Previous Topic: How Media Pools WorkNext Topic: Serial Numbers


Save Sets and Scratch Sets

The set of media containing important data that cannot be overwritten is called the Save Set. You can move media from the Save Set in one media pool to the Save Set in another media pool. Media that has not been formatted for the longest period will be used first.

Note: You will receive a warning if you try to format or erase media in a Save Set.

When the media meets certain criteria in a Save Set (minimum number of media in Save Set and retention period) they are recycled to the Scratch Set. Each time a media in the Scratch Set is written to, it moves from the Scratch Set to the Save Set. Additionally, if Arcserve Backup detects non-blank media in the Scratch Set, the Media Pool Manager controls the usage of the media such that WORM media containing data is not used.

The retention period is the number of days in which a media has not been used before it is moved into the Scratch Set. For example, if you specify a retention period of 14 days, a media remains in the Save Set if it has been used within that specified time. If the media has not been used for 14 days, it is moved to the Scratch Set.

You define the minimum number of media contained within the Save Set. This is the number of media to be retained in the Save Set before the older media are recycled to the Scratch Set. This is a safeguard for preventing data loss in case backups are not done for extended periods of time.

Media pools apply to every media, regardless of which backup type and method were selected. Arcserve Backup performs media pool maintenance at the beginning of a job, and will not allow media in the Save Set to be moved to the Scratch Set until two criteria are met:

If the media meets these criteria, Arcserve Backup prompts for a blank tape or accepts media from the Scratch Set.