RE: Upgrading GP2013 R2 to GP2016 R2 and SSRS with custom reports
Hello Sandip,
While you'll definitely want to have backups (.rdl files) of your custom SSRS reports, when you re-deploy the SSRS reports from within Dynamics GP, it normally will not overwrite your custom reports unless they are named the same thing as one of our default SSRS reports, which obviously we don't recommend doing.
You'll most likely need the backups of the custom SSRS reports if you upgrade to a newer version of SQL Reporting Services and/or move to a new server for SQL.
If you haven't already done so, this may also be a good question to put on the Microsoft SQL Server - Reporting Services forums, as your questions isn't actually something we would support on the Dynamics GP side, though we luckily have experts such as Mariano and others on these forums that may have additional information to contribute.
Thank you,