Here’s a cool way of upgrading your database in OCI to Oracle Database 23c. I will move my PDB to a new Base Database System using refreshable clone PDBs and AutoUpgrade.

The benefit of using this approach is:

• Shorter downtime than an in-place upgrade.
• A brand-new Base Database System, which means the operating system and Oracle Grid Infrastructure is already on a newer version.

My Environment

I have one PDB that I want to upgrade. It’s called SALES.

Source

• Base Database System on 19.20.0
• Name DBS19

Target

• Base Database System on 23.3.0
• Name DBS23

How To

Prepare AutoUpgrade

• I must use a version of AutoUpgrade that supports upgrades to Oracle Database 23c, and I must have AutoUpgrade on the source and target system.

  $ java -jar autoupgrade.jar -version
  

• At the time of writing, the latest version of AutoUpgrade on My Oracle Support does not support 23 as a target release. Instead, I copy AutoUpgrade from the target Oracle Home (on DBS23) to the source Oracle Home (on DBS19). This version allows upgrades to Oracle Database 23c.
• I create an AutoUpgrade config file, named sales.cfg, which I store on both servers:

  global.autoupg_log_dir=/u01/app/oracle/cfgtoollogs/autoupgrade
  global.keystore=/u01/app/oracle/cfgtoollogs/keystore
  upg1.source_home=/u01/app/oracle/product/19.0.0.0/dbhome_1
  upg1.target_home=/u01/app/oracle/product/23.0.0.0/dbhome_1
  upg1.sid=CDB19
  upg1.pdbs=SALES
  upg1.target_cdb=CDB23
  upg1.source_dblink.SALES=CLONEPDB 600
  upg1.target_pdb_copy_option.SALES=file_name_convert=none
  upg1.target_version=23
  upg1.start_time=05/11/2023 02:00:00
  

  • I must specify global.keystore to allow AutoUpgrade to create a keystore to work with my encrypted PDB.
  • source_home and target_home list the Oracle Home of the source and target CDB, respectively. It doesn’t matter that the two homes existing on one server only.
  • sid and target_cdb contain the SID of the source and target CDB, respectively.
  • pdbs contains the name of the PDB I want to upgrade, sales. If needed, I could specify more PDBs.
  • source_dblink has the name of the database link (CLONEPDB) and the rate at which the target CDB brings over redo and rolls forward the copy (600 seconds or 10 minutes).
  • I want to use ASM and Oracle Managed Files, so I set target_pdb_copy_option accordingly.
  • Since my source and target CDB are not on the same host, AutoUpgrade can’t automatically determine the target version. I specify that manually using target_version.
  • start_time specifies when downtime starts. At this point, AutoUpgrade refreshes the PDB for the last time and then moves on with the upgrade.

Prepare Source PDB

• I connect to the source PDB. I create a user (for a database link) and grant privileges:

  create user dblinkuser identified by ... ;
  grant create session, 
        create pluggable database, 
        select_catalog_role to dblinkuser;
  grant read on sys.enc$ to dblinkuser;
  

• After the upgrade, I can drop the user again.

Prepare Target CDB

• I connect to the target CDB and create a database link pointing to my source PDB:

  create database link clonepdb
  connect to dblinkuser
  identified by dblinkuser
  using '<connection-string-to-source-pdb>';
  

Analyze and Fix Source PDB

• First, I analyze the source PDB for upgrade readiness. On the source system:

  java -jar autoupgrade.jar -config sales.cfg -mode analyze
  

• The summary report lists the following precheck failures, which I safely ignore:
  • TDE_PASSWORDS_REQUIRED – I will fix that on the target system.
  • TARGET_CDB_AVAILABILITY – the target CDB is remote, and AutoUpgrade can’t analyze it.
• Then, I execute the preupgrade fixups:

  java -jar autoupgrade.jar -config sales.cfg -mode fixups
  

  • This changes my source PDB, so I do it as close to my maintenance window as possible.

Upgrade

• Since my PDB is encrypted, I must add the source and target CDB keystore password to the AutoUpgrade keystore. I start the TDE console on the target host:

  java -jar autoupgrade.jar -config sales.cfg -load_password
  

• In the TDE console, I add the keystore passwords of the source and target CDB:

  TDE> add CDB19
  Enter your secret/Password:    
  Re-enter your secret/Password: 
  TDE> add CDB23
  Enter your secret/Password:    
  Re-enter your secret/Password: 
  

• I save the passwords and convert the AutoUpgrade keystore to an auto-login keystore:

  TDE> save
  Convert the keystore to auto-login [YES|NO] ? 
  

• I start AutoUpgrade in deploy mode:

  java -jar autoupgrade.jar -config sales.cfg -mode deploy
  

  • AutoUpgrade copies the data files over the database link.
  • Rolls the copies of the data files forward with redo from the source.
  • At one point, issues a final refresh and disconnects the PDB from the source.
  • Upgrades the PDB.

• I have now upgraded my PDB to Oracle Database 23c.

The Fine Print

You should:

• Check the words for caution in my previous blog post on AutoUpgrade and refreshable clone PDBs.
• Start a new full backup of the target database after the migration.
• Familiarize yourself with the concept of the AutoUpgrade keystore.

Also, notice:

• The PDB is now on a different Base Database System. You need to update your connection string.
• The source PDB must be Oracle Database 19c or newer to upgrade directly to Oracle Database 23c.
• The OCI console will recognize and display the new PDB after a while. You don’t have to do anything … than to wait for the automatic sync job.