To start Oracle Enterprise Manager Database Express (EM Express) for a multitenant container database (CDB), use the EM Express URL provided by Database Configuration Assistant (DBCA) when DBCA configured your CDB, as described in "Installing Oracle Database Software." That URL includes the HTTPS port number for the CDB.
If you do not know the HTTPS port number for the CDB, go to the root and issue the SQL statement that returns the port that is configured for EM Express:
alter session set container=CDB$ROOT; select dbms_xdb_config.gethttpsport() from dual;
If a port number is not returned by this statement, then you must manually configure an HTTPS port for this CDB, as described in "Configuring the HTTPS Port for EM Express."
When connected to the root, EM Express displays data and enables actions that apply to the entire CDB.
See Also:
Managing PDBs with EM Express for more information about using EM Express to manage the pluggable databases (PDBs) in a CDB
Oracle Database Administrator's Guide for information about switching to a container using the ALTER SESSION statement
Oracle Database PL/SQL Packages and Types Reference for more information on the gethttpsport procedure