NDMP dumpdates file overview

When you set the UPDATE environment variable to Y, the NDMP daemon maintains a dumpdates file to record all but the token-based backup sessions. The timestamp within the dumpdates file helps identify the changed files for the next level-based backup. The entries within the dumpdates file also provide information about the last backup session at a given path and the type of backup session which can be a full, level-based incremental, or snapshot-based backup. This information determines the type of incremental backup you must run subsequently. The entries within the dumpdates file may be obsolete when the backup path is removed. In such a case, all the obsolete entries can be removed from the dumpdates file.