问题 - 将数据从 mysql 导入到 HDFS

Question

我正在尝试将 table "employee" 从 MySQL（安装在我的笔记本电脑上）导入到 HDFS（也安装在我笔记本电脑上的虚拟机上）

我也已授予 MySQL 所有权限..成功使用以下命令

将 . 上的所有权限授予 root@192.168.56.1 IDENTIFIED BY 'root' WITH GRANT OPTION;

可能是什么问题..

请帮忙!!

出现以下错误

[edureka@localhost sqoop-1.4.4]$ bin/sqoop import --connect jdbc:mysql://192.168.56.1/test --table employee --username root -P --target-dir /out/10sep/sq1 -m 1Warning: /usr/lib/hcatalog does not exist! HCatalog jobs will fail.
Please set $HCAT_HOME to the root of your HCatalog installation.
Enter password: 
15/09/15 13:40:31 INFO manager.MySQLManager: Preparing to use a MySQL streaming resultset.
15/09/15 13:40:31 INFO tool.CodeGenTool: Beginning code generation
15/09/15 13:41:34 ERROR manager.SqlManager: Error executing statement: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
    at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1121)
    at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:357)
    at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2482)
    at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2519)
    at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2304)
    at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:834)
    at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
    at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
    at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:416)
    at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:346)
    at java.sql.DriverManager.getConnection(DriverManager.java:571)
    at java.sql.DriverManager.getConnection(DriverManager.java:215)
    at org.apache.sqoop.manager.SqlManager.makeConnection(SqlManager.java:801)
    at org.apache.sqoop.manager.GenericJdbcManager.getConnection(GenericJdbcManager.java:52)
    at org.apache.sqoop.manager.SqlManager.execute(SqlManager.java:660)
    at org.apache.sqoop.manager.SqlManager.execute(SqlManager.java:683)
    at org.apache.sqoop.manager.SqlManager.getColumnTypesForRawQuery(SqlManager.java:240)
    at org.apache.sqoop.manager.SqlManager.getColumnTypes(SqlManager.java:223)
    at org.apache.sqoop.manager.ConnManager.getColumnTypes(ConnManager.java:347)
    at org.apache.sqoop.orm.ClassWriter.getColumnTypes(ClassWriter.java:1277)
    at org.apache.sqoop.orm.ClassWriter.generate(ClassWriter.java:1089)
    at org.apache.sqoop.tool.CodeGenTool.generateORM(CodeGenTool.java:96)
    at org.apache.sqoop.tool.ImportTool.importTable(ImportTool.java:396)
    at org.apache.sqoop.tool.ImportTool.run(ImportTool.java:502)
    at org.apache.sqoop.Sqoop.run(Sqoop.java:145)
    at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
    at org.apache.sqoop.Sqoop.runSqoop(Sqoop.java:181)
    at org.apache.sqoop.Sqoop.runTool(Sqoop.java:220)
    at org.apache.sqoop.Sqoop.runTool(Sqoop.java:229)
    at org.apache.sqoop.Sqoop.main(Sqoop.java:238)
Caused by: java.net.ConnectException: Connection timed out
    at java.net.PlainSocketImpl.socketConnect(Native Method)
    at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339)
    at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200)
    at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182)
    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
    at java.net.Socket.connect(Socket.java:579)
    at java.net.Socket.connect(Socket.java:528)
    at java.net.Socket.<init>(Socket.java:425)
    at java.net.Socket.<init>(Socket.java:241)
    at com.mysql.jdbc.StandardSocketFactory.connect(StandardSocketFactory.java:259)
    at com.mysql.jdbc.MysqlIO.<init>(MysqlIO.java:307)
    ... 32 more
15/09/15 13:41:34 ERROR tool.ImportTool: Encountered IOException running import job: java.io.IOException: No columns to generate for ClassWriter
    at org.apache.sqoop.orm.ClassWriter.generate(ClassWriter.java:1095)
    at org.apache.sqoop.tool.CodeGenTool.generateORM(CodeGenTool.java:96)
    at org.apache.sqoop.tool.ImportTool.importTable(ImportTool.java:396)
    at org.apache.sqoop.tool.ImportTool.run(ImportTool.java:502)
    at org.apache.sqoop.Sqoop.run(Sqoop.java:145)
    at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
    at org.apache.sqoop.Sqoop.runSqoop(Sqoop.java:181)
    at org.apache.sqoop.Sqoop.runTool(Sqoop.java:220)
    at org.apache.sqoop.Sqoop.runTool(Sqoop.java:229)
    at org.apache.sqoop.Sqoop.main(Sqoop.java:238)

Answer 1

SQOOP 执行 MapReduce 作业以并行工作。问题是：您所有的 hadoop 节点都能够与 MySQL 通信吗？在您的示例中，您只向一台主机授予对数据库的访问权限。您的 hadoop "cluster" 是独立实例吗？

问题 - 将数据从 mysql 导入到 HDFS

Issue - Importing data from mysql to HDFS

mysql

import

hadoop

sqoop