The below command can be used to upgrade SQL server 2008 to SQL server 2008 R2 silently, please enter the correct instance name.
setup.exe /Action=Upgrade /InstanceName=MSSQLSERVER /q /IAcceptSQLServerLicenseTerms
Just a little reproach : i have difficulties to read "correct instance name" deep green and black , it is not easy to read . The part InstanceName=MSSQLSERVER is good.
I hope you will not be vexated by my small remark ( i have poor old eyes )
Thanks a lot for the feedback, corrected.
Thanks, you are quicker than Lucky Luke