If you install or copy any reference data file to a directory outside the PowerCenter directory structure, you do not need to back up the directory.
By default, the upgrade operation preserves the contents of the following reference data directories:
<Informatica_installation_directory>/services/DQContent/INFA_Content/dictionaries/
Parent directory for the reference dictionary files.
<Informatica_installation_directory>/services/DQContent/INFA_Content/av/
Parent directory for the address reference data files.
<Informatica_installation_directory>/services/DQContent/INFA_Content/identity/
Parent directory for the identity population data files.
Record the directory location, so that you can restore the directory to the directory structure after you upgrade.