspath.
下载java-json.jar包：
http://www.java2s.com/Code/Jar/j/Downloadjavajsonjar.htm

把java-json.jar添加到../sqoop/lib目录：
# cp java-json.jar/opt/cloudera/parcels/CDH-5.7.0-1.cdh5.7.0.p0.45/lib/sqoop/lib
[hdfs@hadoop1 lib]# pwd
/opt/cloudera/parcels/CDH-5.7.0-1.cdh5.7.0.p0.45/lib/sqoop/lib
[hdfs@hadoop1 lib]#
[hdfs@hadoop1 lib]$ ll java-json.jar
-rw-r--r-- 1 root root 84697 Oct 16 2013 java-json.jar

问题2：root用户写入HDFS文件错误 "Permission denied: user=root"

[root@hadoop1 lib]# sqoop import --connect jdbc:mysql://10.1.32.8:3306/test --username sqoop --password sqoop --table t1 -m 1
16/06/07 08:49:50 INFO sqoop.Sqoop: Running Sqoop version: 1.4.6-cdh5.7.0
16/06/07 08:49:50 WARN tool.BaseSqoopTool: Setting your password on the command-line is insecure. Consider using -P instead.
... ...
16/06/07 08:49:52 INFO manager.MySQLManager: Setting zero DATETIME behavior to convertToNull (mysql)
16/06/07 08:49:52 INFO mapreduce.ImportJobBase: Beginning import of t1
16/06/07 08:49:53 INFO Configuration.deprecation: mapred.jar is deprecated. Instead, use mapreduce.job.jar
16/06/07 08:49:53 INFO Configuration.deprecation: mapred.map.tasks is deprecated. Instead, use mapreduce.job.maps
16/06/07 08:49:53 INFO client.RMProxy: Connecting to ResourceManager at hadoop0.hadoop.com/10.1.32.239:8032
16/06/07 08:49:54 WARN security.UserGroupInformation: PriviledgedActionException as:root (auth:SIMPLE) cause:org.apache.hadoop.security.AccessControlException: Permission denied: user=root, access=WRITE, inode="/user":hdfs:supergroup:drwxr-xr-x
at org.apache.hadoop.hdfs.server.namenode.DefaultAuthorizationProvider.checkFsPermission(DefaultAuthorizationProvider.java:281)
at org.apache.hadoop.hdfs.server.namenode.DefaultAuthorizationProvider.check(DefaultAuthorizationProvider.java:262)
at org.apache.hadoop.hdfs.server.namenode.DefaultAuthorizationProvider.check(DefaultAuthorizationProvider.java:242)
at org.apache.hadoop.hdfs.server.namenode.DefaultAuthorizationProvider.checkPermission(DefaultAuthorizationProvider.java:169)
at org.apache.hadoop.hdfs.server.namenode.FSPermissionChecker.checkPermission(FSPermissionChecker.java:152)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkPermission(FSNamesystem.java:6590)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkPermission(FSNamesystem.java:6572)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkAncestorAccess(FSNamesystem.java:6524)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.mkdirsInternal(FSNamesystem.java:4322)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.mkdirsInt(FSNamesystem.java:4292)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.mkdirs(FSNamesystem.java:4265)
at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.mkdirs(NameNodeRpcServer.java:867)
at org.apache.hadoop.hdfs.server.namenode.AuthorizationProviderProxyClientProtocol.mkdirs(AuthorizationProviderProxyClientProtocol.java:322)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.mkdirs(ClientNamenodeProtocolServerSideTranslatorPB.java:603)
at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:617)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:1073)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2086)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2082)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1693)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2080)

16/06/07 08:49:54 ERROR tool.ImportTool: Encountered IOException running import job: org.apache.hadoop.security.AccessControlException: Permission denied: user=root, access=WRITE, inode="/user":hdfs:supergroup:drwxr-xr-x
at org.apache.hadoop.hdfs.server.namenode.DefaultAuthorizationProvider.checkFsPermission(DefaultAuthorizationProvider.java:281)
at org.apache.hadoop.hdfs.server.namenode.DefaultAuthorizationProvider.check(DefaultAuthorizationProvider.java:262)
at org.apache.hadoop.hdfs.server.namenode.DefaultAuthorizationProvider.check(DefaultAuthorizationProvider.java:242)
at org.apache.hadoop.hdfs.server.namenode.DefaultAuthorizationProvider.checkPermission(DefaultAuthorizationProvider.java:169)
at org.apache.hadoop.hdfs.server.namenode.FSPermissionChecker.checkPermission(FSPermissionChecker.java:152)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkPermission(FSNamesystem.java:6590)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkPermission(FSNamesystem.java:6572)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkAncestorAccess(FSNamesystem.java:6524)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.mkdirsInternal(FSNamesystem.java:4322)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.mkdirsInt(FSNamesystem.java:4292)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.mkdirs(FSNamesystem.java:4265)
at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.mkdirs(NameNodeRpcServer.java:867)
at org.apache.hadoop.hdfs.server.namenode.AuthorizationProviderProxyClientProtocol.mkdirs(AuthorizationProviderProxyClientProtocol.java:322)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.mkdirs(ClientNamenodeProtocolServerSideTranslatorPB.java:603)
at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:617)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:1073)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2086)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2082)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1693)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2080)

Caused by: org.apache.hadoop.ipc.RemoteException(org.apache.hadoop.security.AccessControlException): Permission denied: user=root, access=WRITE, inode="/user":hdfs:supergroup:drwxr-xr-x
at org.apache.hadoop.hdfs.server.namenode.DefaultAuthorizationProvider.checkFsPermission(DefaultAuthorizationProvider.java:281)
at org.apache.hadoop.hdfs.server.namenode.DefaultAuthorizationProvider.check(DefaultAuthorizationProvider.java:262)
at org.apache.hadoop.hdfs.server.namenode.DefaultAuthorizationProvider.check(DefaultAuthorizationProvider.java:242)
at org.apache.hadoop.hdfs.server.namenode.DefaultAuthorizationProvider.checkPermission(DefaultAuthorizationProvider.java:169)
at org.apache.hadoop.hdfs.server.namenode.FSPermissionChecker.checkPermission(FSPermissionChecker.java:152)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkPermission(FSNamesystem.java:6590)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkPermission(FSNamesystem.java:6572)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkAncestorAccess(FSNamesystem.java:6524)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.mkdirsInternal(FSNamesystem.java:4322)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.mkdirsInt(FSNamesystem.java:4292)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.mkdirs(FSNamesystem.java:4265)
at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.mkdirs(NameNodeRpcServer.java:867)
at org.apache.hadoop.hdfs.server.namenode.AuthorizationProviderProxyClientProtocol.mkdirs(AuthorizationProviderProxyClientProtocol.java:322)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.mkdirs(ClientNamenodeProtocolServerSideTranslatorPB.java:603)
at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:617)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:1073)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2086)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2082)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1693)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2080)

at org.apache.hadoop.ipc.Client.call(Client.java:1471)
at org.apache.hadoop.ipc.Client.call(Client.java:1408)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:230)
at com.sun.proxy.$Proxy15.mkdirs(Unknown Source)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolTranslatorPB.mkdirs(ClientNamenodeProtocolTranslatorPB.java:544)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:256)
at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:104)
at com.sun.proxy.$Proxy16.mkdirs(Unknown Source)
at org.apache.hadoop.hdfs.DFSClient.primitiveMkdir(DFSClient.java:3082)
... 28 more

解决：
因为在使用sqoop导入HDFS文件时，使用的是root用户，没有写hdfs文件的权限。
CDH安装时创建了hdfs用户，应使用hdfs用户登录，再时行sqoop导入
[root@hadoop1 ~]# su - hdfs
[hdfs@hadoop1 ~]$ pwd
/var/lib/hadoop-hdfs
[hdfs@hadoop1 ~]$ ls
t1.java

问题3：其它hadoop节点不连接MySql "is not allowed to connect to this MySQL server"

[hdfs@hadoop1 ~]$ sqoop import --connect jdbc:mysql://10.1.32.8:3306/test --username sqoop --password sqoop --table t1 -m 1
16/06/07 08:51:52 INFO sqoop.Sqoop: Running Sqoop version: 1.4.6-cdh5.7.0
......
16/06/07 08:52:00 INFO mapreduce.Job: The url to track the job: http://hadoop0.hadoop.com:8088/proxy/application_1464249387420_0001/ 16/06/07 08:52:00 INFO mapreduce.Job: Running job: job_1464249387420_0001
16/06/07 08:52:08 INFO mapreduce.Job: Job job_1464249387420_0001 running in uber mode : false
16/06/07 08:52:08 INFO mapreduce.Job:  map 0% reduce 0%
16/06/07 08:52:14 INFO mapreduce.Job: Task Id : attempt_1464249387420_0001_m_000000_0, Status : FAILED
Error: java.lang.RuntimeException: java.lang.RuntimeException: java.sql.SQLException: null,  message from server: "Host 'hadoop4.hadoop.com' is not allowed to connect to this MySQL server"
at org.apache.sqoop.mapreduce.db.DBInputFormat.setConf(DBInputFormat.java:167)
at org.apache.hadoop.util.ReflectionUtils.setConf(ReflectionUtils.java:73)
at org.apache.hadoop.util.ReflectionUtils.newInstance(ReflectionUtils.java:133)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:749)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:164)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1693)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:158)
Caused by: java.lang.RuntimeException: java.sql.SQLException: null,  message from server: "Host 'hadoop4.hadoop.com' is not allowed to connect to this MySQL server"
at org.apache.sqoop.mapreduce.db.DBInputFormat.getConnection(DBInputFormat.java:220)
at org.apache.sqoop.mapreduce.db.DBInputFormat.setConf(DBInputFormat.java:165)
... 9 more
Caused by: java.sql.SQLException: null,  message from server: "Host 'hadoop4.hadoop.com' is not allowed to connect to this MySQL server"

解决：
这是因为客户端没有访问mysql的权限，修改sqoop用户的客户端访问权限。
--登录mysql服务器
[root@hadoop2 ~]# mysql -uroot -proot
mysql> grant all privileges on *.* to 'sqoop'@'%' identified by 'sqoop' with grant option;
Query OK, 0 rows affected (0.00 sec)