Multiple Homes & Oracle Patch Testing

I am fairly new to Oracle DB's (have done much more MS SQL stuff). The client currently has an Oracle 8.0.5 db on a production server. We're building an 8i system on a new server. Client wants four instances of db running on one server:

• Production instance
• Mirror Production instance (to be used for diagnosing user problems)
• Copy of Production instance for testing vendor patches, upgrades, etc
• Historical instance

This would all be under a single Oracle Home installation. However we also need to test Oracle patches. My reading of the oracle patch docs state they are installed to specific Oracle Homes.

Since we won't test Oracle patches directly on the production Home installation, should we install a second "home" installation on the same server or test the Oracle patches on a completely different server (with a copy of the above production instance installed)? We do have some older surplus servers that could accomodate this.

Any opinions on having multiple oracle home installations on one server and any difficulties in maintaining them?

TIA Glen Moffitt DBA, MCSE Received on Tue Oct 22 2002 - 13:42:22 CDT