1、重新配置OEM时，一定要首先配置监听，并启动监听。
2、保证监听里的host是静态IP地址或者主机名；
3、在日志文件中，出现以下错误：ORA-20001: SYSMAN already exists..
ORA-06512:在line 17，运行以下命令之后：
drop user sysman cascade;
drop role MGMT_USER;
DROP USER MGMT_VIEW CASCADE;
drop public synonym MGMT_TARGET_BLACKOUTS;
drop public synonym SETEMVIEWUSERCONTEXT;
4、运行命令。重建OEM：emca -config
dbcontrol db-repos recreate
5、如果出现以下错误，则首先检查监听中host是否是静态IP或者主机名，然后再按照下边红色的步骤操作。
保护Database Control时出错, Database
Control已在非安全模式下启动。要保护Database Control,请执行以下命令:
1)将环境变量ORACLE_SID设置为orcl
2) D:\oracle\product\10.2.0\db_1\bin\emctl.bat
stop dbconsole
3) D:\oracle\product\10.2.0\db_1\bin\emctl.bat
config emkey -repos -sysman_pwd < SYSMAN用户的口令>
4) D:\oracle\product\10.2.0\db_1\bin\emctl.bat
secure dbconsole -sysman_pwd < SYSMAN用户的口令>
5) D:\oracle\product\10.2.0\db_1\bin\emctl.bat
start dbconsole
要保护EM密钥,请运行D:\oracle\product\10.2.0\db_1\bin\emctl.bat config emkey-remove_from_repos -sysman_pwd < SYSMAN用户的口令>
C:\Windows\system32>set ORACLE_SID=orcl
C:\Windows\system32>D:\oracle\product\10.2.0\db_1\bin\emctl.bat
config emkey -repos -sysman_pwd windows host thinkpad sid orcl
Oracle
Enterprise Manager 10g Database Control Release 10.2.0.4.0
Copyright
(c) 1996, 2007 Oracle Corporation.All
rights reserved.
Invalid
Password
caught Exception java.sql.SQLException: Io异常: The Network Adapter could not establish the connection
注释：监听主机名不是静态Ip或者主机名
C:\Windows\system32>D:\oracle\product\10.2.0\db_1\bin\emctl.bat config emkey -repos
-sysman_pwd windows host thinkpad sid orcl
Oracle
Enterprise Manager 10g Database Control Release 10.2.0.4.0
Copyright
(c) 1996, 2007 Oracle Corporation.All
rights reserved.
The Em
Key has been configured successfully.
C:\Windows\system32>
D:\oracle\product\10.2.0\db_1\bin\emctl.bat secure
dbconsole -sysman_pwd windows host thinkpad sid orcl
Oracle
Enterprise Manager 10g Database Control Release 10.2.0.4.0
Copyright
(c) 1996, 2007 Oracle Corporation.All
rights reserved.
C:\Windows\system32>emctl start dbconsole
Normal
0
7.8 磅
0
2
false
false
false
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