Problem
In a client’s environment, over the years, new servers were added to SSRS scale out deployment and old servers decommissioned but not removed.
Solution
Seemed like a very easy fix to launch the Reporting Services Configuration Manager, click on Scale out deployment and select the Server and click on Remove Server.
However this fails, as the servers have been decommissioned and cannot be reached for this operation to be successful.
The other option is to use the rskeymgmt utility to remove the decommissioned servers and keep the scale-out configuration up to date.
Rskeymgmt.exe is located at C:\Program Files (x86)\Microsoft SQL Server\130\Tools\Binn on a 64-bit SQL 2016 instance.
This utility requires .NET Framework 3.5, so that is a prerequisite. The utility will also try to install it if the correct installable path is provided.
After .NET Framework 3.5 is installed, launch the command prompt as administrator.
To list the reporting services instances in a scale out deployment run the following,
rskeymgmt -l
The output will be the format Server\Instance - InstallationID
To remove the SQL instance, run rskeymgmt with -r option. After confirmation, the instance will be removed from the scale out deployment.
rskeymgmt -r <<installation ID>>
Scale out deployment will now show only the active servers
