Restoring the earlier version of the Presentation Server if the upgrade fails
When you upgrade the TrueSight Presentation Server to 11.0, the installer automatically backs up the installation and configuration files of the Presentation Server 10.7 and 10.5 installation in one of the following folders:
In a high availability deployment, if the upgrade is successful on the Primary server and fails on the Secondary server or the reverse, you must restore the earlier version of both Primary and Secondary servers.