You can use Oracle Enterprise Manager Database Express (EM Express) to manage a non-CDB, a multitenant container database (CDB), or a pluggable database (PDB). For each non-CDB, CDB, or PDB that you want to manage using EM Express on a given host, a unique HTTPS port must be configured. A different port must be configured for each container in a CDB that you want to manage using EM Express.
Note:
You can use EM Express to manage a CDB, and all the PDBs in the CDB except for the seed PDB.
Usually the HTTPS port for a non-CDB, CDB, or PDB is provided by DBCA when it configures your non-CDB, CDB, or PDB.
You must know the HTTPS port for a non-CDB, CDB, or PDB to manage the database using EM Express.
When you specify the EM Express URL in your web browser, enter your database hostname instead of 'localhost.'
In other words, enter the EM Express URL in this format to start EM Express:
https://database-hostname:portnumber/em/
For example:
https://mydbhost.example.com:5500/em/
When EM Express prompts you for your username and password, log in as a user with DBA privilege (such as SYS or SYSTEM).
The “SYS and SYSTEM Users” topic provides information about the recommended alternative to using the SYSTEM account for day-to-day administrative tasks.
Note:
The first time you enter the URL for EM Express in your web browser, your browser may display warning messages.
EM Express is a servlet built on top of Oracle XML DB. The Oracle XML DB default wallet has a self-signed certificate, and some existing browsers consider self-signed certificates as untrusted because they are not signed by a trusted CA (certificate authority). However, the self-signed certificate is still secure, as it ensures that the traffic is encrypted between the Oracle XML DB server and the client (browser).
Therefore, enter a security exception for the EM Express URL in your web browser.