启动 cloudera-scm-server服务 出现：Error creating bean with name 'entityManagerFactoryBean':

1.这个错误是启动 cloudera-scm-server服务出现的
2. 先看一下报错的内容

2017-04-29 18:45:25,476 INFO main:org.hibernate.service.jdbc.connections.internal.C3P0ConnectionProvider: HHH010002: C3P0 using driver: com.mysql.jdbc.Driver at URL: jdbc:mysql://null/null?useUnicode=true&characterEncoding=UTF-82017-04-29 18:45:25,477 INFO main:org.hibernate.service.jdbc.connections.internal.C3P0ConnectionProvider: HHH000046: Connection properties: {user=, password=****, autocommit=true, release_mode=auto}2017-04-29 18:45:25,477 INFO main:org.hibernate.service.jdbc.connections.internal.C3P0ConnectionProvider: HHH000006: Autocommit mode: true2017-04-29 18:45:25,478 INFO main:org.springframework.beans.factory.support.DefaultListableBeanFactory: Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@46cf209b: defining beans [commandLineConfigurationBean,entityManagerFactoryBean,com.cloudera.server.cmf.TrialState,com.cloudera.server.cmf.TrialManager,com.cloudera.cmf.crypto.LicenseLoader]; root of factory hierarchy2017-04-29 18:45:25,479 ERROR main:com.cloudera.server.cmf.Main: Server failed.org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.cloudera.server.cmf.TrialState': Cannot resolve reference to bean 'entityManagerFactoryBean' while setting constructor argument; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactoryBean': FactoryBean threw exception on object creation; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: cmf.server] Unable to build EntityManagerFactory    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:328)    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:106)    at org.springframework.beans.factory.support.ConstructorResolver.resolveConstructorArguments(ConstructorResolver.java:616)    at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:148)

2.分析从日志中我们可以看到应该是数据库的问题，因为很明显有一行日志用户名和密码都是空。于是去官网看了下。好像是启动要用到另外的数据库，有三种，我选择了mysql，如果不会在linux下安装mysql请参考http://blog.csdn.net/qq_22222499/article/details/70992925。官网参考地址http://www.cloudera.com/documentation/manager/5-1-x/Cloudera-Manager-Installation-Guide/cm5ig_installing_configuring_dbs.html#cmig_topic_5_2_unique_1。
3.安装好后，执行下列命令./scm_prepare_database.sh database-type [options] database-name username password 看了官网应该知道这个在个文件在哪里。我们在数据库中应该建立一个数据库供cloudera使用。
4.可能还会出现情况，就是JDBC driver cannot be found，这时把jar包复现到 /usr/share/cmf/lib 下就行了。
5.重启cloudera-scm-server服务。
6.等待1分钟，访问7180端口，应该就不会出问题了。