source database

SQL> select name,open_mode,version from v$database,v$instance;

NAME      OPEN_MODE            VERSION
--------- -------------------- -----------------
ORCL12C   READ WRITE           12.1.0.2.0

Listener info. We already have 19c db avaialble on the system so we can see 19c listener

[oracle@ol7-n1 ~]$ ps -ef|grep tns
root        16     2  0 08:38 ?        00:00:00 [netns]
oracle   10077     1  0 09:11 ?        00:00:00 /u01/app/oracle/19c_db_sw/bin/tnslsnr LISTENER -inherit
oracle   11281     1  0 09:22 ?        00:00:00 /u01/app/oracle/product/12.1.0/dbhome_1/bin/tnslsnr LISTENER12C -inherit
oracle   16007 13438  0 10:02 pts/0    00:00:00 grep --color=auto tns


[root@ol7-n1 oracle]# ps -ef|grep pmon
oracle    9462     1  0 09:09 ?        00:00:00 ora_pmon_orcl19c
oracle   12866     1  0 09:38 ?        00:00:00 ora_pmon_orcl12c
root     13393  2617  0 09:42 pts/0    00:00:00 grep --color=auto pmon

set the env to 19c ORACLE_HOME and invloke dbua

[oracle@ol7-n1 bin]$ pwd
/u01/app/oracle/19c_db_sw/bin
[oracle@ol7-n1 bin]$ which dbua
/u01/app/oracle/19c_db_sw/bin/dbua

[oracle@ol7-n1 bin]$ ./dbua
Logs directory:  /u01/app/oracle/cfgtoollogs/dbua/upgrade2021-01-27_09-47-08AM

select the database you want to upgarde to 19c – orcl12c

provide sysdba credentials

let the pre upgrade checks run

see the recommendations

as a pre upgrade recommendation – gather database stats and click next

SQL> select name,open_mode,version from v$database,v$instance;

NAME      OPEN_MODE            VERSION
--------- -------------------- -----------------
ORCL12C   READ WRITE           12.1.0.2.0

SQL> EXEC DBMS_STATS.gather_database_stats;

PL/SQL procedure successfully completed.

select the required checkbox as per requirement

i am selecing the option to create flashback restorepoint

currently no restore point

SQL> select * from v$restore_point;

no rows selected

select the already avaialble 19c listener

choosee em express option if you wish

verify the details in summary page

check database status and gather stats as post upgrade step

SQL> select name,open_mode,version from v$database,v$instance;

NAME      OPEN_MODE            VERSION
--------- -------------------- -----------------
ORCL12C   READ WRITE           19.0.0.0.0

SQL> EXEC DBMS_STATS.gather_database_stats;

PL/SQL procedure successfully completed.

we can see now guaranteed restore point is avaialable in database which can be used if you want to rollback

SQL>  select SCN,TIME,NAME,GUARANTEE_FLASHBACK_DATABASE from v$restore_point;

       SCN TIME                                                                        NAME                                     GUA
---------- --------------------------------------------------------------------------- ---------------------------------------- ---
    343253 27-JAN-21 09.56.41.000000000 AM                                             GRP_1611721601338                        YES

check listener status

[oracle@ol7-n1 ~]$ lsnrctl status

LSNRCTL for Linux: Version 19.0.0.0.0 - Production on 27-JAN-2021 10:44:06

Copyright (c) 1991, 2019, Oracle.  All rights reserved.

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=ol7-n1.localdomain)(PORT=1521)))
STATUS of the LISTENER
------------------------
Alias                     LISTENER
Version                   TNSLSNR for Linux: Version 19.0.0.0.0 - Production
Start Date                27-JAN-2021 09:11:30
Uptime                    0 days 1 hr. 32 min. 37 sec
Trace Level               off
Security                  ON: Local OS Authentication
SNMP                      OFF
Listener Parameter File   /u01/app/oracle/19c_db_sw/network/admin/listener.ora
Listener Log File         /u01/app/oracle/diag/tnslsnr/ol7-n1/listener/alert/log.xml
Listening Endpoints Summary...
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=ol7-n1.localdomain)(PORT=1521)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcps)(HOST=ol7-n1.localdomain)(PORT=5500))(Security=(my_wallet_directory=/u01/app/oracle/admin/orcl19c/xdb_wallet))(Presentation=HTTP)(Session=RAW))
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcps)(HOST=ol7-n1.localdomain)(PORT=5501))(Security=(my_wallet_directory=/u01/app/oracle/admin/orcl12c/xdb_wallet))(Presentation=HTTP)(Session=RAW))
Services Summary...
Service "orcl12c.localdomain" has 1 instance(s).
  Instance "orcl12c", status READY, has 1 handler(s) for this service...
Service "orcl12cXDB.localdomain" has 1 instance(s).
  Instance "orcl12c", status READY, has 1 handler(s) for this service...
Service "orcl19c.localdomain" has 1 instance(s).
  Instance "orcl19c", status READY, has 1 handler(s) for this service...
Service "orcl19cXDB.localdomain" has 1 instance(s).
  Instance "orcl19c", status READY, has 1 handler(s) for this service...
The command completed successfully