Bug in the TFS 2008 Uninstall on Standby App Tier

A colleague of mine, who has taken over many of my former TFS duties, ran into an interesting problem today. For reasons I won't get into, we were trying to uninstall TFS 2008 from our Standby App Tier.

The error we ran into was as follows. We found this error in the VSMsiLog which is created for installs and uninstalls.

05/08/08 11:35:14 DDSet_Status: --- STATUS: Found Reports.ReportsService=http://tfs.mycompany.com/ReportServer/ReportService.asmx
05/08/08 11:35:14 DDSet_Status: --- STATUS: Writing VSTF_RS_SERVER=tfs.mycompany.com into C:\Documents and Settings\appwesttfnqasetup\Local Settings\Temp\TfsCurrentConfig.ini section Config
05/08/08 11:35:16 DDSet_Error: *** ERROR: Failed to call WMI on the RS server. The most likely cause is that the firewall is blocking WMI calls or that the RS server is not reachable: The RPC server is unavailable. (Exception from HRESULT: 0x800706BA)
05/08/08 11:35:16 DDSet_Status: Process exited with exit code: 16

05/08/08 11:35:16 DDSet_Error: GetCurrentTfsProperties failed with exit code: 16
MSI (s) (B4!A4) [11:35:22:083]: Product: Microsoft Visual Studio 2008 Team Foundation Server - ENU -- There is a problem with this Windows Installer package. Please refer to the setup log for more information.

You'll notice that the uninstall was looking for the value ReportService which is found in the TfsIntegration database's tbl_service_interface table. The value in that table is a FQDN which we use because we have Primary and Standby App Tiers. As defined in the TFS documentation, only one is active at a time.

The Bug in the uninstall is, if you are setup behind a FQDN the value of ReportService will be the FQDN (e.g. tfs.mycompany.com) instead of the value of the Standby App Tier, which is what you're trying to uninstall.

A quick Google search led me to this blog post by Nick Berardi on his Coder Journal. He ran into a similar issue during an upgrade. He got around the error by changing the ReportService value to match his App Tier.

While I never recommend messing with the TFS databases, being we're in a QA environment I gave Nick's idea a shot. Sure enough, the uninstall finished successfully. I then changed the value back to our FQDN so the Primary App Tier could be functional.

I'm not sure why the uninstall would need these values for Reporting Services. From what the uninstall documentation says, you must uninstall Reporting Services (and Share Point) as an independent step? Anyway, again while I never recommend manually changing values in the TFS databases, we ended up needing to as to get around the uninstall issue.