Reducing Patching Downtimes with Staged Applications Systems
By Steven Chan - EBS-Oracle on Aug 27, 2008
It's axiomatic that everyone wants to minimize maintenance downtimes for their E-Business Suite environments. This is particularly crucial for environments with users in multiple timezones. I've previously summarized some of the most-effective ways of reducing patching downtimes for E-Business Suite environments. As noted in that article, one of the best ways of minimizing your maintenance downtimes is to use a staged Applications system.
The staged approach allows you to perform as many changes as possible in an offline Apps environment, and defers taking down your production environment only for the final database patches tasks. Using this approach, you apply your new patches to an exact clone of your production E-Business Suite environment. This can be done while your production system is still running. The staged Applications environment is then used to run database updates and APPL_TOP changes into your production environment.
Making It Painless
There are a few important things to remember when using a staged Applications system:
- The staged Applications system must be an exact duplicate of your production environment. For example, each physical APPL_TOP of your production system must exist in your staged system.
- Before copying the production Applications system, run the Maintain Current Snapshot task in AD Administration for each APPL_TOP. Having the snapshot of your Production Applications system current will ensure proper patch prerequisite checking when patches are applied.
- Take steps to avoid accidental changes to your production environment, such as ensuring that your staged environment's database has a different ORACLE_SID. You can also change passwords, ports, and other process or service-related parameters to insulate yourself further against a potentially embarrassing errors.
There are a number of other important steps for updating your production database and production APPL_TOP, as well as using the adphmigr.pl utility to synchronize your patch history between your staged and production environments. For full details, see the Metalink Note for your E-Business Suite release:
- Using a Staged Applications System to Reduce Patching Downtime [in Oracle Applications Release 11i] (Metalink Note 242480.1)
- Using a Staged Applications System to Reduce Patching Downtime in Oracle Applications Release 12 (Metalink Note 734025.1)
Commonly confused: "Staged" versus "Shared"
A final reminder about terminology might be helpful. Experienced Apps sysadmins know that we support staged application systems as well as shared application systems. Both of these maintenance strategies have the same goal: they help reduce your patching downtimes. However, it's important to remember that they're not the same thing:
- Staged application systems allow you to do the bulk of your patching in an offline copy of your production environment.
- Shared application systems allow you to patch a single application filesystem that's used by multiple application-tier servers.