During the backup operation a backup directory is created in a designated location for an existing NiFi installation. Backups will capture all critical files (including any internal or external configurations, libraries, scripts and documents) however it excludes backing up repositories and logs due to potential size. If configuration/library files are external from the existing installation folder the backup operation will capture those as well.
During the install operation File Manager will perform installation using the designated NiFi binary file (either tar.gz or zip file) to create a new installation or migrate an existing nifi installation to a new one. Installation can optionally move repositories (if located within the configuration folder of the current installation) to the new installation as well as migrate configuration files to the newer installation.
The restore operation allows an existing installation to revert back to a previous installation. Using an existing backup directory (created from the backup operation) the FileManager utility will restore libraries, scripts and documents as well as revert to previous configurations.
If repositories were changed due to the installation of a newer version of NiFi these may no longer be compatible during restore. In that scenario exclude the -m option to ensure new repositories will be created or, if repositories live outside of the NiFi directory, remove them so they can be recreated on startup after restore.