Hive配置中的一些错误

一、NameNode处于安全模式

Exception in thread "main" org.apache.hadoop.ipc.RemoteException( org.apache.hadoop.hdfs.server.namenode.SafeModeException): Cannot delete /tmp/hadoop- yarn/staging/hadoop/.staging/job_1490689337938_0001. Name node is in safe mode.

1、NameNode发现集群中DataNode丢失达到一定比例（0.01%）时会进入安全模式，此时只允许查看数据不允许对数据进行任何操作。

退出安全模式，命令如下

sudo bin/hadoop dfsadmin -safemode leave

二、IO报错

Failed with exception java.io.IOException:java.lang.IllegalArgumentException

添加属性 system:java.io.tmpdir：

<property> <name>system:java.io.tmpdir</name> <value>/opt/modules/hive/iotmp</value> ##注意这里路径为本机上的绝对路径 <description/> </property>

三、未导jar包或不匹配

Error creating transactional connection factory

需要下和mysql版本一致的jar包mysql-connector-java-（mysql版本号）.jar

四、建表失败（字符集错误）

Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask. MetaException(message:For direct MetaStore DB connections, FAILED: Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.DDLTask.

mysql>drop database metastore; mysql>create database metastore; mysql>alter database metastorecharacter set latin1;

vi /etc/my.cnf 末尾加上default-character-set=utf8 五、文件上传失败

LOAD DATA LOCAL INPATH '/opt/datas/wc.data' INTO TABLE db_hive.tb_word; Failed with exception Unable to move source hdfs Execution Error, return code 1 from org.apache.hadoop.hive.ql.exec.MoveTask

缺少jar包

cp share/hadoop/tools/lib/hadoop-distcp-2.7.3.jar ../hive/lib/hadoop-distcp-2.7.3.jar

配置 /opt/modules/hive/conf/hive-site.xml hive.insert.into.multilevel.dirs，默认是false 作用就是限制SQL中指定存放结果文件不存在的目录的深度不能大于1.

<property> <name>hive.insert.into.multilevel.dirs</name> <value>true</value> </property>

六、mysql 忘记root密码

（1）进入Mysql的配置文件：vi /etc/my.cnf （2）在配置文件的末尾加上： skip-grant-tables， （3）重启Mysql，然后直接mysql -u root -p直接登入。

mysql>update user set password=password('123456') where user='root'; mysql>flush privileges;

GRANT ALL PRIVILEGES ON . TO ‘root’@’%’ IDENTIFIED BY ‘123456’ WITH GRANT OPTION;