How to enable Oracle Enterprise Manager Express 12c

Oracle Enterprise Manager Express is a Web-based interface for managing an Oracle database 12c. It enables users to perform basic administrative tasks such as managing users, managing database initialization parameters, memory or storage. You can also view performance and SQL Tuning Advisor information, check status information about your database and pluggable databases.

In Oracle Database 12c Release 1, the concept of multi-tenant environment has been introduced. The multi-tenant architecture enables an Oracle database to function as a multi-tenant container database (CDB) that includes zero, one, or many customer-created pluggable databases (PDBs).

A CDB includes the following components:

Root named CDB$ROOT, stores Oracle-supplied metadata and common users. An example of metadata is the source code for Oracle-supplied PL/SQL packages. A common user is a database user known in every container.

A PDB appears to users and applications as if it were a non-CDB. For example, a PDB can contain the data and code required to support a specific application (e.g., APEX).

Each of these components is called a container. Therefore, the root is a container, the seed is a container, and each PDB is a container.

In this tutorial we will show two different types of configurations of Enterprise Manager Express one for CDB and the second for PDBs only. Imagine yourself as a dba who has full access to non-CDB/CDB/PDB, OEM Express 12c will allow you to manage CDB and all PDB containers from one central console. On the other hand you would like to allow regular users to login to OEM Express 12c as well, but grant them access to their PDBs only.

In our demo environment we have the following containers created:

CDB: ZIONDB,

PDBs: PDB01_OEM12c, PDB02_SOA12c

Configuring OEM Express for CDB (HTTPs & HTTP)

1. Open a terminal window, execute the oraenv command to set the environment variables and connect to the multi-tenant container database (in our example ZIONDB) Check if the database is a CDB database and it is open.

[oracle@zeus ~]$ . oraenv
ORACLE_SID = [oracle] ? ZIONDB


[oracle@zeus ~]$ sqlplus / as sysdba
Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 64bit 
...

SQL> select name, cdb, con_id from v$database;

NAME      CDB     CON_ID
--------- --- ----------
ZIONDB    YES          0

SQL> select instance_name, status, con_id from v$instance;

INSTANCE_NAME    STATUS           CON_ID
---------------- ------------ ----------
ZIONDB           OPEN                  0

2. Verify that the DISPATCHERS parameter in the initialization parameter file includes the PROTOCOL=TCP attribute.

SQL> show parameter dispatchers

NAME               TYPE        VALUE
------------------ ----------- ------------------------------
dispatchers        string      (PROTOCOL=TCP) (SERVICE=ZIONDBXDB)
max_dispatchers    integer

3. Execute the DBMS_XDB.setHTTPSPort procedure to set the HTTPS port 5500 and the DBMS_XDB.setHTTPPort procedure to set the HTTP port 5510 for EM Express

SQL> exec DBMS_XDB_CONFIG.SETHTTPSPORT(5500);

SQL> exec DBMS_XDB_CONFIG.SETHTTPPORT(5510);

PL/SQL procedure successfully completed.

5. Login to Database EM Express Home Page.

https://<IP:Hostname>:5500/em and http://<IP:Hostname>:5510/em

Note: Now we have the privileges to manage CDB and PDBs containers

Configuring OEM Express for PDB PDB01_OEM12c

We are configuring EM Express for PDB01_OEM12c container to run on ports: HTTPs 5501 and HTTP 5511.

1. Display all pluggable databases and their status

SQL> select NAME, OPEN_MODE from v$pdbs;

NAME                           OPEN_MODE
------------------------------ ----------
PDB$SEED                       READ ONLY
PDB01_OEM12C                   READ WRITE
PDB02_SOA12C                   READ WRITE

2. Alter the session and set container as PDB01_OEM12C

SQL> alter session set container=PDB01_OEM12C;

Session altered.

3. Execute the DBMS_XDB.setHTTPSPort procedure to set the HTTPS port 5501 and the DBMS_XDB.setHTTPPort procedure to set the HTTP port 5511 for EM Express

SQL> exec DBMS_XDB_CONFIG.SETHTTPSPORT(5501);

SQL> exec DBMS_XDB_CONFIG.SETHTTPPORT(5511);

PL/SQL procedure successfully completed.

5. Login to Database EM Express home page.

https://<IP:Hostname>:5501/em and http://<IP:Hostname>:5511/em

Note that you have privileges to managed only PDB PDB01_OEM12C

Repeat recent steps from 2 to 5 to configure EM Express for more PDBs.

Checking OEM Express port for CDB or PDB

Alter session to CDB or PDB container and execute the SQL statement that returns the port that is configured for EM Express

SQL> select DBMS_XDB_CONFIG.GETHTTPPORT() from dual;

DBMS_XDB_CONFIG.GETHTTPPORT()
-----------------------------
                         5511

SQL> select DBMS_XDB_CONFIG.GETHTTPSPORT() from dual;

DBMS_XDB_CONFIG.GETHTTPSPORT()
------------------------------
                          5501

If returned port number is 0, it means that EM Express is not configured for that particular container.

Cheers!!