I'm in the process of staging an upgrade from ACS 3.2(3) to 4.1(4.13).
The process to complete the upgrade is ACS 3.2(3) -> 3.3(3) -> 4.1(1) -> 4.1.(4.13).
The upgrade steps 3.2(3) -> 3.3(3) and from 3.3(3) to 4.1(1) work reliably, but I am seeing issues when applying 4.1(4.13) in that during the part of the installation when the previous version of CiscoSecure ACS is being removed, errors relating to rad_mon.dll and tac_mon.dll still being in use are generated, following by a number of errors regarding moving components and creating databases. Sometimes the upgrade is successful and sometimes it fails as described above.
Has anyone else encountered this?