搞了一把手动创建oralce EM, 记录创建步骤如下：

1. 运行下面的命令创建EM repository
emca -config dbcontrol db -repos create

2. 创建过程中遇到两个错误
a. 配置: ORA-28000: 帐户已被锁定
oracle.sysman.assistants.util.sqlEngine.SQLFatalErrorException: ORA-28000: 帐户已被锁定
at oracle.sysman.assistants.util.sqlEngine.SQLEngine.executeImpl(SQLEngine.java:1467)
at oracle.sysman.assistants.util.sqlEngine.SQLEngine.connect(SQLEngine.java:814)
at oracle.sysman.assistants.util.sqlEngine.SQLEngine.connect(SQLEngine.java:777)
at oracle.sysman.emcp.util.GeneralUtil.initSQLEngine(GeneralUtil.java:359)
at oracle.sysman.emcp.DatabaseChecks.validateUserCredentials(DatabaseChecks.java:986)
at oracle.sysman.emcp.ParamsManager.validatePassword(ParamsManager.java:2694)
at oracle.sysman.emcp.EMConfigAssistant.promptForData(EMConfigAssistant.java:583)
at oracle.sysman.emcp.EMConfigAssistant.promptForParams(EMConfigAssistant.java:2231)
at oracle.sysman.emcp.EMConfigAssistant.displayWarnsAndPromptParams(EMConfigAssistant.java:2257)
at oracle.sysman.emcp.EMConfigAssistant.getDisplayAndPromptWarnsParms(EMConfigAssistant.java:2284)
at oracle.sysman.emcp.EMConfigAssistant.performConfiguration(EMConfigAssistant.java:928)
at oracle.sysman.emcp.EMConfigAssistant.statusMain(EMConfigAssistant.java:463)
at oracle.sysman.emcp.EMConfigAssistant.main(EMConfigAssistant.java:412)

3. 执行以下步骤解决了遇到的问题
a. drop user sysman cascade;
b. drop role MGMT_USER;
c. drop user MGMT_VIEW cascade;
d. drop public synonym MGMT_TARGET_BLACKOUTS;
e. drop public synonym SETEMVIEWUSERCONTEXT;

Note: Make sure sysman and MGMT_VIEW are unlock status. Otherwise, use command below to unlock them

alter user sysman account unlock;
alter user mgmt_view account unlock;

4. 重新执行创建命令, EM创建成功
emca -config dbcontrol db -repos create

PS: 贴上关于sysman和mgmt_user的说明

SYSMAN:
By default during the installation of Oracle Enterprise Manager, one Super Administrator account is created with
the user name of SYSMAN. The SYSMAN account should be used to perform infrequent system-wide, global configuration
tasks such as setting up the environment. Other administrator accounts can be created for daily administration work. The SYSMAN account is:

1. Owner of the Management Repository schema
2. Default Enterprise Manager Super Administrator
3. User name used to log in to Enterprise Manager the first time

MGMT_VIEW:
An account used by Oracle Enterprise Manager Database Control ( Default password: Randomly generated )