Oracle12c环境中，EM不需要单独安装配置了，创建数据库的时候勾选EM express即可。登陆方式也发生了变化，原来的http://localhost:1158/em或者https://localhost:1158/em登陆总是会遇到问题，解决方法需要使用到XDB，需要手动设置端口。

查看监听

[oracle@localhost admin]$ lsnrctl status

LSNRCTL for Linux: Version 12.2.0.1.0 - Production on 24-DEC-2019 17:05:57

Copyright (c) 1991, 2016, Oracle.  All rights reserved.

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=1521)))

STATUS of the LISTENER

------------------------

Alias                     LISTENER

Version                   TNSLSNR for Linux: Version 12.2.0.1.0 - Production

Start Date                28-AUG-2018 13:07:15

Uptime                    483 days 3 hr. 58 min. 44 sec

Trace Level               off

Security                  ON: Local OS Authentication

SNMP                      OFF

Listener Parameter File   /u01/app/product/12.2.0/db_1/network/admin/listener.ora

Listener Log File         /u01/app/diag/tnslsnr/localhost/listener/alert/log.xml

Listening Endpoints Summary...

(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=localhost)(PORT=1521)))

(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=localhost)(PORT=5500))(Presentation=HTTP)(Session=RAW))

Services Summary...

Service "orcl" has 1 instance(s).

Instance "orcl", status READY, has 1 handler(s) for this service...

Service "orclXDB" has 1 instance(s).

Instance "orcl", status READY, has 1 handler(s) for this service...

The command completed successfully

数据库安装配置好em后，默认端口号为5500；

SQL> select dbms_xdb_config.gethttpsport() from dual;

DBMS_XDB_CONFIG.GETHTTPSPORT()

------------------------------

5500