OES offers a number of services to automatically back up your network users’ data files.
Salvage and Purge:
By default, all NSS volumes have the Salvage system enabled at the time they are created. With Salvage enabled, deleted files are retained on the volume so that users can restore (salvage) them. File are eventually purged from the system, either manually, or by the system when the Purge Delay setting times out or space is needed on the volume. For more information, see Understanding the NSS Salvage System
in the OES 2018 SP2: NSS File System Administration Guide for Linux.