Upgrading a DB instance for Amazon RDS Custom for Oracle

You can upgrade an Amazon RDS Custom DB instance by modifying it to use a new custom engine version (CEV). For general information about upgrades, see Upgrading a DB instance engine version.

Topics

• Overview of upgrades in RDS Custom for Oracle
• Requirements for RDS Custom for Oracle upgrades
• Considerations for RDS Custom for Oracle database upgrades
• Considerations for RDS Custom for Oracle OS upgrades
• Viewing valid CEV upgrade targets for RDS Custom for Oracle DB instances
• Upgrading an RDS Custom for Oracle DB instance
• Viewing pending database upgrades for RDS Custom DB instances
• Troubleshooting an upgrade failure for an RDS Custom for Oracle DB instance

Overview of upgrades in RDS Custom for Oracle

With RDS Custom for Oracle, you can patch either your Oracle database or your DB instance operating system (OS) by creating new CEVs and then modifying your instance to use the new CEV.

CEV upgrade options

When you create a CEV for an upgrade, you have the following mutually exclusive options:

Database only

Reuse the Amazon Machine Image (AMI) currently in use by your DB instance, but specify different database binaries. RDS Custom allocates a new binary volume and then attaches it to the existing Amazon EC2 instance. RDS Custom replaces the entire database volume with a new volume that uses your target database version.

OS only

Reuse the database binaries currently in use by your DB instance, but specify a different AMI. RDS Custom allocates a new Amazon EC2 instance, and then attaches the existing binary volume to the new instance. The existing database volume is retained.

If you want to upgrade both the OS and database, you must upgrade the CEV twice. You can either upgrade the OS and then the database or upgrade the database and then the OS.

Warning

When you patch your OS, you lose your root volume data and any existing OS customization. Thus, we strongly recommend that you don't use the root volume for installations or for storing permanent data or files. We also recommend that you back up your data before the upgrade.

Patching without CEVs

We strongly recommend that you upgrade your RDS Custom for Oracle DB instance using CEVs. RDS Custom for Oracle automation synchronizes the patch metadata with the database binary on your DB instance.

In special circumstances, RDS Custom supports applying a "one-off" database patch directly to the underlying Amazon EC2 instance directly using the OPatch utility. A valid use case might be a database patch that you want to apply immediately, but the RDS Custom team is upgrading the CEV feature, causing a delay. To apply a database patch manually, perform the following steps:

1. Pause RDS Custom automation.

2. Apply your patch to the database binaries on the Amazon EC2 instance.

3. Resume RDS Custom automation.

A disadvantage of the preceding technique is that you must apply the database patch manually to every instance that you want to upgrade. In contrast, when you create a new CEV, you can create or upgrade multiple DB instances using the same CEV.

General steps for patching your DB instance with a CEV

Whether you patch the OS or your database, perform the following basic steps:

1. Create a CEV that contains either of the following, depending on whether you're patching the database or OS:

   • The Oracle Database RU that you want to apply to your DB instance

   • A different AMI–either the latest available or one that you specify–and an existing CEV to use as a source

   Follow the steps in Creating a CEV.

2. (Optional for database patching) Check available engine version upgrades by running describe-db-engine-versions.

3. Start the patching process by running modify-db-instance.

   The status of the instance being patched differs as follows:

   • While RDS is patching the database, the status of the DB instance changes to Upgrading.

   • While RDS is patching the OS, the status of the DB instance changes to Modifying.

   When the DB instance has the status Available, patching is complete.

4. Confirm that your DB instance uses the new CEV by running describe-db-instances.

Requirements for RDS Custom for Oracle upgrades

When upgrading your RDS Custom for Oracle DB instance to a target CEV, make sure you meet the following requirements:

• The target CEV to which you are upgrading must exist.

• You must upgrade either the OS or the database in a single operation. Upgrading both the OS and the database in a single API call isn't supported.

• The target CEV must use the installation parameter settings that are in the manifest of the current CEV. For example, you can't upgrade a database that uses the default Oracle home to a CEV that uses a nondefault Oracle home.

• For database upgrades, the target CEV must use a new minor database version, not a new major version. For example, you can't upgrade from an Oracle Database 12c CEV to an Oracle Database 19c CEV. But you can upgrade from version 21.0.0.0.ru-2023-04.rur-2023-04.r1 to version 21.0.0.0.ru-2023-07.rur-2023-07.r1.

• For OS upgrades, the target CEV must use a different AMI but have the same major version.