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报错
使用连接测试命令：
sqoop list-databases --connect jdbc:mysql://master:3306/ --username bee -P
报如下错误：
18/12/02 20:11:44 ERROR manager.CatalogQueryManager: Failed to list databases
com.mysql.cj.jdbc.exceptions.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 com.mysql.cj.jdbc.exceptions.SQLError.createCommunicationsException(SQLError.java:174)
at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:64)
at com.mysql.cj.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:835)
at com.mysql.cj.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:455)
at com.mysql.cj.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:240)
at com.mysql.cj.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:207)
at java.sql.DriverManager.getConnection(DriverManager.java:664)
at java.sql.DriverManager.getConnection(DriverManager.java:247)
at org.apache.sqoop.manager.SqlManager.makeConnection(SqlManager.java:904)
at org.apache.sqoop.manager.GenericJdbcManager.getConnection(GenericJdbcManager.java:59)
at org.apache.sqoop.manager.CatalogQueryManager.listDatabases(CatalogQueryManager.java:57)
at org.apache.sqoop.tool.ListDatabasesTool.run(ListDatabasesTool.java:49)
at org.apache.sqoop.Sqoop.run(Sqoop.java:147)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
at org.apache.sqoop.Sqoop.runSqoop(Sqoop.java:183)
at org.apache.sqoop.Sqoop.runTool(Sqoop.java:234)
at org.apache.sqoop.Sqoop.runTool(Sqoop.java:243)
at org.apache.sqoop.Sqoop.main(Sqoop.java:252)
Caused by: com.mysql.cj.exceptions.CJCommunicationsException: Communications link failure
解决办法
修改 my.cnf 配置文件：
vim /etc/mysql/my.cnf，如果没有则添加
[mysqld]
bind-address=0.0.0.0
再次连接成功：
