4 Backup Strategies and System Availability During an Upgrade

This chapter provides guidelines for planning an upgrade. It consists of the following sections:

Backup Strategies Before Upgrade
Planning for System Downtime

4.1 Backup Strategies Before Upgrade

Before you start the upgrade process, you should have a clear understanding of the backup requirements. These requirements vary somewhat, depending upon whether you are upgrading a middle tier, an OracleAS Metadata Repository, or OracleAS Identity Management.

The following sections provide more information:

Backup Strategies for OracleAS Metadata Repository Upgrades
Backup Strategies for Identity Management Upgrades

4.1.1 Backup Strategies for OracleAS Metadata Repository Upgrades

In most cases, when you upgrade a OracleAS Metadata Repository, you must first upgrade the database that hosts the repository to database version supported by 10g (10.1.4.0.1).

4.1.1.1 Backing Up the Database Before Upgrading the Database Version

As with any database upgrade, standard procedure dictates that you back up your source OracleAS Metadata Repository before you upgrade the database version. For more information, see the Oracle Database documentation for your platform and database version.

4.1.1.2 Backing Up the Database Before Running MRUA

To upgrade the component schemas, you use the Metadata Repository Upgrade Assistant (MRUA). This upgrade of the component schemas is performed "in place," which means that MRUA alters the application server component schemas that exist in the database. It does not create a new copy of the schemas or the data they contain. The changes made by MRUA are irreversible.

As a result, before you run MRUA, you should perform a backup of the database that contains the schemas. This backup will allow you to restore your database to its original state before you run MRUA.

4.1.2 Backup Strategies for Identity Management Upgrades

The OracleAS Identity Management upgrade involves upgrading the configuration and data files in the Oracle home of the OracleAS Identity Management installation, as well as upgrading the OracleAS Identity Management schemas stored in the OracleAS Metadata Repository database.

Consider the following backup strategies when upgrading your OracleAS Identity Management installations:

When you upgrade OracleAS Identity Management, you use the Oracle Universal Installer and the Oracle Application Server 10g (10.1.4.0.1) installation procedure. The installation procedure automatically installs a new 10g (10.1.4.0.1) destination Oracle home and copies configuration data from the source Oracle home to the destination Oracle home.

As a result, the source Oracle home is not modified by the OracleAS Identity Management upgrade process and no additional or new backup strategies are required, other than those you already use to protect your application server data.
The installation procedure also upgrades the OracleAS Identity Management schemas in the OracleAS Metadata Repository. These schemas include the Oracle Internet Directory and OracleAS Single Sign-On schemas.

The upgrade of the OracleAS Identity Management schemas is performed "in place," which means that the procedure alters the OracleAS Identity Management schemas that exist in the database. It does not create a new copy of the schemas or the data they contain. The schemas changes made by the OracleAS Identity Management upgrade are irreversible.

As a result, you should back up the OracleAS Metadata Repository database that contains the OracleAS Identity Management schemas before you upgrade.

4.1.3 Backup Strategies After Upgrading Your Oracle Application Server Instances

After you have completed and verified the upgrade of your Oracle Application Server environment, consider backing up your Oracle Application Server installations so you can easily restore your environment to the newly upgraded state.

In particular, consider backing up the newly upgraded OracleAS Metadata Repository database immediately after the upgrade process. After this initial post-upgrade backup, you can begin your regularly scheduled database backup routine. The initial backup after the upgrade will ensure that you can restore your environment to the newly upgraded state without repeating the upgrade process.

In addition, after you have moved your development or deployment activities to the newly upgraded Oracle Application Server installations, be sure to modify your regular backup routine to include the new Oracle Application Server Oracle homes.

4.2 Planning for System Downtime

This section contains information that will help you answer the following questions as you plan the Oracle Application Server upgrade:

How much downtime should be allocated to upgrade and to troubleshooting the upgrade?
What parts of the system are subject to downtime?
When will the downtime occur?

Refer to the following sections for more information:

Estimated Time Required to Upgrade
Example Execution Times for the Metadata Repository Upgrade Assistant

4.2.1 Estimated Time Required to Upgrade

The duration of upgrade preparation tasks and upgrade processing is of concern when considering downtime. This section provides estimates of the duration of the upgrade of a basic configuration.

For more information, see Table 4-1, "Infrastructure Upgrade Duration Estimates"

Table 4-1 Infrastructure Upgrade Duration Estimates

Operation	Metadata Repository	Identity Management	Colocated Infrastructure^Foot 1
Database backup: The database should be backed up with the user's preferred procedure.	1 hour	Not applicable.	Not applicable
Oracle home backup: The Infrastructure Oracle home should be backed up.	Not applicable.	1 hour	1 hour
Database upgrade: If the Metadata Repository was created with OracleAS RepCA and the database is not a supported version, you must upgrade the database manually to a supported version.	Not applicable	Not applicable	Not applicable
Installation and upgrade with Oracle Universal Installer Depending upon the installation type you are upgrading, the Oracle Universal Installer installs new OracleAS Identity Management components and, if the Oracle home contains an OracleAS Metadata Repository, automatically upgrades the OracleAS Metadata Repository database to the supported version.	3 hours^Foot 2	30 minutes	3 hours, 30 minutes
Database backup before running MRUA	1 hour	Not applicable	1 hour
OracleAS Metadata Repository upgrade with MRUA: Component schemas in the Metadata Repository are upgraded.	1 hour See Section 4.2.2, "Example Execution Times for the Metadata Repository Upgrade Assistant" for more information.	Not applicable	1 hour See Section 4.2.2, "Example Execution Times for the Metadata Repository Upgrade Assistant" for more information.
Identity Management post-upgrade: Perform all post-upgrade tasks.	Not Applicable.	1 hour	1 hours
Total:	6 hours	2 hours, 30 minutes	7 hours, 30 minutes

^Footnote 1The upgrade duration of the Metadata Repository and Identity Management may be shorter than that of the sum of the durations required to upgrade each piece individually, since common tasks need only be executed once.

^Footnote 2Note that if the OracleAS Metadata Repository is being used only to support middle tiers that are part of a database-based Oracle Application Server Farm, the J2EE and Web Cache middle tiers that use the OracleAS Metadata Repository can continue operating during the OracleAS Metadata Repository upgrade.

4.2.2 Example Execution Times for the Metadata Repository Upgrade Assistant

The time required to run MRUA to upgrade the component schemas in the OracleAS Metadata Repository will vary, depending upon your hardware and the amount of data in your OracleAS Metadata Repository. However, testing of MRUA has shown the following typical execution times on the following hardware and software platforms:

1 hour, 40 minutes on a Sun UltraSPARC 60, dual CPU, running Solaris 2.9
45 minutes on a 2.4GHz Pentium 4, running Windows 2000 Service Pack 4