https://database-hostname:portnumber/em/查non-CDB的端口号
select dbms_xdb_config.gethttpsport() from dual;
查看CDB的https端口号
alter session set container=CDB$ROOT;
select dbms_xdb_config.gethttpsport() from dual;查看PDB的https端口号
alter session set container=PDB1;
select dbms_xdb_config.gethttpsport() from dual;监听必须启动
非默认监听端口
local_listener=inst1
inst1必须在tnsnames.ora里面有，例如
inst1= (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=host_name)(PORT=1234))
(CONNECT_DATA=(SERVICE_NAME=service_name)(SERVER=DEDICATED)))3.允许tcp调度员通过下面的配置进入到init.ora去管理EM
dispatchers="(PROTOCOL=TCP) (SERVICE=<sid>XDB)"4.重启数据库，让改变在init.ora文件生效
5.使用DBMS_XDB_CONFIG.SETHTTPSPORT设置em的https端口，
将会更新xdbconfig.xml里的https端口
(不管设置成什么端口号，都不能与本服务器其他服务端口冲突)
设置non-CDB https端口
conn sys / as sysdba;
sql>exec DBMS_XDB_CONFIG.SETHTTPSPORT(5500);设置CDB https端口
conn sys / as sysdba;
sql>alter session set container=CDB$ROOT;
sql>exec DBMS_XDB_CONFIG.SETHTTPSPORT(5501);设置PDB https端口
conn sys / as sysdba;
sql>alter session set container=PDB1;
sql>exec DBMS_XDB_CONFIG.SETHTTPSPORT(5502);使用下面的命令确认注册在监听上的端口
$lsnrctl status| grep -i 5502
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcps)(HOST=hostname.example.com)(PORT=5502)
)(Security=(my_wallet_directory=/$ORACLE_BASE/admin/sid/xdb_wallet))
(Presentation=HTTP)(Session=RAW))
访问em，根据端口号区别要连接到的是non-CDB,CDB,PDB
https://database-hostname:portnumber/em/
登录进去的用户是做为dba权限的
文档链接：
http://docs.oracle.com/database/121/ADMQS/GUID-EB851101-07BE-4038-BB9D-06E01CC7F5D5.htm#ADMQS032
