This procedure is fully documented on Technet, but it spans across two different articles, which might make it a little bit confusing putting together the order of execution. This is the reason I wanted to share the plan I used which resulted in a successful move, including the preservation of custom authored, favorite and scheduled reports.
The steps I followed were directly from the online documentation for moving the SCOM RS role and SSRS instance.
How to Move the Operations Manager Reporting Server in Operations Manager 2007
Moving the Report Server Databases to Another Computer
As always, ensure you have a current backup of any components that will be changed just in case things don’t work out for you. Always test your plans in lab environment before executing in production. If there is any doubt, always refer back to the official documentation links above.
1. Backup the data warehouse.
2. Uninstall the SCOM Report Server role.
3. Restore the data warehouse.
4. On the new SCOM Report Server role, ensure there is a working (default) installation of SSRS. In my case, I had a new installation of Windows 2008 and SSRS 2008.
5. Install the SCOM Report Server role on the new server.
6. Attach the original ReportServer and ReportServerTempDB databases for SSRS (this step is required to preserve any custom reports you have in your original report server deployment).
a. On the original RS server, backup the SSRS encryption key.
b. On the original RS server, stop the Report Server service.
c. If you do not plan to move the SSRS databases, you can skip this step. In SQL Server Management Studio, connect to the SQL instance hosting the original SSRS databases and detach those databases. Move the database files and attach to the new SQL instance. Verify that the RSExecRole is a database role in the report server database and temporary database. RSExecRole must have select, insert, update, delete, and reference permissions on the report server database tables, and execute permissions on the stored procedures.
d. On the new RS server, open Report Services Configuration Tool and connect to the new instance. Select the original SSRS database and click Apply. Restore the encryption keys you had backed up in step 6a.
e. Restart the Report Server service.
7. Verify you can run a report from the Operations Console, and that the management servers are not unhealthy due to report server or data warehouse or report deployment issues. Initially I received errors when I tried to navigate the reporting space. I had to open the Operations Console with the /ClearCache switch and everything worked. All authored, favorite and scheduled reports that were previously created were preserved.
After everything is working, you can optionally delete the ReportServer and ReportServerTempDB databases that were created when you installed the new SSRS instance, since we attached the original databases and are using those.