Expiration and purge work together to keep a certain number of restore points available for data recovery and to permanently delete items out of the store that are no longer referenced by the remaining archive restore points, to reclaim storage disk space.
An expiration policy is determined by the end user based on the company's business requirements. Daily, Weekly, Monthly, Quarterly and Yearly retention settings are set in the Store properties on the Expiration tab or on each individual Archive. Restore points that do not meet the retention criteria are moved to the store Recycle Bin and may be restored to the archive prior to running purge. Expired items do not appear in the Restore calendar view for explore and restore. An Expire task is created using the 'Create Store Task' action and normally would be scheduled to run prior to running purge or at some regular interval.
Purge builds an index of all items in the store that are referenced by any archive restore point, and marks those items as keepers. Then, everything else in the store (that is not referenced) is permanently deleted from the store to recover disk space. Purge also rebuilds each plan index, if needed, to remove old entries. Purge will lock down the store while space is being freed so scheduled protection plans that attempt to start while the store is locked will wait in a holding state until the store lock is released. Any running task will be automatically paused and then resume as soon as the store lock is release. A purge task is created using the 'Create Store Task' action and should be scheduled to run at weekly or monthly intervals. Learn more...